47 results on '"Xiaojuan Lai"'
Search Results
2. Polymerization Behavior and Rheological Properties of a Surfactant-Modified Reactive Hydrophobic Monomer
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Xin Wen, Lei Wang, Xiaojuan Lai, Guiru Liu, Wenwen Yang, Jinhao Gao, Yameng Liu, and Wenyu Cui
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wormlike micelles ,free-radical polymerization ,synergistic effect ,hydrophobic association ,thixotropy ,viscoelasticity ,Chemistry ,QD1-999 - Abstract
The structures and properties of hydrophobic association polymers can be controlled using micelles. In this work, we synthesize a reactive hydrophobic surfactant monomer, KS-3, from oleic acid, N,N-dimethylpropylenediamine, and allyl chloride. A strong synergistic effect between KS-3 and cocamidopropyl betaine in aqueous solution enhances the hydrophilic dispersibility of KS-3, thereby transforming spherical micelles into cylindrical micelles. KS-3 was grafted onto a polyacrylamide chain via aqueous free-radical polymerization to obtain RES, a hydrophobic association polymer. Structural analysis revealed that the RES polymers assembled in wormlike micelles were more tightly arranged than those assembled in spherical micelles, resulting in a compact network structure in water, smooth surface, and high thermal stability. Rheological tests revealed that the synthesized polymers with wormlike and spherical micelles exhibited shear-thinning properties along with different structural strengths and viscoelasticities. Therefore, controlling the micellar state can effectively regulate the polymer properties. The polymers obtained through wormlike micelle polymerization have potential applications in fields with high demands, such as drug release, water purification, and oilfield development.
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- 2023
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3. Two-Level Self-Thickening Mechanism of a Novel Acid Thickener with a Hydrophobic-Associated Structure during High-Temperature Acidification Processes
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Peng Li, Lei Wang, Xiaojuan Lai, Jinhao Gao, Zhiqiang Dang, Rong Wang, Fan Mao, Yemin Li, and Guangliang Jia
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hydrophobic association ,high-temperature resistance ,acid self-thickening ,thickening acid ,cationic polyacrylamide ,Organic chemistry ,QD241-441 - Abstract
Two acid thickeners, ADMC and ADOM, were prepared by aqueous solution polymerization using acrylamide (AM) and methacryloyloxyethyl trimethyl ammonium chloride (DMC) as raw materials, with or without the introduction of octadecyl polyoxyethylene ether methacrylate (OEMA). It was characterized by FTIR, 1H NMR, and the fluorescence spectra of pyrene. The double-layer thickening mechanism of ADOM was proved by comparing the thickening and rheological properties of ADMC and ADOM tested by a six-speed rotary viscometer and a HAKKE MARSIV rheometer during the acidification process. The results showed that the synthetic product was the target product; the first stage of the self-thickening ADOM fresh acid solution during high-temperature acidification was mainly affected by Ca2+ concentration, and the second stage of self-thickening was mainly affected by temperature. The residual viscosity of the 0.8 wt% ADOM residual acid solution was 250, 201.5, and 61.3 mPa·s, respectively, after shearing at 90, 120, and 150 °C for 60 min at a shear rate of 170 s−1. The thickening acid ADOM with a hydrophobic association structure has good temperature resistance and shear resistance, which can be used for high-temperature deep-well acid fracturing. In addition, no metal crosslinking agent was introduced in the system to avoid damage to its formation, and ADOM exhibited good resistance to Ca2+, which could provide ideas for the reinjection of the acidizing flowback fluid. It also has certain advantages for environmental protection.
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- 2024
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4. Preparation of supramolecular viscoelastic polymers with shear, temperature, and salt resistance/sensitivity by amphiphilic functional monomer modification
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Meiling Fan, Lei Wang, Jing Li, Ping He, Xiaojuan Lai, Jinhao Gao, Guiru Liu, and Xin Wen
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Supramolecular polymers ,Amphiphilic functional monomer ,Linear entanglement ,Rheology ,Hydraulic fracturing ,Polymers and polymer manufacture ,TP1080-1185 - Abstract
To develop high-salinity, high-temperature reservoirs, a novel supramolecular viscoelastic polymer-based fracturing fluid modified with an amphiphilic functional monomer was developed. Investigation of the thickening ability, solubility, and rheology revealed that the as-developed gel system with a rigid hydrophobically associating space network structure and linear entanglement can improve the thickening ability, solubility, temperature adaptation range, and chemical environment resistance sensitivity of supramolecular polymers. The surface/interfacial tension test revealed that the modified polymers exhibit surface and interface activity. At an MHAP-15 concentration of 1500 mg/L, the surface tension was 39.29 Nm/m. At an MHAP-15 concentration of 800 mg/L, a minimum interfacial tension of 0.86 Nm/m was observed. The shear sensitivity test revealed that the copolymer fluid exhibits a high creep recovery performance and elastic response as well as a 100% viscosity recovery rate. In addition, the viscoelasticity and thixotropy of the copolymer solution were investigated. The results revealed that the higher the number of the oxyethylene groups in amphiphilic functional monomers, the higher the increase in the viscous modulus of the copolymer solution. In the modified polymer, the highest energy was required for the destruction of the MHAP-15 solution, reaching 66.5 Pa; this result confirmed the best synergistic effect of hydrophobic association and linear entanglement of the MHAP-15 solution molecules, as well as the best temperature and salt resistance. The viscosity of 0.6 wt% MHAP-15 was 120 mPa s after shearing for 50 min at 120 °C and at 170 s−1. At 160 °C and 100 s−1, the viscosity of the 0.8 wt% MHAP-15 polymer solution reached 153 mPa s after shearing for 50 min. At a NaCl concentration of 25 × 104 mg/L, the viscosities of the 0.6 wt% and 0.8 wt% MHAP-15 solutions were 203 and 245 mPa s, respectively, indicative of the stimulation response of salt thickening. At a CaCl2 concentration of 2 × 104 mg/L, the viscosity of 0.6 wt% MHAP-15 was 87 mPa s, and the viscosity retention rate was 47.9%. Finally, by X-ray diffraction, the particle size test in solution, and scanning electron microscopy, the higher the number of oxyethylene groups in the amphiphilic functional monomers, the higher the mixing entropy of copolymers, and the particle size in solution and multi-peak distribution were higher, as well as more clear linear entanglement between copolymers; all of these factors were conducive to the formation of large-scale supramolecular structures of super-bridged copolymers.
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- 2022
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5. Preparation And Characterization Of Waterborne Polyurethane-acrylate Modified By Functionalized Graphene Oxide
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Xiaojuan Lai, Xiaohu Liu, Lei Wang, Bin Yuan, Guiru Liu, and Hui Cao
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waterborne polyurethane polyacrylate ,graphene oxide ,silane coupling agent ,in situ polymerization ,composite emulsion ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Chemical engineering ,TP155-156 ,Physics ,QC1-999 - Abstract
A water-borne polyurethane-acrylate emulsion (WPUA) prepolymer was synthesized by using polycaprolactone diol (PCL), toluene diisocyanate (TDI), 2,2-bis (hydroxymethyl) butyric acid (DMBA), 1,4-butanediol (BDO) and methyl methacrylate (MMA) as main materials. After the coupling modified nano-SiO2 was grafted with graphene oxide, it was polymerized with polyurethane prepolymer in situ. The amine-free waterborne polyurethane-acrylate composite emulsion (SiO2-NH2-GO/WPUA) modified by functionalized graphene was prepared by self-emulsification. The amount of functionalized graphene was discussed, and its composite emulsion and film were tested and characterized. Compared with waterborne polyurethane-acrylate (WPUA), SiO2-NH2-GO/WPUA has better temperature resistance and film properties. When the mass fraction of SiO2-NH2-GO is 0.75%, compared with unmodified emulsion film, the thermal decomposition temperature of the composite film increased by 14.51oC; The tensile strength increased to 81.28 MPa; the adhesive prepared by the composite emulsion has a T-peel strength of 15.4 N in aluminum foil/PVC film. The indexes such as the easy oxide meet the standard of pharmaceutical packaging containers, indicating that the waterborne polyurethane adhesive is suitable for pharmaceutical packaging.
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- 2022
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6. Evaluation of Tolerability, Pharmacokinetics and Pharmacodynamics of Vicagrel, a Novel P2Y12 Antagonist, in Healthy Chinese Volunteers
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Xiaojiao Li, Cai Liu, Xiaoxue Zhu, Haijing Wei, Hong Zhang, Hong Chen, Guiling Chen, Deming Yang, Hongbin Sun, Zhenwei Shen, Yifan Zhang, Wei Li, Jin Yang, Yongqiang Liu, Xiaojuan Lai, Yanchun Gong, Xuefang Liu, Yongguo Li, Dafang Zhong, Junqi Niu, Bin Liu, and Yanhua Ding
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vicagrel ,pharmacokinetics ,pharmacodynamics ,safety ,clopidogrel ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Background: Vicagrel is a novel anti-platelet drug and hydrolyzed to the same intermediate as clopidogrel via esterase, instead of CYP2C19. Here we report the first clinical trial on the tolerability, pharmacokinetics and pharmacodynamics of different doses of vicagrel, and comparison with clopidogrel in healthy Chinese volunteers.Methods: This study was conducted in two parts. Study I was a dose-escalating (5–15 mg) study. For each dose, 15 participants were randomized into three groups (total n = 45); nine participants were given vicagrel, three were given clopidogrel, and three were given a placebo. Study II was conducted to assess interactions between vicagrel and aspirin in 15 healthy participants. The plasma concentrations of the metabolites of vicagrel and clopidogrel were determined using a LC-MS/MS method. Platelet aggregation was assessed using the VerifyNow-P2Y12 assay.Results: Vicagrel (5–15 mg per day) dosing for 10 days or addition of aspirin was well tolerated in healthy volunteers. The exposure of the active metabolite increased proportionally across the dose range and was higher (~10-fold) than clopidogrel. The levels of IPA dosing 75 mg clopidogrel were between the responses of 5 mg and 10 mg vicagrel. After a single loading dose of vicagrel (30 mg) and a once-daily maintenance dose (7.5 mg) for 8 days, the maximum inhibition of platelet aggregation was similar to that seen with the combined use of vicagrel and aspirin (100 mg/day).Conclusion: Oral vicagrel demonstrated a favorable safety profile and excellent anti-platelet activity, which could be a promising P2Y12 antagonist as anti-platelet drug and can be further developed in phase II/III studies, and marketing for the unmet medical needs of cardiovascular diseases. The study was registered at http://www.chictr.org.cn (ChiCTR-IIR-16009260).
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- 2018
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7. Advancing gene feature selection: Comprehensive learning modified hunger games search for high-dimensional data.
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Yueyue Huang, Minmin Wu, Ding Li, Zhiqiang Chen, Xueshu Yu, Yifan Gao, Xiaojuan Lai, Lianmin Ye, Shichao Quan, Yingru Lu, Ali Asghar Heidari, Huiling Chen 0001, and Jingye Pan
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- 2024
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8. Preparation and viscoelasticity of a novel hydrophobic associating polymer with salt stimulation responsiveness by functional monomer modification for fracturing fuids
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Xiaojuan Lai, Guiru Liu, Yong Liu, Xinping Dong, Xiaoqing Liu, Yasir Mukhtar, Lei Wang, Xin Wen, and Lijuan Lu
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In this study, a salt-resistant hydrophobic association polymer (PZDY) is synthesized by acrylamide, octadecyl dimethylallyl ammonium chloride and decane polyoxyethylene ether acrylate by aqueous polymerization. The infrared spectroscopy, fluorescence spectroscopy, scanning electron microscopy and other characterization methods were used to study its properties, and the rheological properties of PZDY solution is analyzed. The results showed that when concentration of NaCl is less than 5 wt% and CaCl2 is less than 1 wt%, the viscosity of 0.4 wt% PZDY increases with the increase of salt concentration. When the salt concentration continued to increase, the PZDY viscosity gradually decreased. Investigation of the rheological behavior showed that 0.6 wt% PZDY in 5 wt% NaCl and 1 wt% CaCl2 solution, could withstand a temperature up to 180 °C, after being sheared for 2500 s at 170 s−1, and its viscosity was greater than 50 mPa·s. Moreover, the viscosity of 0.6 wt% PZDY in 5 wt% NaCl increased from 104 to 205 mPa·s and the viscosity of 0.6 wt% PZDY in 1 wt% CaCl2 increased from 110 to 157 mPa·s, when at a shear rate of 170 s-1, at 180 ° C and the shear time was less than 500 s. Meanwhile, SEM results showed that salt addition enhanced the quasi-spatial network structure, with closer clustering of PZDY molecules in NaCl solution than in CaCl2 solution. The storage modulus (G′) and loss modulus (G") increased with the increase of PZDY concentration. Therefore, PZDY can be used to improve the heat and shear resistance of fracturing fluids and enhance oil recovery.
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- 2023
9. Antiplatelet effect, safety, and pharmacokinetics of vicagrel in patients with coronary artery disease undergoing percutaneous coronary intervention
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Xin Zhao, Sicong Ma, Yi Kang, Chengchun Tang, Bin Liu, Hong Jiang, Mingqi Zheng, Yu Tang, Hongbin Sun, Yongqiang Liu, Xiaojuan Lai, Yanchun Gong, Yongguo Li, Zizhao Qi, Ling Ren, Jing Li, Yi Li, and Yaling Han
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Cytochrome P-450 CYP2C19 ,Percutaneous Coronary Intervention ,Humans ,Hemorrhage ,Pharmacology (medical) ,Coronary Artery Disease ,cardiovascular diseases ,Cardiology and Cardiovascular Medicine ,Platelet Aggregation Inhibitors ,Clopidogrel - Abstract
Aims Vicagrel, a novel antiplatelet prodrug to overcome the residual high platelet reactivity of clopidogrel induced by inactive metabolism and cytochrome P450 (CYP) 2C19 polymorphisms, provides favourable antiplatelet inhibition in healthy volunteers. However, its antiplatelet effect and safety in patients with coronary artery disease (CAD) are unclear. Methods and results This was a multicentre, randomized, double-blind, triple-dummy, dose-exploring phase II trial comparing the antiplatelet activity and safety of vicagrel at different doses vs. those of clopidogrel in patients with CAD undergoing percutaneous coronary intervention (PCI). The primary endpoint was inhibition of adenosine diphosphate (ADP)-induced platelet aggregation (%IPA) after loading and maintenance doses (LD/MD) at 28 days. Safety endpoints included adverse events (AEs) and Bleeding Academic Research Consortium-defined any bleeding. Pharmacokinetic (PK) profiles and the influence of CYP2C19 polymorphisms were explored in subgroup analysis. Two hundred and seventy-nine patients diagnosed with stable CAD (51.97%), unstable angina (40.86%), and myocardial infarction (7.17%) were randomized to receive vicagrel 20/5 mg (LD/MD), 24/6 mg, or 30/7.5 mg or clopidogrel 300/75 mg in combination with aspirin. %IPAs on Day 28 were 30.19%, 35.02%, 45.61%, and 32.55% for vicagrel 20/5, 24/6, and 30/7.5 mg and clopidogrel, respectively, and were comparable across all groups (P = 0.0694). The plasma concentration of the vicagrel active metabolite M15-2 had a similar area under curve and Tmax to those of clopidogrel. There were no significant differences in AEs (4.35%, 0%, 1.45%, and 5.56% for vicagrel 20/5, 24/6, and 30/7.5 mg and clopidogrel, P = 0.6667) or any bleeding (13.04%, 14.06%, 11.59%, and 11.11% for vicagrel 20/5, 24/6, and 30/7.5 mg and clopidogrel, respectively, P = 0.95) across four groups. %IPAs and PK profiles of vicagrel did not vary significantly among different CYP2C19 metabolizers. Conclusion Vicagrel had comparable antiplatelet effect and safety to clopidogrel in patients with CAD undergoing PCI.
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- 2022
10. Reactive carbamate surfactants: Synthesis, characterization, and improved rheological properties of hydrophobically modified polyacrylamide containing surfactant structures
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Guiru Liu, Xiaojuan Lai, Xu Cheng, Yutian Lei, Lei Wang, Xin Wen, Meiling Fan, Jinhao Gao, Yong Liu, and Qinqin Ma
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Polymers and Plastics ,Materials Chemistry ,General Chemistry ,Surfaces, Coatings and Films - Published
- 2022
11. Preparation and properties of a clean, low‐damage waterproof locking damage multifunctional integrated water‐based fracturing fluid
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Meiling Fan, Xiaojuan Lai, Meirong Tang, Jing Li, Lei Wang, and Jinhao Gao
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Polymers and Plastics ,Materials Chemistry ,General Chemistry ,Surfaces, Coatings and Films - Published
- 2022
12. Rheological properties and ultra-high salt resistance of novel hydrophobically associating copolymers for fracturing fluids
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Meiling Fan, Xiaojuan Lai, Jing Li, Tingting Wang, Lei Wang, Jinhao Gao, Xin Wen, Guiru Liu, and Yong Liu
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Polymers and Plastics ,Materials Chemistry ,General Chemistry ,Condensed Matter Physics - Published
- 2022
13. Facile fabrication and characterization of high-performance Borax-PVA hydrogel
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Xiaowu Yang, Zhang Kang, Lidong Liang, Xiaojuan Lai, Tao Wang, Xing Zhang, Pengfei Hu, Liewei Qiu, Jianguang Bai, Chen Wang, and Shen Zhifeng
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Materials science ,Borax ,technology, industry, and agriculture ,macromolecular substances ,General Chemistry ,Dynamic mechanical analysis ,Condensed Matter Physics ,Microstructure ,complex mixtures ,Polyvinyl alcohol ,Electronic, Optical and Magnetic Materials ,Biomaterials ,chemistry.chemical_compound ,Compressive strength ,chemistry ,Chemical engineering ,Ultimate tensile strength ,Self-healing hydrogels ,Materials Chemistry ,Ceramics and Composites ,medicine ,Swelling ,medicine.symptom - Abstract
Borax-PVA hydrogels with excellent mechanical properties are prepared by simple physical mixing of polyvinyl alcohol (PVA, thickener) and borax (cross-linking agent) at room temperature. The resulting hydrogel is a three-dimensional structure composed of boric ester bonds as physical crosslinking points. Thus, the spatial structure, swelling properties, viscoelastic properties, tensile properties, and self-healing properties of hydrogels with different ratios of borax and PVA are studied. XRD confirmed that the hydrogels have similar structures near 2θ values of 10 and 20. The microstructure of the hydrogel is confirmed by SEM and TEM. With an increase of borax mass fraction, the pore structure and morphology of hydrogel are more ordered, with substantial quantities of water immobilized within their three-dimensional structure. The viscoelastic properties and tensile properties showed that when the mass fraction of borax is 5%, the storage modulus and compressive stress of the hydrogel are the highest, reaching 100 Pa and 5.6 kPa, respectively. In addition, through physical and chemical stimulation (heating and varying pH, respectively), the hydrogels also showed reversible gel–sol conversion characteristics, indicating that the boric ester bonds have self-healing properties.
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- 2021
14. Preparation and Properties of a New Type of Hydrophobically Associating Quaternary Copolymer Hpaf for Fracturing Fluid
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Yosri Abdalhalim Sheikh Tawil, Xiaojuan Lai, Lei Wang, and Yasir Mukhtar
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History ,Polymers and Plastics ,Business and International Management ,Industrial and Manufacturing Engineering - Published
- 2022
15. Properties of a novel imbibition polymer with ultra-high wetting ability as a fracturing fluid system
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Lei Wang, Xiaojuan Lai, Guanghua Zhang, Xianwen Li, Li Ding, Chuanqing Huang, Jinhao Gao, and Xiaojia Xue
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chemistry.chemical_classification ,02 engineering and technology ,General Chemistry ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Microstructure ,01 natural sciences ,Catalysis ,0104 chemical sciences ,Surface tension ,Contact angle ,chemistry ,Rheology ,Materials Chemistry ,Zeta potential ,Imbibition ,Wetting ,Composite material ,0210 nano-technology - Abstract
A novel fracturing fluid system with wettability was prepared. XRD and TGA of the polymer were measured. Rheology and SEM experiments showed that the fracturing fluid had a dense network structure. The microstructures of the gel breaking fluid were obtained using SEM and TEM tests, which demonstrated more obvious crosslinking. Contact angle and wetting function of the gel breaking fluid were evaluated on sandstone. The NFW fracturing fluid showed excellent rheological properties at 90 °C. The surface tension of the gel breaking fluid was relatively low, being 20 mN m−1. The WA, BET data and zeta potential of the NFW gel breaking fluid suggested that the material was absorbed on the sandstone surface and a bilayer was formed. Meanwhile, CT and AFM studies indicated that the imbibition effect of the gel breaking fluid could obviously be observed on the sandstone. The contact angle increased to 146° when the sandstone was immersed in solution, which suggested that the wettability of the rock was changed. The imbibition efficiency of NFW is higher than that of water. Thus, this fracturing fluid with wettability could be an alternative for development in tight oil reservoirs.
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- 2020
16. Semi-mechanistic population pharmacokinetics analysis reveals distinct CYP2C19 dependency in the bioactivation of vicagrel and clopidogrel to active metabolite M15–2
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Lin, Zhang, Hongbin, Sun, Yongqiang, Liu, Xiaojuan, Lai, Yanchun, Gong, Xuefang, Liu, Yong-Guo, Li, Yang, He, Eric Y, Zhang, and Xiaoyu, Yan
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Cytochrome P-450 CYP2C19 ,Ticlopidine ,Humans ,Pharmaceutical Science ,Galanin ,Thiophenes ,Substance P ,Platelet Aggregation Inhibitors ,Clopidogrel ,Phenylacetates - Abstract
Vicagrel is a novel antiplatelet drug used to mitigate clopidogrel resistance due to CYP2C19 polymorphism. This study aimed to develop a semi-mechanistic population pharmacokinetic (PopPK) model to characterize the pharmacokinetic (PK) profile of M15-2, the active metabolite of vicagrel and clopidogrel, and to evaluate the influence of CYP2C19 polymorphisms and other covariates in healthy subjects and patients with acute coronary syndrome (ACS) after oral administration.The analysis utilized data from 213 subjects, including 178 healthy subjects and 35 patients, from five clinical trials. PopPK modeling and simulation were used to estimate PopPK parameters and evaluate the impact of covariates.The M15-2 PK profiles were well characterized by a model incorporating transit compartments, two-compartment parent models and two-compartment M15-2 models for both vicagrel and clopidogrel. The parameter estimates indicated the dose fraction of vicagrel that formed M15-2 was approximately 20-fold that of clopidogrel. Covariate analysis identified a significant effect of CYP2C19 on M15-2 apparent clearance (CL/F) and apparent volume of distribution (V3/F) for clopidogrel but only CL/F for vicagrel. The analysis suggested that the nonlinear PK of M15-2 for clopidogrel was due the first-step bioactivation of clopidogrel to 2-oxoclopidogrel.The model illustrated the bioactivation of vicagrel is more efficient and less dependent on CYP2C19 than that of clopidogrel. M15-2 is formed in a linear process from vicagrel, versus a nonlinear and less predictable process from clopidogrel. Advantages in both PK and pharmacogenetics suggest that vicagrel may reduce the complexity of currently recommended CYP2C19-based dosage adjustment for clopidogrel.
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- 2022
17. Effect of Spacer on Surface Activity and Foam Properties of Betaine Gemini Surfactants
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Liu Pei, Wang Jie, Huaixin Li, Lei Wang, and Xiaojuan Lai
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chemistry.chemical_compound ,Betaine ,chemistry ,General Chemical Engineering ,Sodium ,Polymer chemistry ,chemistry.chemical_element ,General Chemistry ,Methylene ,Condensed Matter Physics - Abstract
A series of betaine-type Gemini surfactants (Cs-BGS, where C is the methylene part of the spacer, s = 2, 4, 6) were synthesized from sodium 3-chloro-2-hydroxypropanesulfonate, oleamidopropyl dimethylamine and bromoalkane. The chemical structure of the prepared compounds was confirmed by 1H NMR, 13C NMR, IR spectra, and elemental analysis. Their critical micelle formation concentrations (CMC) in the aqueous solution at 25 °C were determined by measuring the surface tension and the electrical conductivity. As the length of the spacer increased, the values of their CMC and γcmc also increased. The surface tension measurements of C2-BGS revealed that the surfactant possesses a low CMC, is very efficient in reducing the surface tension, and is very strongly adsorbed at the air-water interface. In addition, the adsorption and micellization behavior of Cs-BGS was estimated from the efficiency of surface tension reduction (pC20), minimum average surface area per surfactant molecule (Amin), and standard free energies of micellization and adsorption. These properties are significantly affected by the spacers and the adsorption is more favored than the micellization.
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- 2019
18. Pharmacokinetics and pharmacokinetic/pharmacodynamic relationship of vicagrel, a novel thienopyridine P2Y12 inhibitor, compared with clopidogrel in healthy Chinese subjects following single oral dosing
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Wei Li, Cai Liu, Jin Yang, Youming Lu, Yifan Zhang, Liu Xuefang, Liu Yongqiang, Xue-Ning Li, Yanchun Gong, Hongbin Sun, Dafang Zhong, Yongguo Li, Wei-Li Chen, Xiaoyan Chen, and Xiaojuan Lai
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Thienopyridine ,business.industry ,Metabolite ,Cmax ,Pharmaceutical Science ,02 engineering and technology ,Pharmacology ,021001 nanoscience & nanotechnology ,Clopidogrel ,030226 pharmacology & pharmacy ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,P2Y12 ,Pharmacokinetics ,chemistry ,Oral administration ,Medicine ,0210 nano-technology ,business ,Active metabolite ,medicine.drug - Abstract
Background and objectives Vicagrel, a novel thienopyridine antiplatelet agent, is an analogue of clopidogrel in development for the treatment of acute coronary syndromes. This study investigated the pharmacokinetic properties of vicagrel after single oral dosing with a direct comparison with clopidogrel in healthy Chinese subjects in the first two phase I clinical studies. The relationship between the exposure to the active metabolite and the platelet reactivity was also assessed for vicagrel. Methods Study A was a single-ascending-dose study of vicagrel (5–75 mg) compared with clopidogrel (75 mg) in 67 healthy volunteers. Study B was a randomized, two-period, crossover, loading-dose study of vicagrel 20 mg compared with clopidogrel 300 mg in 12 healthy subjects. Plasma concentrations of three common metabolites of vicagrel and clopidogrel, the active thiol metabolite H4, the inactive thiol metabolite H3, and the S-methylated form of H3 (SM3, the major metabolite of vicagrel), were determined using a validated UHPLC–MS/MS method. The relationship between the AUC0−t of active H4 and the P2Y12 reaction units at 4 h after administration of vicagrel was investigated. Blood concentrations of vicagrel were determined after a single oral administration of vicagrel 25 mg to two healthy Chinese subjects. Results In the single-ascending-dose study, vicagrel was metabolized rapidly with the median tmax for the three metabolites, namely, H4, H3, and SM3, ranging from 0.25–1.75 h. The pharmacokinetics of the three metabolites for vicagrel were linear across the dose range of 5–75 mg, with the mean Cmax and AUCs for H4 and H3 increasing in an approximately 1:1 dose-proportional manner and for SM3 increasing in a Conclusions Vicagrel was rapidly and extensively metabolized, and the levels of the parent drug in circulation were very low. The pharmacokinetics of the three metabolites of vicagrel were linear and predictable across the dose range of 5–75 mg. The AUC of active H4 was apparently associated with the P2Y12 reaction units for vicagrel. For active H4, vicagrel 5 mg produced similar exposure (AUC) with more rapid appearance compared with clopidogrel 75 mg, and vicagrel 20 mg produced even slightly higher exposure (AUC) with more rapid appearance compared with clopidogrel 300 mg in humans. Trial Registration: CTR20150346, CTR20160379.
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- 2019
19. Rheological properties of an ultra-high salt hydrophobic associated polymer as a fracturing fluid system
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Huaqiang Shi, Chuanqing Huang, Lei Wang, Jinhao Gao, Guanghua Zhang, Xiaojuan Lai, Xin Wen, Li Ding, and Shaoyun Ma
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chemistry.chemical_classification ,Scanning electron microscope ,General Chemical Engineering ,02 engineering and technology ,General Chemistry ,Polymer ,Dynamic mechanical analysis ,Apparent viscosity ,Sulfonic acid ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Polymerization ,Chemical engineering ,Rheology ,0210 nano-technology ,Acrylic acid - Abstract
Herein, a novel ultra-high salt hydrophobic associated polymer, UUCPAM, was prepared using acrylamide, acrylic acid, 2-acrylamide-2-methyl propane sulfonic acid and the hydrophobic monomer UUC. Polymerization exothermic test results indicated that the increase in the hydrophobic monomer content led to an increase in the exothermic time, which is considerably conducive to the formation of hydrophobic structures. The scanning electron microscopy and transmission electron microscopy studies showed that the polymer had complex network structures and that this phenomenon was considerably obvious in NaCl solution. The fluorescence probe experiment verified that the critical association concentration of this polymer decreased with an increase in the hydrophobic monomer. Rheology studies indicated that the polymer had good temperature and shear resistance in NaCl solution. Moreover, the apparent viscosity of the polymer remained above 80 mPa s when 0.3 wt% UUCPAM was added at 170 s−1 in 20 000 mg L−1 NaCl solution at 90 °C. The storage modulus that indicated strong elasticity increased with an increase in the polymer concentration. Meanwhile, the number of hydrophobic micro-zones increased, thus forming dense network structures. Therefore, the polymer was found to have excellent salt resistance and extensive application prospects.
- Published
- 2019
20. Synthesis and characterizations of waterborne polyurethane modified with 3-aminopropyltriethoxysilane
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Xiaojuan, Lai, Xiaorui, Li, Lei, Wang, and Yiding, Shen
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- 2010
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21. Impacts of CYP2C19 genetic polymorphisms on bioavailability and effect on platelet adhesion of vicagrel, a novel thienopyridine P2Y(12) inhibitor
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Xiaoxue Zhu, Yu Xia, Yongguo Li, Xiaojuan Lai, Haijing Wei, Yifan Zhang, Xiaojiao Li, Yanhua Ding, Liu Xuefang, Hongbin Sun, Dafang Zhong, Yan Zhan, Cai Liu, Y. L. Zhu, Yanchun Gong, Liu Yongqiang, and Hong Zhang
- Subjects
Male ,Ticlopidine ,Thienopyridine ,Platelet Aggregation ,Biological Availability ,CYP2C19 ,Thiophenes ,Pharmacology ,Loading dose ,P2Y12 ,Pharmacokinetics ,medicine ,Humans ,Pharmacology (medical) ,cardiovascular diseases ,Active metabolite ,Phenylacetates ,Cross-Over Studies ,Polymorphism, Genetic ,business.industry ,Original Articles ,Clopidogrel ,Cytochrome P-450 CYP2C19 ,Pharmacodynamics ,Female ,business ,Platelet Aggregation Inhibitors ,medicine.drug ,circulatory and respiratory physiology - Abstract
AIMS: We investigated the impacts of CYP2C19 polymorphisms on pharmacokinetics and pharmacodynamics of vicagrel in healthy Chinese subjects. METHODS: CYP2C19 extensive metabolizers (EMs), intermediate metabolizers (IMs) and poor metabolizers (PMs; 16 subjects/group) participated in a randomized, open‐label, 2‐period cross‐over study. Each study period lasted 7 days, with a loading dose of 24 mg of vicagrel or 300 mg of clopidogrel on day 1, and maintenance doses of 6 mg of vicagrel or 75 mg of clopidogrel daily from day 2 to day 7. The pharmacokinetics and pharmacodynamics were assessed on day 1 and day 7. RESULTS: After a loading dose, the AUC(0‐t) of the active metabolite H4 by vicagrel was slightly lower in IMs and PMs (decreased by 21 and 27%, respectively) compared to EMs. Similar results were found after maintenance doses. In EMs, the AUC(0‐t) of H4 by vicagrel was somewhat higher than clopidogrel after the loading dose, and comparable with clopidogrel (90% confidence interval 0.94, 1.21) after the maintenance doses. However, it was much higher than clopidogrel in PMs, with a 1.28‐fold (loading dose) and a 73% (maintenance doses) increases compared to clopidogrel (P < 0.001). Consequently, the inhibition of platelet aggregation by vicagrel was greater than clopidogrel after both loading dose (28.2 vs 12.4% at 4 hours, P < 0.01) and maintenance doses (42.8 vs 24.6% at 4 hours, P < 0.001) in PMs. CONCLUSIONS: CYP2C19 polymorphisms have less impact on vicagrel as compared to clopidogrel. Drug exposure and response to vicagrel in PMs were even higher than to clopidogrel in IMs.
- Published
- 2020
22. Platelet inhibitory activity, tolerability, and safety of vicagrel, a novel thienopyridine P2Y12 inhibitor
- Author
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Jin Yang, Yongguo Li, Xue-Ning Li, Hanjing Chen, Fei Yuan, Mengjie Yang, Wei-Li Chen, Liu Xuefang, Hongbin Sun, Liu Yongqiang, Hong-Rong Xu, Hui Li, Yanchun Gong, Xiaojuan Lai, Chao Liu, and Lei Sheng
- Subjects
Adult ,Male ,Thienopyridine ,Platelet Aggregation ,Platelet Function Tests ,Observational Study ,Thiophenes ,Pharmacology ,Placebo ,vicagrel ,healthy Chinese subjects ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,P2Y12 ,Double-Blind Method ,pharmacodynamics ,Potency ,Medicine ,Humans ,Platelet ,030212 general & internal medicine ,Phenylacetates ,Dose-Response Relationship, Drug ,business.industry ,General Medicine ,Clopidogrel ,Platelet Activation ,Tolerability ,030220 oncology & carcinogenesis ,Pharmacodynamics ,Female ,business ,Platelet Aggregation Inhibitors ,medicine.drug ,Research Article - Abstract
Vicagrel is a new antiplatelet pro-drug based on clopidogrel sulfur lactone metabolites. The purpose of the study was to evaluate the safety, tolerability, and pharmacodynamics (PD) of vicagrel in healthy Chinese subjects. This study was designed as a single-center, randomized, double-blind, placebo-controlled, single oral ascending dose study. Fifty nine subjects were assigned to 6 vicagrel dose cohorts (5, 10, 20, 40, 60, and 75 mg), and 8 subjects were assigned to 75 mg clopidogrel. Within each vicagrel dose cohort, the 10 subjects (9 in the 75 mg cohort) were randomized 4:1 to receive vicagrel or placebo. Platelet function was assessed using VerifyNowTM P2Y12. ΔP2Y12 reaction units (ΔPRU) and percent inhibition platelet aggregation (%IPA) were used to evaluate the PD of vicagrel. Although the number of adverse events (AEs) increased with vicagrel dose, none were considered serious, suggesting that vicagrel is safe and well-tolerated. The ΔPRU and %IPA patterns suggest that inhibition of ADP-induced platelet aggregation increased in a dose-dependent manner across the 10 to 40 mg dose range. The inhibitory effect was nearly complete at 4 hours (mean %IPA 87.9%–93.0%, mean ΔPRU 206.6–240.0) for doses of 40 to 75 mg of vicagrel. In contrast, for 5 mg vicagrel and 75 mg clopidogrel, there were no measurable effects on platelet aggregation throughout the study. The results suggest that vicagrel at 40 to 75 mg inhibits ADP-induced platelet aggregation, with a fast onset of action and significantly greater potency than clopidogrel. These findings indicate that vicagrel may be a highly effective and well-tolerated antiplatelet agent.
- Published
- 2020
23. Synthesis of a Gemini Betaine Surfactant and Its Properties as Foam Drainage Agent
- Author
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Qunzheng Zhang, Hui Qi, Zhong-Gang Bai, and Xiaojuan Lai
- Subjects
Oleamide ,General Chemical Engineering ,Sodium ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Surface tension ,chemistry.chemical_compound ,Betaine ,020401 chemical engineering ,chemistry ,Pulmonary surfactant ,Foam drainage ,Critical micelle concentration ,0204 chemical engineering ,Fourier transform infrared spectroscopy ,0210 nano-technology ,Nuclear chemistry - Abstract
A novel betaine Gemini surfactant (B18-4-18) was synthesized by two-step reaction with N,N-dimethyl oleoaminde-propylamine, sodium 2-hydroxy-3-chloro propanesulfate and 1,4-dibromobutane as main raw materials. The structure of the synthesized betaine Gemini surfactant was characterized by Fourier transform infrared spectroscopy (FTIR) and 1H nuclear magnetic resonance spectrum (1HNMR), the surface tension curve and related parameters were obtained by surface tension measurements. The surface tension of oleamide hydroxypropyl betaine (B18) and the Gemini surfactant (B18-4-18) at different concentrations was measured. The experimental results showed that the structure of the synthesized compounds was in conformity with the expected structure of the surfactants. The critical micelle concentration of B18 was 6.1 × 10−6 mol/L, the corresponding surface tension was 34.27 mN/m. The critical micelle concentration of B18-4-18 was 5.0 × 10−6 mol/L, the corresponding surface tension was 31.67 mN/m at 25°C. The liquid carrying rate of B18 and B18-4-18 can reach 87% and 92% in water respectively. The liquid carrying rate of B18 and B18-4-18 can reach 82% and 84% in 150 000 mg/L mineralized water. The liquid carrying rate of B18 and B18-4-18 can reach 64% and 67% respectively at 10% condensate oil.
- Published
- 2018
24. Development and validation of a sensitive and rapid UHPLC–MS/MS method for the simultaneous quantification of the common active and inactive metabolites of vicagrel and clopidogrel in human plasma
- Author
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Liu Yongqiang, Dafang Zhong, Yanchun Gong, Xiaojuan Lai, Youming Lu, Jin Yang, Cai Liu, Yifan Zhang, Xiaoyan Chen, Yongguo Li, Liu Xuefang, and Hongbin Sun
- Subjects
China ,Spectrometry, Mass, Electrospray Ionization ,Ticlopidine ,Time Factors ,Thienopyridine ,Metabolite ,Clinical Biochemistry ,Administration, Oral ,Pharmaceutical Science ,Thiophenes ,030226 pharmacology & pharmacy ,01 natural sciences ,High-performance liquid chromatography ,Analytical Chemistry ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Drug Stability ,Isomerism ,Tandem Mass Spectrometry ,Drug Discovery ,Humans ,Protein precipitation ,Prodrugs ,Acute Coronary Syndrome ,Chromatography, High Pressure Liquid ,Spectroscopy ,Active metabolite ,Phenylacetates ,Chromatography ,010401 analytical chemistry ,Selected reaction monitoring ,Reproducibility of Results ,Prodrug ,Deuterium ,Healthy Volunteers ,Clopidogrel ,0104 chemical sciences ,chemistry ,Calibration ,Platelet aggregation inhibitor ,Platelet Aggregation Inhibitors - Abstract
Vicagrel, an analog of clopidogrel, is a novel thienopyridine P2Y12 antagonist in clinical development in China for the treatment of acute coronary syndromes. Vicagrel and clopidogrel are prodrugs requiring metabolic activation to produce a pharmacologically active thiol metabolite (H4) in vivo. The formation of H4 from vicagrel in humans is promising more efficient and consistent than that from clopidogrel. After oral dosing of vicagrel or clopidogrel to humans, the active thiol metabolite H4 and two inactive metabolites closely related to H4 formation (the thiol metabolite H3 and the S-methylated metabolite SM3) were observed in plasma; SM3 was the most abundant drug-related component of vicagrel in circulation. In this study, a sensitive, rapid, and reliable UHPLC-MS/MS method was developed for the simultaneous determination of derivatized H3 (MP-H3), derivatized H4 (MP-H4), and SM3 in human plasma to investigate the pharmacokinetics of vicagrel in healthy subjects compared with clopidogrel. After extracted from 50μL of plasma by simple protein precipitation, the analytes and stable isotope-labeled internal standards were separated on an Acquity UPLC BEH C18 column (100mm×2.1mm, 1.7μm). The mobile phase was acetonitrile-water-formic acid (45:55:0.0275, v/v/v) delivered at a flow rate of 0.45mL/min under isocratic elution. The total chromatographic run time was 6min. MP-H3, MP-H4, and SM3 were separated from their corresponding isomers under the chromatographic conditions. Mass spectrometric detection was conducted in multiple reaction monitoring mode on an AB Sciex Qtrap 5500 System using a positive electrospray ionization interface. The calibration curves were linear in the following ranges: 0.100-200ng/mL for MP-H3 and MP-H4 and 1.00-1000ng/mL for SM3. The intra- and inter-day accuracy and precision for each analyte at all concentrations were within acceptable limits (±15%). The validated method was successfully applied to compare the pharmacokinetics of vicagrel and clopidogrel after a single oral administration to healthy subjects in the first-in-human study of vicagrel.
- Published
- 2018
25. Evaluation of Tolerability, Pharmacokinetics and Pharmacodynamics of Vicagrel, a Novel P2Y12 Antagonist, in Healthy Chinese Volunteers
- Author
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Hong Chen, Yanchun Gong, Yanhua Ding, Dafang Zhong, Deming Yang, Jin Yang, Bin Liu, Yifan Zhang, Xiaojuan Lai, Hong Zhang, Liu Yongqiang, Wei Li, Cai Liu, Guiling Chen, Liu Xuefang, Hongbin Sun, Xiaoxue Zhu, Xiaojiao Li, Junqi Niu, Yongguo Li, Zhenwei Shen, and Haijing Wei
- Subjects
safety ,CYP2C19 ,030204 cardiovascular system & hematology ,Pharmacology ,030226 pharmacology & pharmacy ,Loading dose ,vicagrel ,03 medical and health sciences ,0302 clinical medicine ,Pharmacokinetics ,medicine ,pharmacodynamics ,Pharmacology (medical) ,Aspirin ,clopidogrel ,Maintenance dose ,business.industry ,lcsh:RM1-950 ,Clopidogrel ,Clinical Trial ,lcsh:Therapeutics. Pharmacology ,Tolerability ,Pharmacodynamics ,business ,pharmacokinetics ,medicine.drug - Abstract
Background: Vicagrel is a novel anti-platelet drug and hydrolyzed to the same intermediate as clopidogrel via esterase, instead of CYP2C19. Here we report the first clinical trial on the tolerability, pharmacokinetics and pharmacodynamics of different doses of vicagrel, and comparison with clopidogrel in healthy Chinese volunteers. Methods: This study was conducted in two parts. Study I was a dose-escalating (5–15 mg) study. For each dose, 15 participants were randomized into three groups (total n = 45); nine participants were given vicagrel, three were given clopidogrel, and three were given a placebo. Study II was conducted to assess interactions between vicagrel and aspirin in 15 healthy participants. The plasma concentrations of the metabolites of vicagrel and clopidogrel were determined using a LC-MS/MS method. Platelet aggregation was assessed using the VerifyNow-P2Y12 assay. Results: Vicagrel (5–15 mg per day) dosing for 10 days or addition of aspirin was well tolerated in healthy volunteers. The exposure of the active metabolite increased proportionally across the dose range and was higher (~10-fold) than clopidogrel. The levels of IPA dosing 75 mg clopidogrel were between the responses of 5 mg and 10 mg vicagrel. After a single loading dose of vicagrel (30 mg) and a once-daily maintenance dose (7.5 mg) for 8 days, the maximum inhibition of platelet aggregation was similar to that seen with the combined use of vicagrel and aspirin (100 mg/day). Conclusion: Oral vicagrel demonstrated a favorable safety profile and excellent anti-platelet activity, which could be a promising P2Y12 antagonist as anti-platelet drug and can be further developed in phase II/III studies, and marketing for the unmet medical needs of cardiovascular diseases. The study was registered at http://www.chictr.org.cn (ChiCTR-IIR-16009260).
- Published
- 2018
26. Pharmacokinetics and pharmacokinetic/pharmacodynamic relationship of vicagrel, a novel thienopyridine P2Y
- Author
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Cai, Liu, Yifan, Zhang, Weili, Chen, Youming, Lu, Wei, Li, Yongqiang, Liu, Xiaojuan, Lai, Yanchun, Gong, Xuefang, Liu, Yongguo, Li, Xiaoyan, Chen, Xuening, Li, Hongbin, Sun, Jin, Yang, and Dafang, Zhong
- Subjects
Adult ,Cross-Over Studies ,Adolescent ,Platelet Aggregation ,Thiophenes ,Healthy Volunteers ,Clopidogrel ,Young Adult ,Asian People ,Double-Blind Method ,Purinergic P2Y Receptor Antagonists ,Humans ,Platelet Aggregation Inhibitors ,Phenylacetates - Abstract
Vicagrel, a novel thienopyridine antiplatelet agent, is an analogue of clopidogrel in development for the treatment of acute coronary syndromes. This study investigated the pharmacokinetic properties of vicagrel after single oral dosing with a direct comparison with clopidogrel in healthy Chinese subjects in the first two phase I clinical studies. The relationship between the exposure to the active metabolite and the platelet reactivity was also assessed for vicagrel.Study A was a single-ascending-dose study of vicagrel (5-75 mg) compared with clopidogrel (75 mg) in 67 healthy volunteers. Study B was a randomized, two-period, crossover, loading-dose study of vicagrel 20 mg compared with clopidogrel 300 mg in 12 healthy subjects. Plasma concentrations of three common metabolites of vicagrel and clopidogrel, the active thiol metabolite H4, the inactive thiol metabolite H3, and the S-methylated form of H3 (SM3, the major metabolite of vicagrel), were determined using a validated UHPLC-MS/MS method. The relationship between the AUCIn the single-ascending-dose study, vicagrel was metabolized rapidly with the median tVicagrel was rapidly and extensively metabolized, and the levels of the parent drug in circulation were very low. The pharmacokinetics of the three metabolites of vicagrel were linear and predictable across the dose range of 5-75 mg. The AUC of active H4 was apparently associated with the P2YCTR20150346, CTR20160379.
- Published
- 2018
27. Erratum to: Study on properties of hydrophobic associating polymer as drag reduction agent for fracturing fluid
- Author
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Lei Wang, Wang Dan, Xing Guo, Yiding Shen, and Xiaojuan Lai
- Subjects
chemistry.chemical_classification ,Fracturing fluid ,Materials science ,Polymers and Plastics ,chemistry ,Reducing agent ,Drag ,Organic Chemistry ,Materials Chemistry ,Polymer ,Composite material - Published
- 2017
28. Micromorphology and mechanism of polyurethane/polyacrylate membranes modified with epoxide group
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Xiaojuan Lai, Xiaorong Wang, and Yiding Shen
- Subjects
Thermogravimetric analysis ,Glycidyl methacrylate ,Acrylate ,Materials science ,General Chemical Engineering ,Organic Chemistry ,Surfaces, Coatings and Films ,chemistry.chemical_compound ,Membrane ,Differential scanning calorimetry ,Dynamic light scattering ,chemistry ,Chemical engineering ,Polymer chemistry ,Materials Chemistry ,Thermal stability ,Polyurethane - Abstract
Polyurethane/polyacrylate (PUA) composite emulsions were synthesized based on the presence of preformed polyurethane chains. Glycidyl methacrylate (GMA), an acrylate monomer, was introduced into the system. Surface tension measurements assured the surface activities of the polyurethane emulsion. Dynamic light scattering (DLS) result showed that the average diameters and polydispersity were increased with the increment of GMA content. X-ray photoelectron spectroscopy (XPS) result indicated that the upper surface was rich in PU phase. The peak deconvolution results of XPS also confirmed the formation of PUA. The crosslinking degree and tensile strength were both enhanced due to the reaction between the carboxyl groups and the epoxide groups. Thermo gravimetric analysis (TGA) of the membranes showed that the thermal stability enhanced and the decomposition temperature was much higher than the pure PU membrane. X-ray diffraction (XRD) analysis, together with differential scanning calorimetry (DSC) results, demonstrated the amorphous nature of the PU matrix. Atomic force microscopy (AFM) observation performed the extremely flat membrane.
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- 2014
29. Study on properties of hydrophobic associating polymer as drag reduction agent for fracturing fluid
- Author
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Lei Wang, Xing Guo, Yiding Shen, Wang Dan, and Xiaojuan Lai
- Subjects
chemistry.chemical_classification ,Materials science ,Aqueous solution ,Polymers and Plastics ,Rheometer ,Organic Chemistry ,Solution polymerization ,02 engineering and technology ,Polymer ,Dynamic mechanical analysis ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Shear rate ,chemistry.chemical_compound ,Viscosity ,Monomer ,chemistry ,Materials Chemistry ,Composite material ,0210 nano-technology - Abstract
In the paper, the hydrophobic associating polymer ACS-210 was prepared by solution polymerization of acrylamide, acrylic acid, salt-resisting monomer and hydrophobic monomer. Chemical structure and properties of the polymer was characterized by FTIR, TGA and XRD. The rheological property of ACS-210 solution was investigated by rheometer. The frictional resistance of the ACS-210 solutions at different application condition was examined using friction testing system. Results showed that the thermal stability of polymer ACS-210 increases and crystallinity of ACS-210 declines after incorporating of hydrophobic monomer. The viscosity of ACS-210 solution of different concentration decreased with prolonging the shearing time and the retention rate of viscosity is relatively high after long shearing time. The relation curve between the viscosity of polymer solution and shear rate followed the power law model. When the concentration of ACS-210 aqueous solution was less than the critical associating concentrations, storage modulus G’ is less than loss modulus G”, the association was weaker between the molecular chains, and the effective spatial structure did not form. After increasing the concentration of the polymer solution, G’ is more than G”, the degree of association of polymer is stronger. The synthesized polymer has favorable drag reduction effect. The molecular weight is not the only factor to determine drag reduction efficiency. The hydrophobic association can also improve the drag reduction efficiency.
- Published
- 2016
30. Preparation and properties of a novel waterborne fluorinated polyurethane–acrylate hybrid emulsion
- Author
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Yuhua Niu, Biao Du, Chen Wang, Peizhi Li, Xiaorui Li, and Xiaojuan Lai
- Subjects
Acrylate ,Materials science ,Polymers and Plastics ,Radical polymerization ,Surface tension ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,Monomer ,Chemical engineering ,chemistry ,Emulsion ,Polymer chemistry ,Materials Chemistry ,Zeta potential ,Shore durometer ,Physical and Theoretical Chemistry ,Glass transition - Abstract
The waterborne fluorinated polyurethane–acrylate hybrid emulsion (WFPUA) was prepared by two steps, including the preparation of the fluorinated alcohol blocked polyurethanes (FBPU) in the mixtures of vinyl monomers and fluorinated monomers and then the free radical polymerization after the pre-emulsification of the said system. The effects of hydrophilic monomer (MDEA) on the surfactivity and the emulsifiability of the FBPU were firstly reported. Then, the particle size (d), zeta potential (ζ), and viscosity (η) of the WFPUA hybrid emulsion were characterized, respectively. At the same time, the surface properties and the mechanical properties of the films were investigated. The results show that the increase of MDEA is good for the emulsifiability and the lower surface tension of the FBPU. This increase improves the stability, the ζ and η, yet decreases the d of the WFPUA emulsion. However, it has disadvantages to the hydrophobic performance of the WFPUA films. When the content of the MDEA in the WFPUA is increased from 4.67 to 14.89 %, the surface free energies are increased from 22.22 to 27.28 mJ m−2 and the attenuation rate of the contact angle–time curve is increased from 0.3051° to 0.6290°/min. Also, with the increase of MDEA, the tensile strength and the shore hardness of the film are increased, but its elongation at break is decreased. The storage moduli of the film are enhanced remarkably. Meanwhile, the glass transition temperature of the soft segment [Tg(s)] is reduced and that of the hard segment [Tg(h)] is raised.
- Published
- 2013
31. Platelet inhibitory activity, tolerability, and safety of vicagrel, a novel thienopyridine P2Y12 inhibitor.
- Author
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Hui Li, Hanjing Chen, Weili Chen, Hongrong Xu, Fei Yuan, Mengjie Yang, Hongbin Sun, Jin Yang, Yongqiang Liu, Xiaojuan Lai, Yanchun Gong, Xuefang Liu, Yongguo Li, Lei Sheng, Chao Liu, Xuening Li, Li, Hui, Chen, Hanjing, Chen, Weili, and Xu, Hongrong
- Published
- 2020
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32. Synthesis and Mechanical Properties of Membranes Prepared from Hydroxyl-Terminated Polyurethane Alcohol Dispersion Modified by Epoxy Resin
- Author
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Chuangzhao Xu, Xiaorong Wang, Zhiwen Li, Xiaojuan Lai, and Yiding Shen
- Subjects
Materials science ,Polymers and Plastics ,General Chemical Engineering ,Materials Science (miscellaneous) ,Infrared spectroscopy ,Epoxy ,chemistry.chemical_compound ,Membrane ,chemistry ,visual_art ,Attenuated total reflection ,Ultimate tensile strength ,Materials Chemistry ,visual_art.visual_art_medium ,Copolymer ,Thermal stability ,Composite material ,Polyurethane - Abstract
Hydroxyl-terminated polyurethane (EPPU) modified by epoxy resin was synthesized. The structure of polyurethane (PU) was characterized by Attenuated total reflection Fourier transform infrared spectrometer (ATR-FTIR) and transmission electron microscope (TEM). The effect of w(E-44) on thermal stability and mechanical properties of the membranes were also measured. ATR-FTIR and TEM indicates that epoxy resin has been successfully incorporated into the copolymer's main chain, and the thermal stability has improved. It was found that greater mechanical properties of PU were obtained when chemical networks were formed between PU and epoxy resin. The maximum tensile strength is up to 6.99 MPa.
- Published
- 2012
33. Preparation and properties of self-crosslinkable polyurethane/silane hybrid emulsion
- Author
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Yiding Shen, Lei Wang, and Xiaojuan Lai
- Subjects
Thermogravimetric analysis ,Materials science ,Polymers and Plastics ,Organic Chemistry ,Propanamide ,Silane ,chemistry.chemical_compound ,chemistry ,Polymer chemistry ,Emulsion ,Materials Chemistry ,Thermal stability ,Isophorone diisocyanate ,Curing (chemistry) ,Polyurethane - Abstract
Self-crosslinkable polyurethane emulsion containing active carbonyl group was obtained using dihydroxyketon N-[(1,1-dimethyl-2-acetyl)ethyl]-β-dihydroxyethylamino propanamide(DDP) and 1,4-butanediol as chain extenders, isophorone diisocyanate (IPDI), polyether polyol (PTMG1000), dimethylol propionic acid (DMPA) and trimethylol propane (TMP) as main materials, γ-aminopropyltriethoxysilane (APTES) as end capping agent. Then adipic dihydrazide was added into the emulsion. The structure and composition of DDP and the films were confirmed by means of FTIR and 1H nuclear magnetic resonance (1H-NMR) spectrometer, the test results indicated that the reaction between ketone carbonyl and hydrazine has happened during the film curing. The effects of n(NH2NH-)/n(C=O) and DDP content on the properties of the films were studied. The results show that water absorption of the films decreases from 39.3% to 18.9%, crosslinking degree increases from 51.5% to 90.2%, tensile strength increases from 20.1 MPa to 28.3 MPa and pencil hardness is 2H when the DDP content increases from 0% to 6.13%. TGA analysis indicates that the Ketone-Hydrazide crosslinking structure can improve thermal stability of the films.
- Published
- 2011
34. Preparation and Performance of Waterborne Polyurethane/Nanosilica Hybrid Materials
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Lei Wang, Xiaojuan Lai, Zhongjin Li, and Yiding Shen
- Subjects
Materials science ,Absorption of water ,Polymers and Plastics ,General Chemical Engineering ,Materials Science (miscellaneous) ,chemistry.chemical_compound ,chemistry ,Emulsion ,Ultimate tensile strength ,Materials Chemistry ,Particle size ,Fourier transform infrared spectroscopy ,Composite material ,Hybrid material ,Prepolymer ,Polyurethane - Abstract
The polyurethane prepolymer was synthesized, and hydrophilic nano-sized silica (A200) was added to the prepolymer with KH550 as a coupling agent, then a waterborne polyurethane/nanosilica hybrid material (WPUNS) was obtained by a sol-gel process. The structure and performance of the WPUNS films were studied by FTIR, TG, DSC and physical mechanical testing. The particle size and distribution of WPUNS hybrid emulsion was analyzed by a dynamic light scatter (DLS). The morphology of emulsion and films were observed by Transmission Electron Microscope (TEM) and Atomic Force Microscope (AFM), respectively. FTIR analysis indicates the formation of chemical bond between WPU and A200. TEM images display that A200 particles were encapsulated by PU macromolecules and formed a composite particles structure. As the mass fraction of A200 increased from 0 to 2%, the particle size increased from 79.9 nm to 139.9 nm, the tensile strength of the films increased from 6.32 MPa to 20.46 MPa, water absorption decreased from 28...
- Published
- 2011
35. Effect of nanosilica content on properties of polyurethane/silica hybrid emulsion and its films
- Author
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Lei Wang, Yiding Shen, Xiaojuan Lai, and Zhongjin Li
- Subjects
Absorption of water ,Materials science ,Polymers and Plastics ,General Chemistry ,Surfaces, Coatings and Films ,Thermogravimetry ,chemistry.chemical_compound ,Differential scanning calorimetry ,Chemical engineering ,chemistry ,Emulsion ,Materials Chemistry ,Thermal stability ,Fourier transform infrared spectroscopy ,Composite material ,Glass transition ,Polyurethane - Abstract
Polyurethane/silica hybrid emulsion (PUSi) was synthesized by the reaction of isophorone isocyanate, polyether polyol, hydrophilic nanosilica (A200), dimethylol propionic acid, trimethylol propane, and 3-aminopropyltriethoxysilane (KH550). The films of the waterborne polyurethane (WPU) were prepared. The structure of the polyurethane was characterized by Fourier transform infrared spectrometer (FTIR), thermogravimetry (TG), and differential scanning calorimetry (DSC). The particle size distribution and morphology of emulsion were examined. Influence of nanosilica content on the mechanical properties and solvent absorption of the cast films were also measured quantificationally. FTIR indicates that NH2 of KH550 reacted with NCO of polyurethane. TG analysis indicates that nanosilica can improve thermal stability of polyurethane. There is no clear effect of nanosilica on the glass transition of soft segments. It was found that greater mechanical properties of WPU were obtained when chemical networks were formed by sol-gel process. As the nanosilica content increases, water absorption and ethanol absorption decreased. The particle size increases with increase of A200 content. PUSi hybrid emulsions are endowed with pseudoplasticity. The apparent viscosity of emulsions increased and then decreased with addition of A200. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
- Published
- 2010
36. FILM-FORMING MECHANISM AND PROPERTIES OF KETONE HYDRAZINE CROSSLINKED AND SILANE COUPLED WATERBORNE POLYURETHANE
- Author
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Xiaojuan Lai, Yiding Shen, and Jing Zhao
- Subjects
chemistry.chemical_classification ,chemistry.chemical_compound ,Materials science ,Ketone ,Polymers and Plastics ,chemistry ,General Chemical Engineering ,Polymer chemistry ,Hydrazine ,General Chemistry ,Silane ,Polyurethane - Published
- 2010
37. Synthesis and properties of crosslinked waterborne polyurethane
- Author
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Zhongjin Li, Yiding Shen, Lei Wang, Xiaojuan Lai, and Min Liu
- Subjects
Absorption of water ,Materials science ,Polymers and Plastics ,Organic Chemistry ,Isocyanate ,Crystallinity ,chemistry.chemical_compound ,Differential scanning calorimetry ,chemistry ,Ultimate tensile strength ,Polymer chemistry ,Materials Chemistry ,Fourier transform infrared spectroscopy ,Prepolymer ,Polyurethane ,Nuclear chemistry - Abstract
Waterborne polyurethane prepolymer was prepared by the reaction of isophorone isocyanate(IPDI), polyether polyol(PTMG), dimethylol propionic acid(DMPA) and trimethylol propane(TMP), which was modified by silicane coupling agent(APTES) to form highly crosslinked polyurethane emulsion. The films of the waterborne polyurethane were prepared. The structure of the polyurethane was characterized by Fourier transform infared spectrometer (FTIR), X-ray diffraction (XRD) and differential scanning calorimeter (DSC). The mechanical properties and water absorption of the films were measured. FT-IR indicates that APTES reacted with -NCO of polyurethane. XRD and DSC shows that crystallinity of polyurethane decreased with the increase of w(APTES). Tensile strength increases as the NCO/OH ratio increases. Tensile strength of films increases with increase of w(DMPA) and elongation at break decreases. The water absorption decreases with the increase of w(TMP) when w(TMP) is lower than 1.8%. As the mass fraction of APTES increases from 0% to 10%, the tensile strength of PU films increased from 18 MPa to 28 MPa, water absorption and ethanol absorption decreased.
- Published
- 2010
38. SYNTHESIS AND PROPERTIES OF WATERBORNE POLYURETHANES MODIFIED BY EPOXY RESIN
- Author
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Xiaojuan Lai, Xiaorui Li, and Lei Wang
- Subjects
Materials science ,Polymers and Plastics ,General Chemical Engineering ,visual_art ,visual_art.visual_art_medium ,General Chemistry ,Epoxy ,Composite material - Published
- 2009
39. Synthesis, characterization, and adsorption capacity of crosslinked starch microspheres withN,N′-methylene bisacrylamide
- Author
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Lei Wang, Xiaojuan Lai, Xin-Fa Zhao, and Zhongjin Li
- Subjects
Thermogravimetric analysis ,Langmuir ,Polymers and Plastics ,Chemistry ,Starch ,technology, industry, and agriculture ,General Chemistry ,Surfaces, Coatings and Films ,Crystallinity ,chemistry.chemical_compound ,Adsorption ,Differential scanning calorimetry ,Chemical engineering ,Polymer chemistry ,Materials Chemistry ,Thermal stability ,Fourier transform infrared spectroscopy - Abstract
Crosslinked starch microspheres (CSMs) were prepared in an inverse suspension system. Scanning electron microscopy observation indicated that the CSMs were uniform in granularity with a smooth spherical particulate surface. The particle size analysis revealed that the average diameter was 18.2 μm and that 85.8% of the microspheres were of a diameter below 30 μm. The structural characteristics of the carbonyl group and the second acrylamide by Fourier transform infrared spectroscopy of the CSMs showed that the soluble starch obviously crosslinked with N,N′-methylene bisacrylamide. The physical properties of the CSMs were analyzed by way of X-ray diffraction, differential scanning calorimetry, and thermogravimetric analysis. The results show that the crosslinking resulted in an increase in thermal stability and a decrease in crystallinity of the CSMs compared with soluble starch. The adsorption capacity of the CSMs increased with increasing concentration of methylene blue. The lower temperature was in favor of the adsorption capacity of the CSMs. The adsorption mode of methylene blue by the CSMs agreed more with the Langmuir isothermal equation. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
- Published
- 2008
40. Effect of Spacer on Surface Activity and Foam Properties of Betaine Gemini Surfactants.
- Author
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Lei Wang, Pei Liu, Xiaojuan Lai, Jie Wang, and Huaixin Li
- Published
- 2019
- Full Text
- View/download PDF
41. Micromorphology and thermal properties of polyurethane/polyacrylate soap-free emulsion in the presence of functional monomers
- Author
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Yiding Shen, Xiaorong Wang, Xiaojuan Lai, Du Yuan, and Guanjun Liu
- Subjects
chemistry.chemical_classification ,Acrylate ,Materials science ,Polymers and Plastics ,Butyl acrylate ,Organic Chemistry ,Emulsion polymerization ,Polymer ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,Dynamic light scattering ,Emulsion ,Polymer chemistry ,Materials Chemistry ,Thermal stability ,Fourier transform infrared spectroscopy - Abstract
Novel polyurethane/polyacrylate (PUA) composite emulsions were synthesized by soap-free emulsion polymerization method from methyl methacrylate (MMA), butyl acrylate (BA), and 2-Hydroxyethyl acrylate (HEA) in the presence of PU as seeds and a polymerizable emulsifier-Allyloxy hvdroxyl propanesulfonic salt (AHPS). Effects of the AHPS content on the properties of the emulsions and films were studied. Dynamic light scattering (DLS) result showed that the average diameters and polydispersity were decreased with the increment of AHPS content. Fourier transform infrared spectroscopy (FT-IR) result shows that AHPS was introduced into the PUAS chains. Their thermal stability and Tg of the films increased gradually with augment of AHPS amount in polymer. X-ray photoelectron spectroscopy (XPS) analysis showed that sodium was preferably enriched on the surface of latex particles. Atomic force microscopy (AFM) observation performed the extremely flat membrane.
- Published
- 2014
42. Synthesis and characterization of self-crosslinked polyurethane/polyacrylate composite emulsion based on carbonyl–hydrazide reaction
- Author
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Xiaorui Li, Xiaojuan Lai, Yiding Shen, Xiaorong Wang, Wang Rui, Fan Huabo, and Haiyan Lv
- Subjects
Materials science ,Absorption of water ,Aqueous solution ,Polymers and Plastics ,Organic Chemistry ,Composite number ,Hydrazine ,Hydrazide ,chemistry.chemical_compound ,chemistry ,Polymer chemistry ,Emulsion ,Materials Chemistry ,Fourier transform infrared spectroscopy ,Polyurethane - Abstract
Self-crosslinkable aqueous polyurethane (PU)/polyacrylate (PA) composite emulsion was obtained by radical copolymerization. Fourier transform infrared spectroscopy (FT-IR) result shows that the cross-linking reaction between the carbonyl group and the hydrazine group has happened. The influence of the hydrazide-carbonyl molar ratio and the PA content on the properties of the composite emulsions and their films were investigated. The results show that, under the optimal hydrazide-carbonyl molar ratio (n (hydrazine group)/n (carbonyl group) =1:1), the water absorption is 10.56 %, and the mechanical properties and thermal stabilities are both improved. As the PA content increases from 0 wt% to 15 wt%, the tensile strength increases from 5.7 MPa to 7.3 MPa and the gel content increases from 70.3 % to 87 %.
- Published
- 2013
43. Preparation and application of cationic blocked waterborne polyurethane as paper strength agent
- Author
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Min Liu, Yuanbo Song, and Xiaojuan Lai
- Subjects
Materials science ,Polymers and Plastics ,Tertiary amine ,Organic Chemistry ,Cationic polymerization ,Propanamide ,chemistry.chemical_compound ,chemistry ,Wet strength ,Ultimate tensile strength ,Polycaprolactone ,Polymer chemistry ,Materials Chemistry ,Isophorone diisocyanate ,Nuclear chemistry ,Polyurethane - Abstract
Cationic blocked waterborne polyurethane (CBWPU) as paper strength agent was prepared by the reaction of N-[(1,1-dimethyl-2-acetyl)ethyl]-β-dihydroxyethylamino propanamide(DDP), isophorone diisocyanate(IPDI), polycaprolactone glycol(PCL) and bisphenol A, with imidazole as blocking agent and N-methyldiethanolamine as hydrophilic chain-extending agent. Effects of the blocked ratio and the dosage of CBWPU on the physical properties of the treated paper were studied. The chemical structure of CBWPU and the surface morphology of the paper surface are characterized by Fourier transform infared spectrometer(FT-IR) spectra and scanning electron microscopy(SEM). The results show that the paper strength, especially the wet tensile index and the wet strength of paper can be obviously improved with the increasing of the blocked ratio and the dosage of CBWPU. FT-IR result shows that structures of tertiary amine group, imidazole ring and urethane group are found in CBWPU molecular structure. SEM obsevation of the treated paper reveals that the exiestence of a lot of filamentous materials and films, which can improve the crosslinking between fibers.
- Published
- 2013
44. Rheological property of the regenerable polyhydroxy alcohol fracturing fluid system
- Author
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Fan Huabo, Lei Wang, and Xiaojuan Lai
- Subjects
Temperature resistance ,Vinyl alcohol ,Materials science ,Polymers and Plastics ,Organic Chemistry ,chemistry.chemical_element ,Alcohol ,Viscoelasticity ,Fracturing fluid ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,Rheology ,Materials Chemistry ,Boron - Abstract
According to the characteristic of polyhydroxy alcohol fracturing fluid system, the regeneration of the system was investigated for the first time. A stable organic boron crosslinking poly(vinyl alcohol) regenerable polyhydroxy alcohol fracturing fluid system was prepared, and the rheological property of the polyhydroxy alcohol fracturing fluid system with different regenerable times was researched. The effect of regenerable times on the rheological property of the system was studied. The results showed that the aims of gel breaking and regeneration can be achieved by regulating its pH value and controlling its crosslinking degree. With the increment of the regenerable times, both the temperature resistance and shearing resistance performances were decreased, and the viscoelasticity of the gel was also reduced.
- Published
- 2013
45. Synthesis of a Gemini Betaine Surfactant and Its Properties as Foam Drainage Agent.
- Author
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Hui Qi, Zhonggang Bai, Qunzheng Zhang, and Xiaojuan Lai
- Published
- 2018
- Full Text
- View/download PDF
46. Performance Evaluation and Application of the Surfactant Combinations showing Ultra-low Oil-Water Interfacial Tensions.
- Author
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Junling Tan, Yiding Shen, Xiaojuan Lai, Lei Wang, Haina Li, and Shuren Liu
- Published
- 2018
- Full Text
- View/download PDF
47. Effect of nanosilica content on properties of polyurethane/silica hybrid emulsion and its films.
- Author
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Lei Wang, Yiding Shen, Xiaojuan Lai, and Zhongjin Li
- Subjects
POLYURETHANES ,SILICA ,POLYETHERS ,ISOCYANATES ,PROPIONIC acid ,THERMOGRAVIMETRY - Abstract
Polyurethane/silica hybrid emulsion (PUSi) was synthesized by the reaction of isophorone isocyanate, polyether polyol, hydrophilic nanosilica (A200), dimethylol propionic acid, trimethylol propane, and 3‐aminopropyltriethoxysilane (KH550). The films of the waterborne polyurethane (WPU) were prepared. The structure of the polyurethane was characterized by Fourier transform infrared spectrometer (FTIR), thermogravimetry (TG), and differential scanning calorimetry (DSC). The particle size distribution and morphology of emulsion were examined. Influence of nanosilica content on the mechanical properties and solvent absorption of the cast films were also measured quantificationally. FTIR indicates that NH2of KH550 reacted with NCO of polyurethane. TG analysis indicates that nanosilica can improve thermal stability of polyurethane. There is no clear effect of nanosilica on the glass transition of soft segments. It was found that greater mechanical properties of WPU were obtained when chemical networks were formed by sol‐gel process. As the nanosilica content increases, water absorption and ethanol absorption decreased. The particle size increases with increase of A200 content. PUSi hybrid emulsions are endowed with pseudoplasticity. The apparent viscosity of emulsions increased and then decreased with addition of A200. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
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