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Despite carbon nanotubes (CNTs) have garnered tremendous research interests for enhancing the electrical and thermal conductivity of polymers, it is still a considerable challenge to achieve the uniform dispersion of carbon nanotubes in polymer matrix. Herein, inspired by the mussel-inspired chemistry, we adopted the strategy of coating CNTs with polydopamine. And the polysilsesquioxane-modified CNTs (CNTs-PSQ) were obtained based on the click chemistry reaction. The FT-IR, Raman, XRD, and TGA collectively demonstrated the successful modification of PSQ on the surface of CNTs. The incorporation of PSQ could significantly improve the dispersion of CNTs in the silicon rubbers, and a strong interfacial interaction was formed between CNTs-PSQ and silicon rubber matrix, as observed from TEM images of silicon rubber/CNTs-PSQ nanocomposites. Meanwhile, compared with the nanocomposites with neat CNTs, the ones with CNTs-PSQ exhibited simultaneously improved electrical conductivity and insulating performance. This strategy proposed for the preparation of PSQ-modified CNTs provides insights toward highly insulating and thermal conducting polymers. [ABSTRACT FROM AUTHOR]

A Ag(I)/PPh3-catalyzed chelation-controlled cycloisomerization of tryptamine-ynamide was developed to access the spiro[indole-3,4′-piperidine] scaffold in a racemic and diastereoselective manner. The diastereoselective products were achieved by a chiron approach. Density functional theory (DFT) calculations indicated that strong non-covalent effects between the substrate and catalyst/ligand complex stabilized the spiroindoleninium intermediate via cation-π–π interactions. [ABSTRACT FROM AUTHOR]

• This review presents a detailed overview of recent developments in C-MOF synthesis. • A comprehensive review of C-MOF applications in catalysis, gas adsorption and energy storage. • Potential applications and challenges of C-MOF are discussed. Within the past few decades, metal–organic frameworks (MOFs) and covalent organic frameworks (COFs) have attracted much attention due to their porous structure, periodicity, and tunability; however, the lack of good stability of MOFs limits its further application, while COFs are limited by the lack of metal active sites. Recently, a new kind of organic frameworks appeared, which used metal clusters of MOFs as secondary building units (SBUs) and synthesized covalent-metal–organic frameworks (C-MOFs) through the dynamic covalent bonding linkage of COFs. C-MOFs combine the advantages of both MOFs and COFs, and also possess the adjustable and predictable periodic porous structure, which has good stability at the and also the presence of metal active sites, which is a novel material. In this review, we provide an overview of the research advances in the synthesis strategies of C-MOFs, as well as the progress of their applications in catalysis, gas storage, and energy storage. In addition, the article ends with a look at the future direction of C-MOFs. [ABSTRACT FROM AUTHOR]

Hybrid organic framework materials are a class of hierarchical porous crystalline materials that have emerged in recent years, composed of three types of porous crystal materials, namely metal-organic frameworks (MOFs), covalent organic frameworks (COFs), and hydrogen-bonded organic frameworks (HOFs). The combination of various organic framework properties in hybrid organic frameworks generates synergistic effects, which has attracted widespread attention from researchers. The synthesis methods of hybrid organic frameworks are also an intriguing topic, enabling the formation of core-shell heterostructures through epitaxial growth, template conversion, medium growth, or direct combination. These hybrid organic framework materials have demonstrated remarkable performance in the application of photocatalytic wastewater purification and have developed various forms of applications. This article reviews the preparation principles and methods of various hybrid organic frameworks and provides a detailed overview of the research progress of photocatalytic water purification hybrid organic frameworks. Finally, the challenges and development prospects of hybrid organic framework synthesis and their application in water purification are briefly discussed. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Although laccase has a good catalytic oxidation ability, free laccase shows a poor stability. Enzyme immobilization is a common method to improve enzyme stability and endow the enzyme with reusability. Adsorption is the simplest and common method. Modified biochar has attracted great attention due to its excellent performance. Results: In this paper, cetyltrimethylammonium bromide (CTAB)-KOH modified biochar (CKMB) was used to immobilize laccase by adsorption method (laccase@CKMB). Based on the results of the single-factor experiments, the optimal loading conditions of laccase@CKMB were studied with the assistance of Design-Expert 12 and response surface methods. The predicted optimal experimental conditions were laccase dosage 1.78 mg/mL, pH 3.1 and 312 K. Under these conditions, the activity recovery of laccase@CKMB was the highest, reaching 61.78%. Then, the CKMB and laccase@CKMB were characterized by TGA, FT-IR, XRD, BET and SEM, and the results showed that laccase could be well immobilized on CKMB, the maximum enzyme loading could reach 57.5 mg/g. Compared to free laccase, the storage and pH stability of laccase@CKMB was improved greatly. The laccase@CKMB retained about 40% of relative activity (4 °C, 30 days) and more than 50% of relative activity at pH 2.0–6.0. In addition, the laccase@CKMB indicated the reusability up to 6 reaction cycles while retaining 45.1% of relative activity. Moreover, the thermal deactivation kinetic studies of laccase@CKMB showed a lower k value (0.00275 min− 1) and higher t1/2 values (252.0 min) than the k value (0.00573 min− 1) and t1/2 values (121.0 min) of free laccase. Conclusions: We explored scientific and reasonable immobilization conditions of laccase@CKMB, and the laccase@CKMB possessed relatively better stabilities, which gave the immobilization of laccase on this cheap and easily available carrier material the possibility of industrial applications. [ABSTRACT FROM AUTHOR]

It has been observed that 2,4-dichlorophenol (2,4-DCP) possesses great environmental concern for its high ecotoxicity and ubiquitousness. Adsorption is one of the simplest methods to remove the 2,4-DCP from the aqueous solutions. We conducted the synthesis of zeolite imidazolate framework-8 (ZIF-8) via a classic and facile approach as an adsorbent to remove the 2,4-DCP, while considering the superior stability and high surface area of ZIF material. The synthesized ZIF-8 material was characterized by powder X-ray diffraction, field emission-scanning electron microscope, thermal gravimetric analyses, derivative thermogravimetry, and N2 adsorption–desorption isotherms. The optimal pH conditions, adsorption kinetics, and adsorption isotherms were determined via batch adsorption equilibrium experiments. The results showed that the difference of adsorption capacity under different pH conditions could be explained via the electrostatic interaction and electrostatic repulsion between ZIF-8 and 2,4-DCP, and the optimal adsorption condition was obtained in the solution with pH 9. In addition, the Langmuir model and pseudo-second-order equation could best describe the adsorption isotherm and kinetic data, respectively. The maximum adsorption capacity was 107.07 mg/g with 50 mg/L of 2,4-DCP initial concentration at 323 K, which was comparable to some previous work. In short, it is a promising method to remove 2,4-DCP with ZIF-8 from aqueous solutions. [ABSTRACT FROM AUTHOR]

• Progress in degradation of organic pollutants by MOFs under various energy sources is described. • Differences in the catalytic process of each energy synergistic MOFs are described by comparison. • The application prospects of MOFs under various energy sources were analyzed. The removal of organic pollutants from water is a major challenge due to the ineffectiveness of traditional methods and the high level of hazard associated with these pollutants. As a result, researchers have proposed various approaches to address this issue, with particular attention being paid to the use of different energy sources for the synergistic degradation of organic pollutants. Metal-organic frameworks (MOFs) have emerged as a promising solution due to their affordability, non-toxicity and unique porous structure, which makes them highly versatile in numerous applications. Recent studies have shown that MOFs can be used to degrade organic pollutants using various energy sources. This review discusses the use of MOFs to degrade organic pollutants using light, electrical, mechanical energy, hydrogen, microwaves, electron beams and gamma rays. The performance of MOFs in each energy source is compared, and the progress of research into the catalytic degradation of organic pollutants by MOFs in the absence of external energy is detailed. Finally, this review presents the prospective application of MOFs in different energy synergies. This review aims to provide researchers with valuable insights and ideas on the use of MOFs in conjunction with various energy sources for the effective removal of organic pollutants from water. [ABSTRACT FROM AUTHOR]

In order to solve the problem of heavy metal-organic compound soil pollution, in this paper, we developed a highly efficient electro kinetic-laccase combined remediation (EKLCR) system. The results showed that the EKLCR system had an obvious migration effect on heavy metals (copper and cadmium) and good migration-degradation effect on phenanthrene. The migration rates of copper and cadmium were 48.3% and 40.3%, respectively. Especially, with the presence of laccase, the removal rate of phenanthrene on Cu2+-contaminated soil was higher than that of Cd2+-contaminated soil due to the significant effect of heavy metals on the enzymatic activity of laccase. The average migration-degradation rate of phenanthrene by EKLCR system was 45.4%. Finally, gas chromatography-mass spectrometry (GC/MS) was used to analyze the degradation intermediates of phenanthrene in the soil, which included 9,10-Phenanthrenequinone, phthalic acid, and 2,2-Biphenyldicarboxylic Acid. In addition, we give the possible degradation pathways of phenanthrene, 2,2-Biphenyldicarboxylic Acid is further degraded to produce phthalic acid. The products of the phthalic acid metabolic pathway are protocatechuic acid, pyruvic acid or succinic acid, the final products of these organic acids are carbon dioxide and water. [ABSTRACT FROM AUTHOR]

The goal of this research study is to describe academic issues which have been debated in the field of Chinese geosciences for a century. In 1922, Jonquei S. Lee (Li Siguang) discovered Quaternary glacial relics at Taihang Mountainin eastern China. In 1947, he published his research findings in the magazine Mount Lushan in Glacial Age. The research results had established three Ice Ages: Poyang (Gonzi), Dagu (Minde), and Lushan (Lisi). However, at that time, no Wurm glacial relics of the last Ice Age had been found in Lushan Mountain. Since then, the research team represented by Shi Yafeng, who is considered to be "the father of glaciers in China", questioned Jonquei S. Lee's research results and concluded that "Professor Jonquei S. Lee's Quaternary glacier research in Lushan Mountain having misread the debris flow". In 2005, the "middle‐low mountains" in eastern China were finally defined as follows: "We clearly and unambiguously believe that there were no glacial activities in the middle‐low mountainous areas of eastern China (east of 102° to 104°E; below 3,000 and 2,500 m) during the Quaternary Period". Currently, the long‐standing academic debate appears to have come to a conclusion. As of 2015, the author and others began to investigate and study the Quaternary glacial relics in Mengshan Mountain (1,156m above sea level), Shandong Province, one of the "middle‐low mountains" of eastern China. The relics have been observed to posses the systematic features of glacial erosion, trough and valley striations, and moraine deposits. The applied dating method shave confirmed that there were not only glacial relics of the last Ice Age (Wurm), but also Holocene glacial relics in the Mengshan Mountain area. Therefore, in order to further establish the corresponding relationship between the glacier, loess, stream sediment series, and MIS in the Mengshan Mountain area, a large number of chronological studies have been carried out regarding the various types of sediments in the area, and 24 dating datahave been obtained using OSL, CRN, and 14Cmethods. On this basis, the corresponding relationship between the sedimentary sequences and the MIS was established for the first time in eastern China, which in dicates the environmental changes which had occurred in eastern China since 80ka. These discoveries s and chronological study results confirm the existence of the Last Ice Age, as well as Holocene glacial relics at Mengshan Mountain, there by confirming that Quaternary glaciation had occurred in the middle‐low mountain areas of eastern China. [ABSTRACT FROM AUTHOR]

The undergraduates could practice the materials synthesis and preparation, materials processing, microstructure characterization and the properties testing of materials by the training of comprehensive experiment of novel thermoplastic vulcanizates; moreover, the undergraduates could master the basic experimental skills of the rubber composition formula, the mixing of rubber preblend, the vulcanization curve testing, the dynamic vulcanization operation, the molding of thermoplastic vulcanizate, the etching of the multiphase blend, the characterization of microstructure and the testing of the mechanical properties of thermoplastic vulcanizates, and the comprehensive experimental teaching could stimulate the comprehension of theoretical knowledge. The experimental course was of great significance for the undergraduates to in-depth understand the mixing principle of rubber preblend, the vulcanization curve of the rubber preblend, the melt blending of rubber preblend and thermoplastic resin, the dynamic vulcanization and morphology evolution of the rubber phase, the determination of etching solution and etching condition, the characterization of microstructures of the prepared blend, and the relationship between mechanical behavior and the blend composition; furthermore, it could help the undergraduates to cultivate the practical and innovation ability. [ABSTRACT FROM AUTHOR]

Contaminants in water pose a significant challenge as they are harmful and difficult to treat using conventional methods. Therefore, various new methods have been proposed to degrade organic pollutants in water, among which the photo-Fenton process is considered promising. In recent years, Fe-based metal-organic frameworks (Fe-MOFs) have gained attention and found applications in different fields due to their cost-effectiveness, non-toxic nature, and unique porous structure. Many researchers have applied Fe-MOFs to the photo-Fenton process in recent years and achieved good results. This review focuses on describing different strategies for enhancing the performance of Fe-MOFs in the photo-Fenton process. Also, the mechanism of MOF in the photo-Fenton process is described in detail. Finally, prospects for the application of Fe-MOFs in photo-Fenton systems for the treatment of organic pollutants in water are presented. This study provides information and ideas for researchers to use Fe-MOFs to remove organic pollutants from water by photo-Fenton process. [Display omitted] • Various enhancement methods of Fe-MOF in photo-Fenton process are described. • Catalytic mechanism of Fe-MOFs in photo Fenton process was discussed. • Potential application prospects and challenges of Fe-MOFs in photo Fenton process prospect. [ABSTRACT FROM AUTHOR]

Bimetallic metal-organic framework (MOF) have shown stronger catalytic activity compared with monometallic MOF. Herein, we carbonized the iron and copper bimetallic MOF to prepare the Fe-Cu-MOF@C nanocatalyst for the first time. The prepared materials were characterized by SEM, TEM, TG, VSM, XRD, and BET. Then, Fe-Cu-MOF@C was used for the degradation of 2,4-dichlorophenol (2,4-DCP) via the heterogeneous activation of persulfate (PS). The Fe-Cu-MOF@C/PS system exhibited a high catalytic activity and excellent stability. Strikingly, we found that over 99.4 % of the 2,4-DCP removal rate within 60 min and 83.4 % of the COD removal rate within 180 min in the Fe-Cu-MOF@C/PS system. The scavenger experiments and electron paramagnetic resonance (EPR) analysis revealed that SO 4 -•, •OH, •O 2 − and 1O 2 were the main reactive oxygen species (ROS) for the degradation of 2,4-DCP. Finally, the possible degradation mechanism and pathway of 2,4-DCP were given via High-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS). The enhanced catalytic performance of Fe-Cu-MOF@C/PS system could be due to the porous core-shell structure and the synergistic effect of iron and copper active species in the internal bimetallic Fe-Cu-MOF@C, which indicated the Fe-Cu-MOF@C nanocatalyst could be potentially applied in the persulfate-mediated environmental remediation. [Display omitted] • Synthesis of Fe-Cu-MOF@C nanomaterials by microwave-assisted method. • PS/Fe-Cu-MOF@C system exhibited high catalytic performance for 2,4-DCP degradation. • O 2 −• and 1O 2 are dominant oxidative species instead of SO 4 •− and •OH. • The system is suitable for a wide range of pH (2−11) and temperature (10–60 °C). [ABSTRACT FROM AUTHOR]

[Display omitted] • Laccase was immobilized onto A-MB via multi-immobilization methods. • The adsorption of MG on A-MB followed the pseudo-second-order equation. • The adsorption of MG on A-MB followed the Langmuir isotherm model. • A-MB possessed a relatively high q max (757.58 mg/g) for MG. • The maximum removal rate of immobilized laccases was high than 97.70 %. Malachite green (MG) is an environmental persistent pollutant. The excellent adsorption capacity and enzyme carrier potential of alkali modified biochar (A-MB) are potential solutions for the treatment of MG. In this paper, laccase was immobilized onto A-MB via multi-immobilization methods. The batch adsorption equilibrium experiments were conducted to study the adsorption behavior of MG on carrier A-MB. The results showed that the adsorption of MG on A-MB followed the pseudo-second-order equation and the Langmuir isotherm model. In addition, A-MB possessed a relatively high q max (757.58 mg/g) for MG. The comparative experiment was set up to compare the removal rate of MG on free laccase (FL) and immobilized laccase (adsorption method: A/lac@A-MB; adsorption-crosslinking method: A-C/lac@A-MB; covalent binding method: CB/lac@A-MB), the maximum removal rate of FL was 89.68 %, but the maximum removal rate of A/lac@A-MB, A-C/lac@A-MB and CB/lac@A-MB was 97.70 %, 98.77 % and 97.86 %, respectively. [ABSTRACT FROM AUTHOR]

Thermoplastic elastomers (TPEs) based on polypropylene (PP)/waste ethylene–propylene–diene terpolymer powder (WEPDMP) composites were prepared by melt compounding, and the composites were compatibilized by styrene–butadiene–styrene block copolymer (SBS). The effects of SBS compatibilizer on mechanical, morphological properties, and the Mullins effect of the TPEs were investigated systematically. Experimental results indicate that SBS had a good compatibilization effect on the PP/WEPDMP composites. Compared with PP/WEPDMP composites, the tensile strength and the elongation at break went through a maximum value at an SBS content of 6 phr, which were improved by 49.4 and 170.3%, respectively. Morphology study shows that the interface interaction of the PP/WEPDMP composites compatibilized by SBS was strong, which contributed to the significantly improved mechanical properties. Mullins effect results show that the softening obviously appeared after the second loading–unloading cycle, while the maximum stress decreased slightly at the later cycles and the internal friction loss of PP/SBS/WEPDMP composites was lower than that of PP/WEPDMP composites, indicating the elasticity of PP/WEPDMP TPE is improved by the incorporation of SBS. [ABSTRACT FROM AUTHOR]

Thermoplastic vulcanizates (TPVs) based on high-impact polystyrene (HIPS)/styrene–butadiene rubber (SBR) blends were prepared by dynamic vulcanization technique, and the TPVs were compatibilized by styrene–butadiene–styrene block copolymer (SBS). Experimental results indicate that SBS had a good compatibilization effect on the HIPS/SBR TPVs. A rubber process analyzer reveals that elastic modulus increased with increasing frequency and increasing SBR content in the TPVs led to obvious decrease in elastic modulus. A softening phenomenon could be observed in the stress–stretch curves of HIPS/SBR and HIPS/SBS/SBR TPVs during the uniaxial loading–unloading cycles. Compatibilized HIPS/SBR TPV had the relatively lower stress and internal friction loss. [ABSTRACT FROM AUTHOR]

Alkali modified biochar has attracted many interests as a potential enzyme immobilization carrier. In this paper, the preparation of alkali-modified immobilized laccases under multi-immobilization methods (adsorption: A/lac@A-MB; adsorption-crosslinking: A-C/lac@A-MB; covalent bonding: CB/lac@A-MB) were optimized via Design-Expert for the first time, and the stability of alkali-modified immobilized laccases was compared with other literatures. In addition, SEM, BET, FT-IR and XRD analyses were used to characterize the prepared immobilized enzyme samples. The results showed that the three kinds of immobilized laccases have improved the stability to different degrees relative to free laccase. In the pH range of 3–7, temperature range of 25–55 °C, and storage for more than 30 days, after 5 reaction cycles, the relative activity of the laccase immobilized on three different supports can still be greater than 50%. In addition, CB/lac@A-MB obtained the highest Vmax (0.94 U/mg), specific activity (0.66 U/mg) and activity recovery (66.20%); A-C/lac@A-MB obtained the highest immobilization yield (67.40%) and enzyme loading (180.81 mg/g); and A/lac@A-MB obtained the lowest K m of 140 μM. The above results are comparable to other reports, aiming to provide a reference for practical application of different methods of immobilized laccase in the industrial field. [Display omitted] • Laccase was immobilized in alkali-modified biochar via three different methods. • The immobilized laccases have improved the stability in pH, storage, etc. • CB/lac@A-MB obtained the highest Vmax, specific activity and activity recovery. • A-C/lac@A-MB obtained the highest immobilization yield and enzyme loading. • A/lac@A-MB obtained the lowest K m of 140 μM. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel metal–carbon nanocomposite (Cu-HAP/SiO 2 @carbon) was synthesized as a catalyst to remove 2,4-DCP. • Cu-HAP/SiO 2 @carbon surface has a rich pore structure and a high specific surface area. • The removal of 2,4-DCP conforms to first-order kinetics (k = 0.06331 mol/L∙min). • Cu-HAP/SiO 2 @carbon broadens the applicable pH range of H 2 O 2. • The removal rate of 93.73% can still be maintained after 5 times of reuse. Hydroxyapatite (HAP) has stable ion exchange capacity and is a potential environmental catalyst carrier. In this paper, a novel metal–carbon nanocomposite (Cu-HAP/SiO 2 @carbon) was synthesized as a catalyst to remove 2,4-DCP. The SEM, XRD, FT-IR, XPS and BET were used to characterize the synthesized catalyst materials, the results showed that Cu-HAP/SiO 2 @carbon has a rich pore structure and a high specific surface area, and the copper element is well dispersed on the surface of the carrier. The results of 2,4-DCP removal effect showed that almost 100 % of 2,4-DCP was removed under the optimal reaction conditions. In addition, the Cu-HAP/SiO 2 @carbon broaden the applicable pH range and has excellent performance in terms of reusability (93.73 % of removal rate after 5 cycles). Finally, based on the intermediate products identify by HPLC, the degradation mechanism and possible degradation pathway of 2,4-DCP was investigated, EPR was employed to confirm the effects of ·OH. [ABSTRACT FROM AUTHOR]

Abstract: Thermoplastic elastomer (TPE) based on high impact polystyrene (HIPS)/ethylene-vinyl acetate copolymer (EVA)/waste ground rubber tire (WGRT) powder composites were prepared by melt-compounding, and the composites were compatibilized by styrene-butadiene-styrene block copolymer (SBS). The effects of SBS compatibilizer on mechanical properties and morphological properties of the composites were investigated systemically. Experimental results indicate that SBS had a good compatibilization effect on the HIPS/EVA/WGRT composites. Compared with HIPS/EVA/WGRT composites, the tensile strength and the elongation at break went through maximum values at a compatibilizer resin content of 12 phr, which were improved by 145% and 1280%, respectively. Morphology study shows that the interface interaction was strong in the HIPS/EVA/WGRT composites compatibilized by SBS, which contributed to the significantly improved mechanical properties. Payne effect could be found in the strain sweep of HIPS/EVA/SBS/WGRT composites, which was related to the variation of interface interaction. The increasing dosage of SBS compatibilizer in the HIPS/EVA/WGRT composites weaken the Payne effect and led to the slow decrease of storage modulus. [Copyright &y& Elsevier]

Compatibilized Cis-1,3-butadiene rubber (BR)/ethylene-vinyl acetate copolymer (EVA)/high-impact polystyrene (HIPS) thermoplastic blend vulcanizates (TPVs) were prepared by dynamic vulcanization, with TPVs being compatibilized by styrene-butadiene-styrene (SBS) block copolymer. The effects of SBS compatibilizer on mechanical, dynamic mechanical, and morphological properties of TPVs were investigated systematically. Experimental results indicated that the dynamically vulcanized BR/HIPS blends did not show an elastomeric behavior when the BR/HIPS blend ratio ranged from 30:70 to 70:30. However, the dynamically vulcanized BR/EVA/HIPS blends compatibilized with SBS showed obvious elastomeric behavior; thus SBS had a good compatibilization effect on BR/EVA/HIPS TPVs. The fractured surface morphology of compatibilized BR/EVA/HIPS TPV was relatively smooth, the interface interaction was strong, and there was no obvious micro-phase separation. BR particles were dispersed evenly in the etched surfaces of BR/EVA/SBS/HIPS TPV. A rubber process analyzer revealed that the storage modulus decreased significantly with increasing strain and the incorporation of compatibilizer SBS in TPVs weakened the Payne effect; the loss modulus showed a pronounced peak and tanδ increased continuously with increasing strain. [ABSTRACT FROM PUBLISHER]

Abstract: Thermoplastic vulcanizates (TPVs) based on high density polyethylene (HDPE)/ethylene–propylene diene copolymer (EPDM) blends with different compositions of polyethylene–octene elastomer (POE) were prepared by dynamic vulcanization, the effects of the POE incorporation on deformation reversibility enhancement, mechanical, dynamic mechanical and morphological properties of the TPVs were investigated systematically. Characterization via FE-SEM confirms the tearing strips on the fracture surface of HDPE/EPDM TPVs were formed by the residual plastic deformation of HDPE lamellae crystals, which also resulted in the relatively high permanent deformation of TPVs. The elasticity of TPV matrix was improved greatly by the incorporation of POE and the tension set was decreased obviously. RPA results show that the increasing frequency led to the increased elastic modulus while the incorporation of POE in matrix led to the decreased elastic modulus. The tan δ decreased continuously with the increasing frequency and the incorporation of POE had a non-ignorable influence on the tan δ of HDPE/EPDM TPVs. [Copyright &y& Elsevier]

Exothermal montmorillonite (EMMT) was prepared and used in the preparation of HDPE composites in which the EMMT was intercalated. Compared with the ODA modified montmorillonite (OMMT), EMMT exhibited better intercalation behavior during melt compounding, resulting in similar tensile modulus and better tensile strength and elongation at break of the corresponding composites. The crystallization of the polymeric matrix and the dispersion of MMT were systemically investigated; their relationship with the mechanical properties of the composites are discussed as well. [ABSTRACT FROM AUTHOR]

Abstract: Thermoplastic vulcanizates (TPVs) based on polyethylene–octene elastomer (POE)/ethylene–propylene diene copolymer (EPDM) blends were prepared by dynamic vulcanization, the effects of the EPDM incorporation on mechanical, dynamic mechanical and morphological properties of the TPVs were investigated systemically. Experimental results indicate that compared with pure POE, the improvement of mechanical properties of POE/EPDM blends was achieved; the tensile strength and tearing strength reached the maximum at an EPDM content of 20wt.%. It is interesting to note that the tensile set at break was decreased almost linearly with increasing EPDM loading, decreasing from 190% (at 0phr EPDM) to 55% (at 30wt.% EPDM), indicating the relatively large permanent deformation of POE is improved remarkably by the incorporation with EPDM. Phase contrast microscopy studies show that the vulcanized EPDM particles were uniformly dispersed in the POE matrix. RPA results show that the elastic modulus increased with increasing frequency, moreover, it is noteworthy that the storage modulus of dynamically vulcanized POE/EPDM blends was higher than that of pure POE, however, the storage modulus decreased with increasing EPDM content, the incorporation of EPDM had almost no influence on the tan δ. [ABSTRACT FROM AUTHOR]

Thermoplastic vulcanizates (TPVs) based on styrene-butadiene rubber (SBR)/ethylene-vinyl acetate copolymer (EVA)/high-impact polystyrene (HIPS) blends were prepared by dynamic vulcanization, and the TPVs was compatibilized by styrene-butadiene-styrene block copolymer (SBS). The effects of SBS compatibilizer on mechanical, dynamic mechanical, and morphological properties of the TPVs were investigated systemically. Experimental results indicate that SBS had a good compatibilization effect on the SBR/EVA/HIPS TPVs. The tensile strength went through a maximum value at a compatibilizer resin content of 6 phr, and the elongation at break and tear strength increased with increasing SBS content. Morphology study shows that the vulcanized SBR particles were dispersed in the HIPS matrices. A rubber process analyzer reveals that the elastic modulus increased with increasing frequency and the incorporation of EVA in the TPVs led to the obvious decrease of elastic modulus; however, the further addition of compatibilizer SBS affected the elastic modulus less. The tan δ decreased continuously with increasing frequency. The addition of SBS in the TPVs led to enhanced hysteresis behavior and relatively high tan δ. [ABSTRACT FROM AUTHOR]

This paper combines the perspectives of psychologists, who have emphasized procrastination, and academics in other disciplines, who have emphasized class attendance, in explaining student performance. The analysis measures the relative contribution of each of two separate measures of academic procrastination and class attendance in accounting for differences in several measures of academic performance (grades in the completion of eleven homework assignments, an online mid-term exam and a final exam) among students in an introductory statistics course. Multiple regression models are developed to explain differences in these performance measures based on the above student behavior variables and control variables accounting for student characteristics. Although the class attendance variable was most often found to be directly associated with student performance, neither the statistical significance nor relative strength of this relationship was found to be as strong as the affect of the start and submission measures of student procrastination, particularly the latter measure. The implications of these results for the application of a more realistic student perspective in introductory statistics and faculty course design strategies are considered. [ABSTRACT FROM AUTHOR]

The nucleation activation of TiO2 nanoparticles in the linear low-density polyethylene (LLDPE)/low-density polyethylene (LDPE)/TiO2 nanocomposites prepared by non-isothermal crystallization, the spherical crystals morphology of the etched LLDPE/LDPE and LLDPE/LDPE/TiO2 composites were investigated by differential scanning calorimetry (DSC) and field-emission scanning electron microscopy (FE-SEM), respectively. The results showed that the heterogeneous nucleation activation of TiO2 nanoparticles was accelerated by the fast cooling rate. The spherical crystals in the LLDPE/LDPE and LLDPE/LDPE/TiO2 composites were ascribed to the same crystal structure. It was worth to note that there was distinct difference between the morphology of the cocrystallization LLDPE/LDPE crystals and that of the independent crystallization LLDPE/LDPE crystals. [ABSTRACT FROM AUTHOR]

Abstract: Organically modified montmorillonite (OMMT) nanoparticles were obtained by hydrothermal reaction and exfoliated nylon-6/montmorillonite nanocomposites were prepared by melt-compounding. The morphology of the OMMT nanoparticles was observed by field-emission scanning electron microscopy (FE-SEM). The exfoliated OMMT nanoparticles consisted of several parallel MMT layers and presented disordered and villiform morphology. Energy dispersive X-ray spectrometry (EDX) indicates that OMMT nanoparticles were dispersed uniformly in the nylon-6 matrix. Atomic force microscopy (AFM) shows that the OMMT nanoparticles in nanocomposites were dispersed in nanoscale and arranged along the injection direction. Mechanical tests show that, upon incorporation of only 2 wt.% OMMT, the impact strength of nylon-6 was greatly improved whereas other properties were only slightly improved. [Copyright &y& Elsevier]

Propylene-ethylene copolymer/calcium carbonate (CaCO3) composites (weight ratio=50/50) toughened with high density polyethylene (HDPE) were prepared using a twin-screw extruder; the HDPE content in composites was in the range of 0-4 wt.%. The notched impact strength of propylene-ethylene copolymer/CaCO3 composites with 1.5 wt.% HDPE was 46% higher than that of propylene-ethylene copolymer/CaCO3 composites. Differential scanning calorimetry (DSC) experiments showed that good miscibility between propylene-ethylene copolymer and HDPE enhanced the interpenetration of the macromolecules located in the interface. It was shown that debonding of the small HDPE particles within the propylene-ethylene copolymer matrix resulted in the formation of small voids; the subsequent plastic deformation of the propylene-ethylene copolymer matrix next to the voids thinned the ligaments and led to large energy consumption. [ABSTRACT FROM AUTHOR]

The rheology and dispersion behavior of ethylene-vinyl acetate (EVA) copolymer/TiO2 masterbatches prepared by melt-compounding were investigated. The pure EVA exhibits obviously pseudoplastic behavior and the apparent viscosity decreases remarkably at experimental temperatures, especially in the range of 100–500 s-1. The EVA/TiO2 masterbatches exhibit similar shear rheology behavior with pure EVA and the apparent viscosities are obviously higher than that of pure EVA when the TiO2 content is above 10 wt.%. Field-emission scanning electron microscopy (FE-SEM) and energy dispersive x-ray spectroscopy (EDX) show that relatively low TiO2 loading and moderate shear rate are helpful for the improvement of dispersion behavior of TiO2 nanoparticles; moreover, the dispersion behavior of TiO2 greatly influences the melt viscosity. The extensional rheology of pure EVA decreases with increasing extension rate, especially at low melt temperatures. EVA/TiO2 masterbatches have similar extensional rheology behavior as pure EVA and the TiO2 loading has almost no influence on the extensional viscosity of materbatches. [ABSTRACT FROM AUTHOR]

The extensional rheology and dispersion behavior of high impact polystyrene (HIPS) and HIPS/TiO2 nanocomposites prepared by melt‐compounding were investigated. The influence of ethylene‐vinyl acetate (EVA) copolymer on the extensional rheology of HIPS/TiO2 masterbatches was also researched. The rheological experiments investigated with Rosand Presicion Rheometer confirmed that the HIPS/TiO2 masterbatches, the HIPS/EVA/TiO2 masterbatches and the HIPS/TiO2 nanocomposites with low TiO2 loading shown different extensional rheology in comparison to the pure HIPS. Field‐emission scanning electron microscopy (FE‐SEM) shown the dispersion morphology of TiO2 nanoparticles in HIPS based nanocomposites and indicated the influence of TiO2 dispersion behavior on the unusual extensional rheology of HIPS nanocomposites. [ABSTRACT FROM AUTHOR]

Interconnected polyaniline nanofibers with diameters in the range of 30–60 nm and lengths up to several micrometers have been synthesized by chemical oxidative polymerization of aniline in catanionic solution by mixing cetyltrimethylammonium bromide and sodium dodecylbenzenesulfonate. The product was characterized by field‐emission scanning electron microscopy, transmission electron microscopy, UV‐vis spectroscopy, and Fourier transform infrared spectroscopy. The effects of the molar fraction of cetyltrimethylammonium bromide on the morphologies of polyaniline have been investigated. [ABSTRACT FROM AUTHOR]

The glass transition and free volume of high impact polystyrene (HIPS)/TiO 2 nanocomposites are investigated by dilatometry, along with the influence of free volume variation on rheological behavior and deformation temperature. Transmission electron microscopy (TEM) and field‐emission scanning electron microscopy (FE‐SEM) show the presence of monodispersed nanoparticles and small agglomerated particles. The glass transition temperature ( T g ) of nanocomposites containing 1–3 wt% TiO 2 is slightly lower than that of HIPS. The enhanced segmental motion of HIPS molecules located in the interface region results in the occurrence of extra free volume and the depression of T g . The thermal expansion coefficient of HIPS increases with increasing TiO 2 content and is obviously higher that of the free volume in the nanocomposites. Furthermore, the abnormal variation in rheological behavior and deformation temperature is consistent with the increase of free volume. [ABSTRACT FROM AUTHOR]

Abstract: The focus of the letter is to investigate the influence of calcium carbonate (CaCO3) nanoparticles on the rheology enhancement of polycarbonate (PC) melt. The PC/CaCO3 nanocomposites with different compositions of CaCO3 were prepared by melt-compounding. Characterizations via energy-dispersive X-ray spectrometer (EDS) and field-emission scanning electron microscopy (FE-SEM) confirm the random dispersion of CaCO3 in the PC/CaCO3 masterbatch. The rheological experiments investigated with Rosand Presicion Rheometer show the remarkable rheology enhancement of PC melt due to the addition of CaCO3 nanoparticles. Mechanical tests show that, upon incorporation of only 1 wt.% CaCO3, the tensile modulus, the bending modulus, and the bending strength of PC are improved; however, the tensile strength and elongation at break are depressed. [Copyright &y& Elsevier]

Nonisothermal crystallization kinetics of ethylene–acrylic acid copolymer (EAA) and thermoplastic vulcanizate (TPV) based on EAA/chloroprene rubber (CR) were extensively studied using differential scanning calorimetry. Several methods, including the Avrami, Ozawa, and Mo equations, were carried out to analyze the process of nonisothermal crystallization kinetics of EAA and EAA/CR TPV. The results showed that the Avrami analysis modified by Jeziorny and a method developed by Mo could describe the nonisothermal crystallizations of pure EAA and the EAA/CR TPV very well. However, the Ozawa analysis did not give an adequate description. The crystallization processes of pure EAA and the EAA/CR TPV were accelerated by increasing the cooling rates. Moreover, the initial crystallization temperature and the crystallization termination temperature of EAA/CR TPV were higher than those of pure EAA at the same cooling rate, thus showing the nucleating function of CR in the beginning. While the crystallization half time of EAA/CR TPV was apparently longer than that of pure EAA, meaning that the more CR could cause the steric effect and retard the crystallization process of the TPV during the late stages of crystallizing. Although the CR phase of EAA/CR TPV could provide more nucleation sites, the presence of more CR phase must impose a much more significant confinement effect on the crystal growth of EAA. It was believed that this confinement effect overweighed the nucleation effect, thereby slowing down the overall crystallization rate. [ABSTRACT FROM AUTHOR]

Urban tourism is considered a complex system, and multiscale exploration of the organizational patterns of attraction networks has become a topical issue in urban tourism, so exploring the multiscale characteristics and connection mechanisms of attraction networks is important for understanding the linkages between attractions and even the future destination planning. This paper uses geotagging data to compare the links between attractions in Beijing, China during four different periods: the pre-Olympic period (2004–2007), the Olympic Games and subsequent 'heat period' (2008–2013), the post-Olympic period (2014–2019), and the COVID-19(Corona Virus Disease 2019) pandemic period (2020–2021). The aim is to better understand the evolution and patterns of attraction networks at different scales in Beijing and to provide insights for tourism planning in the destination. The results show that the macro, meso-, and microscales network characteristics of attraction networks have inherent logical relationships that can explain the commonalities and differences in the development process of tourism networks. The macroscale attraction network degree Matthew effect is significant in the four different periods and exhibits a morphological monocentric structure, suggesting that new entrants are more likely to be associated with attractions that already have high value. The mesoscale links attractions according to the common purpose of tourists, and the results of the community segmentation of the attraction networks in the four different periods suggest that the functional polycentric structure describes their clustering effect, and the weak links between clusters result from attractions bound by incomplete information and distance, and the functional polycentric structure with a generally more efficient network of clusters. The pattern structure at the microscale reveals the topological transformation relationship of the regional collaboration pattern, and the attraction network structure in the four different periods has a very similar importance profile structure suggesting that the attraction network has the same construction rules and evolution mechanism, which aids in understanding the attraction network pattern at both macro and micro scales. Important approaches and practical implications for planners and managers are presented. [ABSTRACT FROM AUTHOR]

Abstract: A simple route that utilizes carbon nanofibers as templates for preparing metal or alloy nanotubes via electroless deposition is developed. SEM and TEM images of the prepared Ni–Ni3P nanotubes are presented. In this method, it is easy to control the size or the shape of the prepared metal nanotubes by using different carbon or other nanofibers as templates. [Copyright &y& Elsevier]

A simple, effective and inexpensive method was proposed to reuse ground tire rubber (GTR) powder by preparing a superhydrophobic surface via a molding process. The obtained superhydrophobic surface was based on low-density polyethylene (LDPE) / ground tire rubber (GTR) thermoplastic elastomers (TPEs) where the styrene-butadiene-styrene block copolymer (SBS) was used as compatibilizer and series sandpapers were used as templates. The mechanical properties, hydrophobic properties, surface morphology and self-cleaning property were investigated systematically. The results showed that both of the mechanical properties and superhydrophobicity could be greatly improved with a certain amount of SBS. The superhydrophobic surface based on molded LDPE/SBS/GTR (weight ratio = 40/15/60) TPE exhibited excellent superhydrophobicity (with a contact angle of 164.6° ± 3.0° and a tilt angle of 4.4° ± 1.9°). Furthermore, abundant tearing microstructure could be found obviously by morphology observation. Optical images indicated the surface possessed of low adhesion force and self-cleaning property. [ABSTRACT FROM AUTHOR]

Thermoplastic vulcanizate (TPV) made from the ethylene-vinyl acetate copolymer (EVA)/nitrile rubber (NBR) blend was fabricated using the dynamic vulcanization method. Differential scanning calorimetry (DSC) was utilized to analyze the nonisothermal crystallization kinetics of both pure EVA and EVA/NBR TPV. The nonisothermal crystallization mechanism was evaluated using the Avrami method modified by Jeziorny, the Ozawa method and the Mo method. The results demonstrate that the nonisothermal crystallization of both pure EVA and EVA/NBR TPV can be adequately described by the Avrami method modified by Jeziorny and the Mo method, while the Ozawa method is not applicable. By elevating the cooling rate, there was a reduction in the crystallization temperature and t1/2 for both pure EVA and EVA/NBR TPV, while the degree of crystallization increased. At the same cooling rate, the crystallization temperature of the EVA/NBR TPV was found to be higher than that of the pure EVA, suggesting that the presence of NBR facilitated the nucleation of the EVA matrix within the EVA/NBR TPV. Moreover, a steric hindrance effect existed in the NBR phase of EVA/NBR TPV at the same cooling rate, resulting in a larger t 1/2 compared to that of the pure EVA, indicating hindered crystal growth. [ABSTRACT FROM AUTHOR]

Chronic allograft vasculopathy (CAV) remains a predominant contributor to late allograft failure after organ transplantation. Several factors have already been shown to facilitate the progression of CAV, and there is still an urgent need for effective and specific therapeutic approaches to inhibit CAV. Human mesenchymal-like endometrial regenerative cells (ERCs) are free from the deficiencies of traditional invasive acquisition methods and possess many advantages. Nevertheless, the exact immunomodulation mechanism of ERCs remains to be elucidated. C57BL/6 (B6) mouse recipients receiving BALB/c mouse donor abdominal aorta transplantation were treated with ERCs, negative control (NC)-ERCs and interleukin (IL)-37−/−ERCs (ERCs with IL-37 ablation), respectively. Pathologic lesions and inflammatory cell infiltration in the grafts, splenic immune cell populations, circulating donor-specific antibody levels and cytokine profiles were analyzed on postoperative day (POD) 40. The proliferative capacities of Th1, Th17 and Treg subpopulations were assessed in vitro. Allografts from untreated recipients developed typical pathology features of CAV, namely endothelial thickening, on POD 40. Compared with untreated and IL-37−/−ERC-treated groups, IL-37–secreting ERCs (ERCs and NC-ERCs) significantly reduced vascular stenosis, the intimal hyperplasia and collagen deposition. IL-37–secreting ERCs significantly inhibited the proliferation of CD4+T cells, reduced the proportions of Th1 and Th17 cells, but increased the proportion of Tregs in vitro. Furthermore, in vitro results also showed that IL-37–secreting ERCs significantly inhibited Th1 and Th17 cell responses, abolished B-cell activation, diminished donor-specific antibody production and increased Treg proportions. Notably, IL-37–secreting ERCs remarkably downregulated the levels of pro-inflammatory cytokines (interferon-γ, tumor necrosis factor-α, IL-1β, IL-6 and IL-17A) and increased IL-10 levels in transplant recipients. The knockdown of IL-37 dramatically abrogates the therapeutic ability of ERCs for CAV. Thus, this study highlights that IL-37 is indispensable for ERC-mediated immunomodulation for CAV and improves the long-term allograft acceptance. [ABSTRACT FROM AUTHOR]

Thermoplastic vulcanizates (TPVs) based on ethylene-methacrylic acid (EMA) copolymer/nitrile butadiene rubber (NBR) blends were prepared by dynamic vulcanization where the NBR phase was reinforced by zinc dimethacrylate (ZDMA). The effect of ZDMA dosage on the mechanical properties, Mullins effect, and morphology of the TPVs was investigated systematically. Experimental results indicated that the mechanical properties of EMA/NBR TPVs were enhanced remarkably with the incorporation of ZDMA. Morphology study showed that the NBR particles with diameters of about 1–5 μm were dispersed evenly in the etched surface of EMA/NBR/ZDMA TPV. The Mullins effect could be observed in the stress–strain curves of EMA/NBR TPV and EMA/NBR/ZDMA TPV during the uniaxial loading–unloading cycles. Compared with those of EMA/NBR TPV, EMA/NBR/ZDMA TPV had the higher stress, residual deformation, and internal friction loss. [ABSTRACT FROM AUTHOR]

As a typical chlorophenol, 2,4,6-trichlorophenol (2,4,6-TCP) is highly toxic and difficult to degrade. Here, we prepared a novel material (Cu/HAP@sBC) by combining copper-based hydroxyapatite with biochar, which removes 2,4,6-TCP via activated persulfate (PS). Cu/HAP@sBC was tested using various characterization methods. In addition, the removal of 2,4,6-TCP was up to 100% after 60 min, and the Cu/HAP@sBC/PS system had a broad pH application range (3−10). Based on the results, SO 4 −•, •OH, •O 2 −, and 1O 2 were the main reactive species. Finally, the possible degradation pathways of 2,4,6-TCP were explored based on the intermediates identified by high-performance liquid chromatography-mass spectrometry (LC-MS). [Display omitted] • A new Cu/HAP@sBC/PS system for degradation of 2,4,6-TCP was established. • High degradation rates over a wide pH range (3–10). • The study identified active species were SO 4 −•, •OH, •O 2 −, and 1O 2. • The degradation mechanism of 2,4,6-TCP was proposed. [ABSTRACT FROM AUTHOR]

Recently developed covalent functionalization of chemically exfoliated MoS2 (typically in alkyl lithium) allows the formation of chalcogenide‐carbon bonds by reacting with organohalides and aryl diazonium salts. We herein develop a novel method for the covalent functionalization of MoS2 to yield dodecylated MoS2 via reductive activation in a strongly reducing sodium‐naphthalene solution and using alkyl sulfide as an electrophile. Dodecylated MoS2/polystyrene (PS) composites fabricated by solution casting method. Dodecyl chains are grafted successfully onto MoS2 nanosheets, which gives rise to the exfoliation level of few‐layer thickness and matched compatibility with the host polymeric matrix. The inclusion of dodecylated MoS2 at a concentration of 1.0 wt% yields a substantial improvement in both Young's modulus and tensile strength, with a 106.7% increase and a 67% enhancement, respectively, as compared to the performance of pure PS. The enhanced mechanical characteristics can be credited to the uniform dispersion of dodecylated MoS2 within the PS matrix and enhanced interfacial interaction between the PS material and the filler. The composites demonstrate a significant increase in their glass transition temperature (Tg). Notably, the dodecylated MoS2/PS (1.0 wt%) composite exhibits a 59.8% elevation in storage modulus when compared to pure PS. The coke yield of dodecylated MoS2/PS (1.0 wt%) reaches 2.7%, much larger than the value (only 0.2%) for pure PS. The novel functionalization might expedite the applications of molybdenum disulfide in diverse fields. Highlights: A novel method for the covalent functionalization of MoS2.Dodecylated MoS2/PS composites were fabricated via solution casting method.Ultrathin structure of MoS2 nanosheets was obtained after functionalization.Composites improvement in Young's modulus and tensile strength compared to PS.The composites show significant enhancements in Tg. [ABSTRACT FROM AUTHOR]

Thermoplastic vulcanizates (TPVs) based on polylactide (PLA)/nitrile butadiene rubber (NBR) blends were prepared by dynamic vulcanization where the PLA phase was plasticized by dioctyl phthalate (DOP), and the influence of DOP dosage on mechanical properties, morphology evolution, Mullins effect, and its reversibility were investigated systematically. The experimental results indicated that the mechanical properties of PLA/NBR TPVs were improved significantly with the addition of DOP. Compared with that of the PLA/NBR TPVs, the Shore A hardness was decreased obviously, while the elongation at break was increased slightly with increasing DOP dosage. Mullins effect results showed that the TPVs incorporated with DOP had the relatively lower stress-softening effect. The recovery ability of the maximum stress could be remarkably enhanced by increasing heat treatment temperature. Morphology studies showed that the network microstructure of the co-continuous phases was denser with the increasing dynamic vulcanization time; however, the network microstructure of the co-continuous was changed slightly with the addition of DOP. [ABSTRACT FROM AUTHOR]

Achieving considerable shape-memory effects is a challenge for typical sea-island structured polymer blends. In this article, we successfully fabricated a novel heat-triggered shape-memory polymer (HSMP) based on ethylene–vinyl acetate copolymer/nitrile–butadiene rubber (EVA/NBR) thermoplastic vulcanizates (TPVs) via dynamic vulcanization. The influence of deformation temperature (T d), recovery temperature (T r), and recovery time on the shape-memory behavior of the EVA/NBR (weight ratio = 80/20) TPV was investigated systematically. The shape-memory result of the EVA/NBR (weight ratio = 80/20) TPV demonstrated that when the T d was close to the melting temperature (T m) of the EVA phase (76°C), the TPV could obtain a good shape fixity ratio (>95%) and an excellent shape recovery ratio (>95%) at 100% stretch ratio. A shape-memory mechanism was proposed for this HSMP. The dynamic mechanical analysis results under temperature sweep mode showed that with increasing EVA content in TPVs, the tan δ decreased, while the storage modulus increased. The morphology observation showed that the cross-linked NBR particles were dispersed evenly in the etched surface of EVA/NBR TPV with an average diameter of approximately 2–6 μm. The longitudinal stretching surface of the EVA/NBR TPV exhibited the banding-like texture microstructure during the stretching process. [ABSTRACT FROM AUTHOR]

Super-hydrophobic and super-oleophilic surface based on high-density polyethylene/styrene–butadiene–styrene block copolymer/waste ground rubber tire powder thermoplastic elastomer (TPE) was successfully prepared while metallographic sandpaper was used as a template. Field emission scanning electron microscope study showed that the molded TPE surface with W7 grade sandpaper possessed the rough microstructure; moreover, the micrometer scale strips resulting from the plastic deformation of TPE matrix could be observed obviously, leading to the increasing surface roughness. Wettability tests showed that the molded TPE surfaces with series sandpapers exhibited the hydrophobic and super-oleophilic properties; moreover, the surface molded with W7 grade sandpaper showed the remarkable super-hydrophobic and super-oleophilic properties. [ABSTRACT FROM AUTHOR]

Thermoplastic vulcanizates (TPVs) of ethylene-acrylic acid copolymer (EAA)/chloroprene rubber (CR) were prepared by dynamic vulcanization, and the mechanical properties, microstructure, Mullins effect and reversible responses of the prepared EAA/CR TPVs were investigated systematically under the compression mode. Experimental results showed that the EAA/CR TPV with 40/60 weight ratio had the excellent mechanical properties. The crosslinked CR particles with average diameter of 3 ~ 6 µm were dispersed evenly in the etched surface of EAA/CR TPV. Mullins effect could be observed in the stress–strain curves of TPVs during the uniaxial loading–unloading cycles. Compared with the EAA/CR TPV with 30/70 weight ratio, the EAA/CR TPV with 40/60 weight ratio had the relatively larger maximum stress, residual deformation, internal friction loss, degree of stress softening effect and tanδ value at specific strain. Meanwhile, the reversibility of the Mullins effect showed a temperature-dependent feature and was enhanced with increasing heat treatment temperature. [ABSTRACT FROM AUTHOR]

[Display omitted] • The research progress of MFe 2 O 4 -based catalysts is reviewed. • Catalytic activity may be related to crystal field stablization energies. • Accelerating Fe2+/Fe3+ cycle by carbon-based materials injecting electrons. • A large number of data are visualized to analyze catalytic activity. In recent years, the removal of organic pollutants in water has become a research hotspot for the scientific community. Advanced oxidation processes (AOPs) are effective ways to remove organic pollutant in water. Among them, the photo-Fenton process, as a simple, efficient, and clean catalytic method, has been widely applied. In the process of exploring photo-Fenton catalysts, spinel ferrites (MFe 2 O 4 , M = Cu, Co, Ni, Zn, Mn, etc.) has attracted more and more attentions because of its rich surface active sites, low price, better light-corrosion resistance, and outstanding recoverability. However, the relatively narrow band gap easily causes the rapid recombination of photo-generated electron-hole pairs, which seriously hinders the high catalytic activity of MFe 2 O 4 catalysts. To improve the catalytic effect of MFe 2 O 4 materials in wastewater treatment, this paper summarizes the problems faced in the photo-Fenton process when pure MFe 2 O 4 as catalysts and it is found that the catalytic activity may be determined by the crystal field stabilization energy. Most importantly, the effective ways to improve the catalytic performance are discussed in detail, including element doping and coupling with carbon-based materials. And a possibility is proposed that the formation of n-type semiconductors by multi-electron doping is beneficial to promote Fe2+/Fe3+ cycle. Additionally, the order of factors affecting the degradation performance is determined in practical application, which will lay a foundation for the design of MFe 2 O 4 -based catalysts in the future. [ABSTRACT FROM AUTHOR]

Design of shape memory polymers (SMPs) based on thermoplastic vulcanizates (TPVs) is considered a challenge because, in most cases, the phase interface of TPV is not powerful enough to perform the shape memory behavior. In this work, a facile and effective strategy was designed to achieve rapidly reconfigurable shape fixity and recovery for a heat-triggered shape memory polymer (HSMP), which was derived from a typical sea-island structured ethylene-vinyl acetate copolymer/nitrile-butadiene rubber (EVA/NBR) TPVs via Zinc Dimethacrylate (ZDMA) induced interfacial compatibilization. The EVA phase served as the heat-control switched phase to fix the deformation status of rubber particles via the ZDMA-enhanced interface. With the incorporation of ZDMA, the average diameter of NBR particles was reduced to 3–5 μm, which markedly enlarged EVA/NBR interfacial contact surfaces. The enhanced interface improved stress delivery efficiency between EVA and NBR phases, which further improved the shape recovery (SR) and shape fixing (SF) ability of TPVs. This novel HSMP exhibited the surprising shape memory property (shape fixities ~ 95%, shape recoveries> 95%, and fast recovery speed < 20 s at the switching temperature of 95 °C). The dynamic mechanical behavior and stress relaxation behavior of EVA/NBR/ZDMA TPVs were characterized, and the results demonstrated that the high modulus value and the low stress relaxation ratio supported the improvement of SF and SR ratios of the EVA/NBR/ZDMA TPVs. This novel HSMP is expected to open up a wide range of potential applications in smart devices. • The incorporation of ZDMA enhanced the cross-linking density and promoted the cross-linking rate of NBR. • The incorporation of ZDMA significantly enlarged the contact surface between the EVA and NBR phases. • Shape memory effect of the composites was successfully improved via ZDMA induced interfacial compatibilization. • Higher modulus value and lower stress relaxation ratio contributed to the realization of shape memory behavior. • SEM characterization exhibited remarkable orientation textures on the surface of specimen. [ABSTRACT FROM AUTHOR]

The Mullins effect during uniaxial compression tests, together with its reversibility, of ethylene-vinyl acetate copolymer (EVA)/nitrile-butadiene rubber (NBR)/zinc dimethacrylate (ZDMA) thermoplastic vulcanizates (TPVs) were investigated systematically. The experimental results indicated that the Mullins effect could be observed during the cyclic uniaxial compression tests and was accompanied with stress softening, residual deformation accumulation and hysteresis. The reversibility of the Mullins effect showed a temperature-dependent feature and was enhanced with increasing temperature. [ABSTRACT FROM AUTHOR]

Although the construction of superwettability materials for oil-water separation has become a research hotspot, it is still a thorny issue due to its easy pollution to the environment during the preparation process. In this paper, we reported the functional PP/EPDM TPV film (with a contact angle of oil and water is 0° and 157.9±2.9°) as superhydrophobic and superoleophilic materials with reproducible processing characteristics at high temperature; moreover, during the molding process the etched aluminum foil was used as a template for the preparation of functional TPV film which was used in the efficient separation treatment of oily wastewater. It should be noted that a novel method was proposed for the continuous oil-water separation via a pressure response through valve, which was different from the traditional gravity-driven method and the permeable oil-water separation. The flexible PP/EPDM TPV film was rolled up and loaded into the through valve and the gap between films was used as the pressure response channel of oil-water separation. The novel functional TPV film used in the continuous oil-water separation was recyclable, environmentally friendly, and easy to industrialize, indicating the great potential in practical applications. [ABSTRACT FROM AUTHOR]