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The nanofiltration (NF) membrane has not been extensively competent for rejection of monovalent ions (such as Cl− and NO3−), and the strategy for enhancing monovalent ion rejection and permeation flux still faces a significant challenge. Herein, based on our previous polyethersulfone (PES)‐type NF membrane (NF‐0), two novel NF membranes were fabricated with additional incorporations of 2,2′‐benzidinedisulfonic acid (BDSA) and forward osmotic extraction solution‐functioned nanoparticles (MNPs) to remove nitrate from the aqueous solution. The fabricated NF‐BDSA membrane with introduction of BDSA in ultrathin layer displays a significant nitrate rejection of 92.2% and an acceptable permeation flux of 21 L m−1 h−1 at 0.6 MPa. As anticipated, the obtained NF‐MNPs1.0 membrane with additional incorporation of MNPs (1.0 wt% addition) in the substrate layer of NF‐BDSA membrane achieves further improvements in nitrate rejection (95%) and water permeability (32.3 L m−1 h−1); encouragingly, this membrane exhibits comparable monovalent ion rejection and permeation flux to reverse osmosis membrane under relatively low pressure. Compared with those of NF‐0 membrane, the permeation flux and nitrate rejection of NF‐MNPs1.0 membrane increase by 111.1% and 6.1%, respectively. Moreover, the superior performances of endurance, antifouling and chlorine resistance of NF‐MNPs1.0 membrane demonstrate its expectable perspective of potential engineering applications. [ABSTRACT FROM AUTHOR]

A range of new fluorine‐containing copolyarylates were successfully produced through interfacial polymerization using hexafluorobisphenol A (BPAF) featuring a symmetric trifluoromethyl group structure, bisphenol B (BPB), and two acyl chloride monomers as raw materials. The results indicated that the synthesized amorphous copolyarylates exhibited good solubility, with number average molecular weights (Mn) of 19,000–44,000 g/mol, weight average molecular weights (Mw) of 66,000–159,000 g/mol, and intrinsic viscosities of 0.66–1.19 dL/g. The thermal stability of copolyarylates increased with the increase of BPAF monomer content (0~100%), which was manifested by the linear increase of glass transition temperature (Tg) from 201.6 to 237.1°C, and the increase of 5% thermogravimetric weight loss temperature (T5%) from 474.1 to 491.5°C. The tensile strength of copolyarylates ranged from 52.63 to 59.93 MPa, the tensile modulus ranged from 1102.08 to 1502.84 MPa, and the elongation at break ranged from 32.0 to 75.5%. In addition, the copolyarylates had good dielectric properties with a dielectric constant of 2.58–3.75 at 107 Hz and a dielectric loss tangent of 0.021–0.028. [ABSTRACT FROM AUTHOR]

Polyethylene‐supported nanofiltration (NF) membranes have been reported for several cases in recent years. However, few have disclosed a NF membrane which achieves a high salt/water separation efficiency. Here, a novel polyamide NF membrane was prepared by conducting interfacial polymerization on poly(vinyl alcohol)‐decorated polyethylene separator. The polyethylene‐supported NF membranes were systematically investigated with respect to chemical structures, microscopic morphology, surface properties, as well as desalination performance. In particular, a distinctive morphology transformation occurred on the polyamide layers through regulating poly(vinyl alcohol) loading amounts. Performance testings demonstrated the optimal membrane reaches a water permeance over 17.4 L·m−2·h−1·bar−1 and Na2SO4 rejection above 98.7%, as well as favorable performance stability. This work may provide some consideration for fabricating NF membranes with new support layers and good desalination performance. [ABSTRACT FROM AUTHOR]

A rapid and mild coating strategy was applied on the millimeter scale calcium alginate capsules (Ca‐SA caps) by in situ interfacial polymerization of ethyl cyanoacrylate (ECA). The generated poly(ethyl cyanoacrylate) (PECA) coating was initiated by trace water in the surface of the Ca‐SA caps. The effects of ECA content, reaction time, and type of aromatic solvent on the morphology and control‐release property of the resulting PECA‐coated Ca‐SA caps (Ca‐SA caps@PECA) were investigated. The results demonstrated a white PECA layer successfully coated on the surface of Ca‐SA caps. Notably, the Ca‐SA caps@PECA remained consistently pleasing spherical shape as prepared in methylbenzene and ethylbenzene. When the ECA was 6 mL, the thickness of PECA layer of the Ca‐SA caps@PECA was 43.52 μm. Compared with the Ca‐SA caps, the weight retention ratio of water in the Ca‐SA caps@PECA increased by 254.61%, indicating the effective delay of water diffusion from core of the Ca‐SA caps@PECA. Moreover, the PECA coating improved the stability of the Ca‐SA caps@PECA, which achieved release‐controlling of dye at different pH. This method provides solution for surface modification of fragile hydrogel capsules to effectively control the releasing of liquid core, which is highly valuable in the field of food, cosmetic, and medical delivery. [ABSTRACT FROM AUTHOR]

In this study, paper coated with a polyamide film containing a molecularly imprinted polymer (MIP) of benzalkonium chloride (BKC) is prepared. Its BKC adsorption ability and selectivity for BKC adsorption are investigated. The MIP is prepared by agitating an ethylenediamine solution containing an azo initiator, BKC as a template material, and methacrylic acid (MAA) as the functional monomer. First, filter paper soaked in this mixture is impregnated with a cyclohexane solution of terephthaloyl chloride and a BKC–MAA–MIP‐containing polyamide film is prepared on the surface of the paper. Paper containing BKC–MAA–MIP adsorbs BKC. The paper with the highest BKC removal efficiency is prepared under the following conditions: 4 mL MAA functional monomer, 2.5 w/v% ethylenediamine, and 10 min MIP synthesis time. The paper with BKC–MAA–MIP selectively adsorbs BKC from a solution containing BKC, tetracycline hydrochloride, and caffeine. Thus, a polyamide film containing BKC‐MAA‐MIP formed on paper can effectively and selectively remove BKC from aqueous environments. [ABSTRACT FROM AUTHOR]

Spiropyran photochromic materials have been widely studied in military camouflage, optical data storage, information encryption, and fashion ornaments. The non‐photochromism and low endurance of solid spiropyran make the challenges of their application. Photochromic microcapsules with a butyl acetate solution of spiropyran as core and polyurethane as shell are synthesized via interfacial polymerization. The optimized polyurethane photochromic microcapsules are prepared with a Tween 20 concentration of 4 wt%, core–shell ratio of 16:5, and spiropyran concentration of 0.40 wt%. Polyurethane photochromic microcapsules with a mean particle diameter of 0.33 μm are obtained. The morphology shows smooth spheres, and the core–shell structure is observed. Butyl acetate in the microcapsule core does not evaporate at a temperature lower than 218.01°C as the microcapsule shell insulates heat. The polyurethane photochromic microcapsules are mixed with adhesive, thickener, and water into a paste and screen‐printed on cotton fabric. The printed fabric shows the ΔE of 17.56, 11.93, and 6.96 after 80s irradiation with the xenon lamp intensity of 102, 68, and 34 mW cm−2. The light stability of the photochromic fabric is excellent as ΔE decreases about 8.28% after 20 cycles of UV‐Vis irradiation. [ABSTRACT FROM AUTHOR]

Based on the solution‐diffusion model of pervaporation (PV) technique, the development of thin‐film composite membranes (TFC) with a highly hydrophilic surface and hydrophobic internal structure is more conducive to the rapid adsorption and desorption of water molecules to overcome the trade‐off effect between flux and separation selectivity. Herein, the polyamide PV membrane was fabricated via interfacial polymerization (IP) with trimesoyl chloride (TMC) and polyethylenimine (PEI) as organic and aqueous phase monomer, respectively, on the hydrolyzed polyacrylonitrile (HPAN) substrate. Subsequently, the hydrophilic modification layer was prepared via sodium alginate (SA) crosslinking with Ca2+ to form the egg‐box network. The results indicated the optimized TFC membrane exhibited high separation factor of 525.1 with desirable permeation flux of 2083.9 g m−2 h−1 for the pervaporation dehydration 85 wt% ethanol/water solution at 70°C. The modification method of hydrophilic surface opens up new avenues for the preparation of PV membrane with high separation performance and low‐cost. [ABSTRACT FROM AUTHOR]

A series of polyarylates composed of different bisphenol monomers were synthesized by interfacial polymerization using 9,9‐bis(4‐hydroxyphenyl)fluorene (BHPF), 2,2‐bis(4‐hydroxyphenyl)butane (BPB), terephthaloyl chloride (TPC), and isophthaloyl chloride (IPC) as raw materials. The DFT calculations showed that the energy required for the reaction of BHPF with TPC/IPC was between 15.82 and 16.04 Kcal/mol, which was higher than the energy required for the reaction of BPB with TPC/IPC of 8.05–8.40 Kcal/mol. The solubility test showed that the solubility of BHPF‐BPB‐type polyarylate was better than that of BPB‐type polyarylate in various organic solvents with Tg ranging from 199.3 to 215.0°C, indicating that the solubility was improved while increasing the Tg of the products. The weight loss (T5%) and maximum weight loss (Tmax) of BHPF‐BPB‐type polyarylates under N2 atmosphere ranged from 464.6–489.4°C and 521.7–534.6°C, indicating good thermal stability. The tensile strength of the BHPF‐BPB‐type polyarylates ranged from 53.21 to 61.23 MPa, Young's modulus ranged from 1479.66 to 1867.23 MPa and elongation at break ranged from 19.5% to 30.1%. The mechanical property test showed that the BHPF‐BPB‐type polyarylates have high tensile strength. These characteristics indicate that BHPF‐BPB‐type polyarylates have a very broad potential for application in engineering plastics. [ABSTRACT FROM AUTHOR]

High concentrations of fluoride in drinking water can lead to fluorosis of teeth and bones and other serious diseases, while nanofiltration is an attractive technique for fluoride removal. Interfacial temperature can determine the monomer diffusion rate in interfacial polymerization (IP) process, thereby tuning the structure of membrane such as thickness, pore size and surface charge. Herein, a fully‐aromatic polyamide nanofiltration membrane with desirable separation performance was customized by interface temperature. The resulting membrane exhibits a flux of 6 L m−2 h−1 bar−1 and the molecular weight cut‐off is 211 Da, most importantly, a 90.3% F− rejection to underground water, indicating that the membrane has application potential in underground water treatment. This work helps to better understand the effects of interface temperature on the IP process and provides a new strategy to address the drinking water problem. [ABSTRACT FROM AUTHOR]

The proper control of polymerization is a prerequisite in fabrication of thin film composite reverse osmosis (RO) membranes. But it not trivial when hydrophilic substrates are used. Herein, we report an innovative approach which involves using an aromatic/aliphatic solvent mixture of toluene and n‐hexane as the organic phase for interfacial polymerization. Membranes were tuned by using a customized developed polyacrylonitrile (PAN) substrate and exploring the impacts of organic solvent and curing temperatures on their morphology and performance characteristics. Results revealed that increasing the temperature of organic phase to 20°C improved salt rejection significantly to 98.6% with the flux of 16.1 LMH. However, its further increase to 30°C was not beneficial due to formation of a looser chain packing which led to rejection drop. In addition, raising curing temperature to 90°C was not favorable due to transformation of surface morphology from ridge‐and‐valley to nodular structure, accompanied with defective sites at the selective layer and insufficient degree of crosslinking evidenced by declines in both flux and rejection to 11.1 LMH and 83.4%, respectively. Overall, the findings suggested that an optimal performance could be obtained by using a solvent mixture of toluene/n‐hexane (1,1) and setting organic solvent and curing temperatures to 20 and 70°C, respectively. [ABSTRACT FROM AUTHOR]

Nanoaggregates made from amino acid‐based polymers have been an important platform for targeted drug delivery systems such as the lungs. Therefore, the aim of the present study is to develop tyrosine‐based poly(ester amide)s (Tyr‐PEA) for dry powder inhaler (DPI) of a potent drug (fluticasone propionate [FP]) using interfacial polymerization. The molecular and surface profiling characteristics were evaluated using Fourier‐transformed infrared spectroscopy, X‐ray diffraction, transmission electron microscopy, particle size analysis, nuclear magnetic resonance, differential scanning calorimetry, and scanning electron micrographs. The aerodynamic performance was evaluated using the NGI. The results confirmed the formation of the PEA and FP‐loaded Tyr‐PEA with an average particle size of, 45.39 ± 6.32 nm. The produced FP/Tyr‐PEA showed entrapment efficiency and encapsulation capacity of FP of 92.32% and 0.526% respectively, which enabled the delivery of this potent drug in a reasonable dose. The in‐vitro performance of the FP‐loaded PEA was compared to a marketed product and results revealed a significant enhancement of the emitted dose (87.29% vs. 59% respectively [t‐test, p < 0.05]). FP‐loaded Tyr‐PEA produced a higher respirable dose when compared to the marketed FP DPI (48.63 μg vs. 34.15 μg). Overall, FP‐loaded Tyr‐PEA was successfully prepared with optimal performance. Tyr‐PEA‐based nanoparticles provide a potential platform for targeted drug delivery, particularly potent actives. [ABSTRACT FROM AUTHOR]

Polyamide‐based thin film nanocomposite (TFN) membranes were prepared by incorporating nanoparticles in an aqueous phase containing m‐phenylenediamine (MPD) and an organic phase containing trimesoyl chloride (TMC) by interfacial polymerization (IP) method. The 3‐aminopropyltrimethoxy silane grafted mesoporous synthetic hectorite (APTMSH) was synthesized and added in an aqueous monomer solution while the IP. In this work, the TFN layer interfacial compatibility has been enhanced by building the covalent bond between APTMSH and other two monomers by IP method. The coating of the TFN selective layer was done on the inner surface of polysulfone hollow fiber membranes. The interesting results were obtained for the binary mixture gas separation containing water vapor/N2 and CO2/CH4. Improved gas permeance and selectivity have been obtained using APTMSH‐incorporated TFN membranes. The developed TFN membranes have been characterized using several physicochemical methods. The results show that with the addition of APTMSH in MPD solution up to 0.5 w/w% the best water vapor permeance 2485 GPU and CO2 permeance 22.3 GPU were obtained along with water vapor/N2 selectivity 725.5 and CO2/CH4 selectivity 26.68 respectively through APTMSH@TFN‐3 membrane. [ABSTRACT FROM AUTHOR]

One process involved in biorefinery for generation of value‐added products is fermentation. After fermentation, the downstream bioproduct purification process is conventionally performed by organic solvent extraction, which is environmentally‐hazardous and costly. Membrane‐based separation is a cost‐efficient and environmentally‐benign method for bioproduct separation and purification. In this study, a thin film composite (TFC) nanofiltration (NF) membrane was prepared and the pore size and charge of the polyamide layer were controlled by introducing iminodiacetic acid (IDA), a charged monoamine monomer, with piperazine (PIP) during interfacial polymerization (IP). The newly‐developed NF membrane was found to have a molecular weight cut‐off (MWCO) of 500 to 1350 Da, allowing the permeation of the fermentation product, while rejecting other higher molecular weight compounds. IDA addition in the aqueous amine solution during IP effectively engineered the MWCO values and pore sizes of TFC NF membranes for specific applications, such as separation of fermentation bioproducts. This study successfully showed that IDA reduced the diffusivity of PIP during IP, which negatively affected the polyamide formation and membrane performance. The optimal PIP:IDA concentration ratio was determined by MWCO and effective pore diameter for effective bioproduct separation and purification, which could not be performed by the current commercially‐available NF membranes. [ABSTRACT FROM AUTHOR]

As the main water treatment material, polymeric membranes inevitably suffer from membrane fouling. In this work, novel lignin‐based polyester composite nanofiltration membranes (NFM) with ethanol and chlorine resistance were fabricated via interfacial polymerization. Lignin alkali (LA), a green lignin derivative, typically treated as chemical waste in the paper industry, was employed as the aqueous monomer, trimesoyl chloride (TMC) is served as the organic monomer. The structure and separation properties of the lignin‐based NFM were studied, revealing that the dense polyester separation layer may show good performance for dye removal. The rejections of the optimized LA/TMC‐3 membrane with an excellent permeation flux of 13.9 kg m−2∙h−1 for rose Bengal sodium salt, brilliant blue, congo red, rhodamine B, MgSO4, and NaCl are 97.6%, 97.3%, 97.8%, 71.34%, 51.4%, and 31.8%, respectively. Moreover, the LA/TMC‐3 membrane also shows long‐term tolerance in ethanol and sodium hypochlorite solution; the rejection of LA/TMC‐3 to dye only decreases 8% after 8 days when immersed in alcohol, while the normalized rejection maintains 94% after 4000 ppm‐hours of continuous exposure to chlorine. This lignin‐based polyester membrane may broaden the sustainable utilization sphere of lignin derivatives, at that provide a referable direction for the development of membrane materials. [ABSTRACT FROM AUTHOR]

Efficient separation of aromatic‐aliphatic hydrocarbon mixtures has long been an important topic in chemical industries. Organic nanofiltration (OSN) has been revealing great promise in separating solvent mixtures that has not been effectively resolved by the state‐of‐the‐art technologies. Herein, novel OSN membranes are designed for the separation of toluene and n‐heptane. Polyamide active layer with diaminonaphthalene as the aqueous phase monomer is prepared by interfacial polymerization for the first time. The addition of polydimethylsiloxane gutter layer, as well as the combination of spin coating technique and macroporous substrate, renders the membranes with loose and defect‐free architectures. The as‐designed membranes achieve a rather high selectivity of toluene over n‐heptane (>4) together with ultra‐high toluene permeance (>180 L m−2 h−1 bar−1). These membranes also present excellent stability in the long‐term operation. [ABSTRACT FROM AUTHOR]

ABSTRACT A facile interfacial synthesis strategy is proposed to synthesize self-assembled polypyrrole (PPy) free-standing films for electrochemical capacitors with the assistance of surfactants. The chemical structure of the obtained samples is characterized by Fourier transform infrared. The morphologies of the samples are studied by scanning electron microscope. The results show that the prepared PPy films own highly porous structures using Tween80 as a surfactant, while the synthesized PPy films have vesicular structures by adding Span80 as a surfactant. Furthermore, lowering polymerization temperature makes PPy films have smaller and more pores or vesicles. The PPy films prepared at 0°C with Tween80 as a surfactant possess a high specific capacitance of 261 F g−1 at 25 mV s−1 as well as retain 75% of the initial specific capacitance value after 1000 cycles. The good electrochemical properties can be attributed to the highly porous structural advantage of the PPy films caused by Tween80. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41615. [ABSTRACT FROM AUTHOR]

The layer-by-layer (LbL) self assembly deposition technique was used to prepare multilayer thin films of anionic polyaniline-blend-poly(sodium 4-styrenesulfonate) (PANI-PSS) and cationic poly(diallydimethylammonium chloride) (PDADMAC). Anionic polyaniline was prepared by the interfacial polymerization of aniline monomer in the presence of PSS which acted as template to provide water solubility. The PSS to PANI concentration ratios used in the synthesis step was found to have a major effect on the final PANI-PSS synthesis, its self assembly and the electrical properties of the prepared films. The optical and electrical properties of the films were measured by ultraviolet-visible spectroscopy (UV-Vis) and a 4-point probe setup, respectively while the thickness of the films was measured by atomic force microscopy (AFM). Results showed that the optimum condition for the film growth and optimal conductivity were obtained with different synthesis conditions. These results suggest that the PSS concentration used for interfacial synthesis of PANI must be finely tuned depending on the type of application aimed by the user. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

A novel polyamide-paraffin microencapsulated phase change material (MEPCM) was prepared by interfacial polymerization technique using 1,3,5-benzenetricarbonyl chloride (TMC) and ethylenediamine as monomers and 30# paraffin as core material. Morphology, chemical composition, thermal properties of the MEPCM were studied by scanning electron micrograph, FT-IR spectrum, differential scanning calorimeter analysis and thermogravimetric analysis. The solvent resistances of the MEPCM were also studied by observing the morphology changes of the MEPCM under optical microscope. Results indicate that the MEPCMs prepared under optimal conditions have spherical shape with average diameter of 6.4 µm, and the polyamide shell has successfully packaged the paraffin core. The MEPCM has a high efficiency in storing and releasing heat. The latent heat is 121.7 J/g and the microencapsulation ratio is 87%, 5% weight loss temperature is 260°C. The MEPCM is stable in H2SO4 solution (ω = 0.98), NaOH solution (ω = 0.40), ethanol, acetone, ether, dimethylformamide while can be destroyed by ZnCl2 solution (ω = 0.60). © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci, 2013 [ABSTRACT FROM AUTHOR]

Double-shell microcapsules containing butyl stearate were prepared through interfacial polymerization. The outer shell is polyurea formed through polymerization of toluene-2,4-diisocyanate (TDI) and diethylene triamine, and the inner shell is polyurethane (PU) formed through polymerization of TDI and polypropylene glycol 2000 (PPG2000). Styrene maleic anhydride copolymer was used as emulsifier. The effects of core to monomer ratio and dosage of PPG2000 on core content and encapsulation efficiency of microcapsules were investigated. The core content has a maximum at core to monomer ratio of 3-4, and the encapsulation efficiency has a maximum value of 95% at core to monomer ratio of 2. The prepared microcapsules were smooth and compact and have an obvious latent heat of 85 J/g. The shell structure of microcapsules was polyurea and PU. The average diameter of the microcapsules was 1-5 μm. The stabilities of the double-shell microcapsule, such as anti-ethanol wash and antiheat properties are obviously improved than those of single-shell microcapsule. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

A series of novel fluorinated aromatic polyesters containing trifluoromethylphenoxy pendant groups was synthesized by interfacial polycondensation of 2-(4-trifluoromethylphenoxy)terephthalyl chloride with various bisphenols in dichloromethane. The polyesters obtained in good yields had weight-average molecular weights of 70,600-29,800 g/mol, polydispersities of 1.81-2.08, and were all amorphous. All polyesters were easily soluble in organic solvents such as N,N-dimethylformamide, tetrahydrofuran, o-chlorophenol, pyridine, and dichloromethane. These fluorinated polyesters showed glass transition temperature of 133-210°C, and good thermal stability with almost no weight loss up to 378°C, the 10% weight loss temperature of 472-523°C as well as char yield of 32-63% at 600°C in nitrogen. These polyester films cast from chloroform solutions exhibited tensile strengths ranging from 102 to 126 MPa, elongation at break from 6.3% to 11.7%, and tensile moduli from 2.1 to 3.3 GPa. The resulting polyester films also displayed low dielectric constants between 2.18 and 2.49 (1 MHz), high transparency with an ultraviolet-visible absorption cut-off wavelengths in the 332-355 nm range, and excellent electric strengths (50.4-65.6 kV/mm) and volume resistivity (2.51-6.03 × 1016 Ω cm). © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

In this study, we prepared monosultap microcapsules in an inverse emulsion through interfacial polymerization for the first time. The microcapsules are spherical pellets with intact and smooth shell and have a narrow particle size distribution with an average size of about 2.35 μm. More importantly, our microcapsules have excellent thermal stability with a starting decomposition temperature of 233.1 °C, high encapsulation efficiency of 81.9% as well as long‐term slow release of monosultap under different conditions. In addition, the shell of the microcapsules can degrade completely in the natural condition, avoiding the pollution to the environment. It can be believed that our microcapsules will show good service performance if employed in agricultural industry. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48594. [ABSTRACT FROM AUTHOR]