Optimization of sulfonated polyethyleneimine zwitterionic coating mediated by polydopamine for poly(vinyl chloride) antifouling

Although poly(vinyl chloride) (PVC) has been widely used as blood-contacting materials in extracorporeal circuits and indwelling medical devices, its hydrophobicity also is a limitation due to the adsorption of plasma proteins and the immediately followed thrombosis cascade and bacterial infections. Herein, we developed a mild and simple strategy for improving the hydrophilicity and antifouling properties of the surface via mussel-inspired chemistry. Different amounts of 1,3-Propanesultone (1,3-PS) were attached onto the polyethyleneimine (PEI), so as to modify it into the zwitterion, called PES_X. Two layer-by-layer approaches about PES_X grafting on PVC substrates were designed. One strategy was by coating PES_X after coating polydopamine (PDA) on PVC surface, obtaining PDA-PES_X coatings. The other was by grafting PES_X after co-deposition treatment of PDA and PES_X with appropriate feeding ratio on PVC, obtaining PDA/PES_X-PES_X coatings. The study results indicated that the PDA/PES_0.5-PES_0.5 coatings with optimized PEI molecular weight and sulfonation degree, presented about 2.5–3 times reduction in BSA adsorption (0.77 μg/cm²) compared with PDA/PES_0.5 (1.93 μg/cm²) and PDA-PES_0.5 (2.26 μg/cm²), and kept long time antifouling stability. Moreover, the more excellent antifouling performance of PDA/PES_0.5-PES_0.5 was also seen on fibrinogen (Fg), γ-globulin (γ-GL), and the mixture of these proteins. Meanwhile, PDA/PES_0.5-PES_0.5 could prevent the adhesion of blood components and bacteria on the surface as well as maintain excellent hemocompatibility and cytocompatibility. We had hopes that our simple and mild strategy will find practical application in surface engineering of clinical use in blood-contacting medical devices.     

Hemocompatible biomaterials of zwitterionic sulfobetaine hydrogels regulated with pH-responsive DMAEMA random sequences

Polyzwitterionic biomaterial with pH-responsive and hemocompatible dual functions is formulated by the copolymerization of 2-(N, N-dimethyl amino) ethyl methacrylate (DMAEMA) sequences and sulfobetaine methacrylate (SBMA) moieties. Hydrogels are salt responsive, due to the interplay between hydrogen bonds formation, ions solvation, and antipolyelectrolyte effect, while DMAEMA sequences provide pH-responsiveness. Their low-fouling nature is demonstrated using plasma proteins and bacteria. Improved hemocompatibility with SBMA content is unveiled by the resistance to platelet and erythrocyte attachment, as well as from delayed plasma clotting time. Overall, this study suggests that dual-functional zwitterionic hydrogels are promising pH-responsive and hemocompatible polymeric biomaterials.     

Interpolymer associations between poly(vinyl alcohol) and poly(diallyldimethylammonium chloride) in aqueous dilute solution

This article studied the compatibility of poly(vinyl alcohol) (PVA) with poly(diallyldimethylammonium chloride) (PDADMACl) in a dilute aqueous solution. At a total mixture concentration and a constant molecular weight of PDADMACl, it was found that interpolymer associations increase with the molecular weight and decrease with the degree of hydrolysis of the PVA sample (87–89 and 98–99%). From these results, it can be deduced that the compatibility of PVA and PDADMACl is due to specific intermolecular interactions that could be assigned mainly to electrostatic interactions between hydroxyl groups within PVA chains and ion atoms within PDADMACl. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 433–435, 2002     

Electrospinning fabrication and characterization of poly(vinyl alcohol)/waterborne polyurethane nanofiber membranes in aqueous solution

Poly(vinyl alcohol) (PVA)/waterborne polyurethane (WBPU) nanofiber mats were prepared using electrospinning method with aqueous solutions. Scanning electron microscopy (SEM), X‐ray diffraction (XRD), thermal gravimetric analyzer (TGA), and tensile strength testing machine (ZWICK) were used to characterize the morphology and properties of the PVA/WBPU nanofiber mats. The results showed that the morphologies of PVA/WBPU nanofiber mats changed with the total solid concentration and the mass ratio of PVA/WBPU in the spinning solution. The tensile strength and thermal stability of the fibers could be significantly affected by the WBPU contents. The electrospun PVA/WBPU membranes showed higher water uptake, which would have potential applications in wound dressings. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

稀乙酸对聚乙烯醇水溶液静电纺丝性能的影响

采用质量分数3%乙酸水溶液作为高醇解度聚乙烯醇(PVA)的溶剂,研究了PVA稀乙酸溶液的性质及其静电纺丝工艺。结果表明:加入质量分数3%乙酸,PVA溶液粘度下降,表面张力及电导率提高;纺丝液浓度对PVA稀乙酸溶液的静电纺丝性能影响最大;当PVA稀乙酸溶液质量分数为8%～13%,固化距离15mm,纺丝电压14～18kV时,可制得形态良好的PVA超细纤维无纺毡。     

Investigation of the interpolymer association between poly(vinyl alcohol) and poly(sodium styrene sulfonate) in aqueous solution

A viscosimetric method has been used to study the interpolymer association between poly(vinyl alcohol) (PVA) and poly(sodium styrene sulfonate) (PSSNa) in aqueous solution. At constant molecular weight of PSSNa, it was found that, the PVA and PSSNa associations were improved with the decrease of molecular weight of PVA and the decrease of its hydrolysis degree. The measurement of intrinsic viscosity [η] and the determination of Huggins associative coefficient K_H of different PVA samples were used to select the most appropriate PVA sample, which leads to homogeneous polymer–polymer mixtures (PVA with hydrolysis degree 87–89%, molecular weight 124,000–186,000 g/mol, intrinsic viscosity [η] = 1.02 dL/g, and Huggins associative coefficient K_h.ass = 0.76). The obtained results show that the interpolymer association between PVA and PSSNa, in aqueous solution, is mainly due to intermolecular hydrogen bonds between hydroxyl groups of PVA and sulfonate groups of PSSNa. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Separation of aqueous organic liquid solutions through polymer membranes

Characteristics of permeation and separation for aqueous dimethyl sulfoxide, acetic acid and ethanol solutions through some polymer membranes such as chitosan, poly(vinyl chloride) and poly(dimethyl siloxane) membrane were studied by evapomeation. In temperature difference controlling evapomeation (TDEV), when the temperature of the feed solution was kept constant and the temperature of the membrane surroundings was changed, permselectivity for water increased in the chitosan and poly(vinyl chloride) membranes; in the poly(dimethyl siloxane) membrane the perm-selectivity for ethanol increased while decreasing the temperature of the membrane surroundings. Permeation and separation mechanisms for aqueous organic liquid solutions through the above polymer membranes by the TDEV method are discussed.     

Poly(sulfobetaine)s and corresponding cationic polymers. X. Viscous properties of zwitterionic poly(sulfobetaine) derived from styrene–(N,N‐dimethylaminopropyl maleamidic acid) copolymer in aqueous salt solutions

A styrene–[N,N‐dimethyl (maleamidic acid) propyl ammonium propane sulfonate] (SDMMAAPS) copolymer was synthesized through an amidoacidation reaction of styrene–maleic anhydride (SMA) alternating copolymer with N,N‐dimethylaminopropylamine (ring‐opening reaction), which was then reacted with propane sultone. The effect of various salt solutions on the intrinsic viscosity of this ampholytic ADMMAAPS copolymer was investigated. The results showed that the effect of counter ions on the intrinsic viscosity of SDMMAAPS was not entirely similar to that of other zwitterionic poly(sulfobetaine)s. The greatest difference from other poly(sulfobetaine)s is the carboxylic group on the polymer chain unit of SDMMAAPS. The Huggins constants for SDMMAAPS in aqueous salt solutions, however, were also quite different from those of other sulfobetaine copolymers, such as styrene–N,N‐dimethyl (maleimido propyl) ammonium propane sulfonate] (SDMMAPS) copolymer. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 726–734, 2004     

Graft copolymerization of methyl acrylate onto poly(vinyl alcohol) initiated by potassium diperiodatoargentate(III)

The graft copolymerization of methyl acrylate onto poly(vinyl alcohol) (PVA) using potassium diperiodatoargentate(III) [Ag(III)]–PVA redox system as initiator was studied in an alkaline medium. Some structural features and properties of the graft copolymer were confirmed by Fourier‐transfer infrared spectroscopy, scanning electron microscope, X‐ray diffraction and thermogravimetric analysis. The grafting parameters were determined as a function of concentrations of monomer, initiator, macromolecular backbone (X?_n = 1750, M? = 80 000 g mol^?1), reaction temperature and reaction time. A mechanism based on two single‐electron transfer steps is proposed to explain the formation of radicals and the initiation profile. Other acrylate monomers, such as methyl methacrylate, ethyl acrylate and n‐butyl acrylate, were also used to produce graft copolymerizations. It has been confirmed that grafting occurred to some degree. Thermogravimetric analysis was performed in a study of the moisture resistance of the graft copolymer. Copyright © 2004 Society of Chemical Industry     

Preparation of high-performance reverse osmosis membrane by zwitterionic polymer coating in a facile one-step way

Aiming at preparing high-performance polyamide (PA) reverse osmosis (RO) membrane in a facile and high effective way, the codeposition strategy of dopamine and zwitterionic polymer was first applied to modify PA RO membrane. The noncovalent bonds between dopamine and Poly [2-(Methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (PSPE) act to fix PSPE onto the membrane surface and simultaneously destroy the interaction force between dopamine aggregations so that the modified layer could equably form on the PA layer. PSPE significantly improved the hydrophilicity [the water contact angle (WCA) of S-D-3 is 25.3°] of the modified membrane. And, the smoother surface was noticed on the modified membrane. All of these endow the PSPE/dopamine modified membrane superb water flux (the maximum water flux is 51.86 L m⁻¹ h⁻¹ at 1.6 MPa and 25 °C) and impressive antifouling and anti-adhesion properties to bovine serum albumin (BSA) (protein), sodium dodecyl sulfate (anionic surfactant), and dodecyl trimethyl ammonium bromide (cationic surfactant) with salt retention was well maintained. Notably, in the BSA fouling test, nearly 100% of the flux recovery ratio was achieved. This method is promising to be employed in industrial scale-up production. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48355.     

Evaluating The Extent of Bio-Polyester Polymerization in Solid Wood by Thermogravimetric Analysis

In this study, the thermogravimetric analysis (TGA) technique has been applied to determine the extent of in situ polymerization achievable in solid wood on treating with bio-polyester oligomers. Low-molecular-weight oligomers of poly(lactic acid) (PLA), poly(glycolic acid) (PGA), poly(butylene succinate) (PBS), and poly(butylene adipate) (PBA) were impregnated and then thermally polymerized within solid wood to enhance the physical properties of wood. TGA revealed a similar degree of oligomer polymerization was achieved either with pure oligomers or within the wood structure. The influence of relatively acidic treatments, such as low-molecular-weight PGA oligomers, was observed to lead to degradation of the hemicellulose wood component. Polymerization of PLA and PGA oligomer treatments which penetrate the wood cell wall gave relatively lower wood thermal stability. Treatment and polymerization of lumen filling PBS and PBA oligomers contributed to increased wood thermal stability.     

Synthesis of copolymers from 3,5-dioxo-4,10-dioxatricyclo-[5.2.02,6]dec-8-ene and vinyl monomers by photopolymerization and their biological activities

Photocopolymerizations of 3,5-dioxo-4,10-dioxatricyclo[5.2.0^2,6]dec-8-ene (DDTD) with methacrylic acid (MA) acrylamide (AAm) and vinyl pyrrolidone (VP) were carried out in 2-butanone using dimethoxy benzoin (DMB) as an initiator at 25°C. The structures of the polymers obtained from photopolymerizations of corresponding monomer pairs were confirmed to be poly(DDTD-co-MA), poly(DDTD-co-AAm) and poly(DDTD-co-VP) by ¹H NMR and ¹³C NMR spectroscopies, and the average molecular weights were determined by gel permeation chromatography (GPC). The weight average molecular weights (M_w) of the polymers were in the range 9500–17300. The polymers were soluble in water, dimethyl sulphoxide (DMSO) and dimethyl formamide (DMF). The contents of DDTD units in the copolymers were 19, 37 and 45%. The in vitro cytotoxicities of the polymers were evaluated using mouse mammary carcinoma (FM-3A), mouse leukaemia (P-388) and human histiocytic lymphoma (U-937) cell lines. The in vivo antitumour activities of the polymers were estimated by the survival time of sarcoma 180 tumour-bearing mice. The in vivo antitumour activities of the polymers were greater than those of 5-fluorouracil (5-FU) and monomeric DDTD at a dose of 0·8mgkg^-1. Poly(DDTD-co-AAm) and poly(DDTD-co-VP) showed higher antitumour activity than 5-FU and monomeric DDTD at all doses tested. © 1998 SCI.     

Dispersion polymerization of styrene in aqueous alcohol solution: Effects of reaction parameters on the polymer particle formation

Dispersion polymerization of styrene in an aqueous alcohol solution using poly(2-ethyl-2-oxazoline) as a polymeric stabilizer was performed to prepare micron-size monodisperse polystyrene particles. As the water content of the solvent increased, the polymerization rate and the molecular weight of the polymer particles increased and the particle size decreased. Effects of concentrations of stabilizer and initiator upon the polymerization and the size of the resulting polystyrene particles have been examined in the solvent containing different water contents.     

低聚合度、低醇解度聚乙烯醇的合成与性能研究——I.低聚合度聚醋酸乙烯酯的合成

以甲醇为溶剂,偶氮二异丁腈(AIBN)为引发剂,采用自由基聚合方法合成了低聚合度聚醋酸乙烯酯,并对其结构进行了表征。讨论了聚合时间、引发剂用量、物料配比、聚合温度等因素对聚合率的影响,获得了相对较佳的工艺参数。     

Physical Properties of Plasticized Poly(vinyl chloride) Blended with Poly(methyl methacrylate) Nanoparticles Synthesized by Differential Microemulsion Polymerization

In this work, poly(methyl methacrylate) (PMMA) nanoparticles synthesized by differential micro emulsion polymerization were used to improve the physical properties of plasticized poly(vinyl chloride) (PVC). PVC, plasticizer (40 phr), heat stabilizer (2 phr), and lubricant (0.2 phr) were melt-mixed with varied amount of the PMMA nanoparticles (3, 5, 7, and 9 phr) on a two-roll mill, followed by compression molding. The results showed that the tensile strength, Young's modulus, tear strength, and thermal stability were improved, but the elongation at break deteriorated with increased PMMA content. Moreover, the flammability of the plasticized PVC was not improved by the PMMA nanoparticles.     

Iodination of plasticized poly(vinyl chloride) in aqueous media via phase transfer catalysis

Nucleophilic substitution of chlorine on plasticized poly(vinyl chloride) (PVC) was carried out using potassium iodide (KI) in the presence of a phase transfer catalyst (PTC) in aqueous media. Iodination was confirmed using energy dispersive X‐ray analysis (EDAX). The extent of iodination was studied with respect to time, temperature, concentration of the reactants, as well as different PTCs. Among the different PTCs examined, tetrabutylammonium bromide (TBAB) and tetrabutylammonium hydrogen sulfate (TBAH) were found to be highly efficient for the reaction. About 25% increase in weight was observed for PVC sheets iodinated under optimal reaction conditions. The thermal stability of the modified PVC was found to be impaired upon iodination. The iodinated PVC released iodide ions when kept in distilled water, as evidenced by UV spectroscopy. Sustained release of iodide ion in distilled water was followed up for about 30 days. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 493–499, 2002; DOI 10.1002/app.10176     

Kinetics of graft copolymerization of poly(hexanedioic acid ethylene glycol) and methyl acrylate initiated by potassium diperiodatocuprate(III)

A redox system, potassium diperiodatocuprate(III) [DPC]/poly(hexanedioic acid ethylene glycol) (PEA) system, was employed to initiate graft copolymers of methyl acrylate (MA) and PEA in alkaline medium. The results indicate that the equation of the polymerization rate (R_p) is as follows: R_p = k [MA]^1.62[Cu(III)]^0.69, and that the overall activation energy of graft polymerization is 42.5 kJ/mol. The total conversion at different conditions (concentration of reactants, temperature, concentration of the DPC, and reaction time) was also investigated. The infrared spectra proved that the graft copolymers were synthesized successfully. Some basic properties of the graft copolymer were studied by instrumental analyses, including thermogravimetry and scanning electron microscope. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2376–2381, 2007     

Photografting of PVC containing N,N‐diethyldithiocarbamate groups with vinyl monomers

Poly(vinyl chloride) (PVC) with pendent N,N‐diethyldithiocarbamate groups (PVC–SR) was prepared through the reaction of PVC with sodium N,N‐diethyldithiocarbamate (NaSR) in butanone and used as a photoinitiator for the grafting polymerization of three vinyl monomers [styrene (St), methyl methacrylate (MMA), and acrylamide (Am)]. The effects of ultraviolet (UV) irradiation time, PVC–SR amount, and the monomer amount on grafting and grafting efficiency were investigated. The results showed that PVC–SR could initiate the polymerization of three vinyl monomers effectively and obtained crosslinked copolymers. The grafting and grafting efficiency of styrene and methyl methacrylate were higher than those of acrylamide. The polymerization activity of three monomers was acrylamide > methyl methacrylate > styrene. By analyzing the UV spectrum of PVC–SR with a different irradiation time, it was confirmed that PVC–SR was dissociated mainly into macromolecular the sulfur radical PVC–S · and the small molecular carbon radical · C(S)N(C₂H₅)₂; the grafting polymerization mechanism was discussed. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2569–2574, 2000     

原位聚合聚氯乙烯树脂的合成及性能

研究了氯乙烯悬浮聚合时添加氯化聚乙烯(CPE)冲击改性剂、CaCO3填料、润滑剂及热稳定剂对聚合反应的影响，并对得到的可直接加工的原位聚合聚氯乙烯(RTUPVC)树脂的性能进行了表征。结果发现：CPE和CaCO3的加入均使达到相同压降的聚合时间缩短，氯乙烯聚合转化率相应减小；RTUPVC树脂的粒径随CPE粒径和用量的增大而增大，而CaCO3含量对RTUPVC树脂粒径影响不大；润滑剂和热稳定剂的加入，对聚合反应起延缓作用，但对RTUPVC树脂粒径影响不大；RTUPVC树脂加工塑化时间随CPE含量的增加而减少；相同CPE用量时，RTUPVC树脂的冲击强度和拉伸强度明显高于PVC/CPE共混物。     

Controlled synthesis of poly(vinyl acetate) by traditional radical emulsion polymerization

A new redox initiation system, potassium persulfate/N,N‐dimethylethanolamine, was used to initiate traditional radical emulsion polymerization of vinyl acetate at low temperature. Polymers were characterized using gel permeation chromatography, scanning electron microscopy and dynamic light scattering. The results showed that poly(vinyl acetate) with high molar mass and small dispersity (?) was successfully synthesized. © 2016 Society of Chemical Industry