Preparation of conducting polymer composites: effects of porosity on electrical conductivity

To prepare conducting polymer composites, porous polymethyl methacrylate (PMMA) particles with different specific surface areas were prepared by seeded emulsion polymerization and solvent extraction. The dried porous particles were imbibed with the oxidant solution and adsorbed pyrrole from a solution. The incorporation of pyrrole into the porous particles was achieved by chemical oxidative polymerization. The effects of various polymerization parameters on the electrical conductivity were systematically investigated. The important factors affecting conductivity were the porosity of the host polymer particles and the solvent polarizability. © 1998 SCI.     

原位聚合制备有机累托石/聚甲基丙烯酸甲酯纳米复合凝胶聚合物电解质

通过自由基引发,以有机增塑剂为溶剂,用原位聚合的方式制备出有机累托石/聚甲基丙烯酸甲酯[organic-modified rectorite/poly(methyl methacrylate),OREC/PMMA]凝胶聚合物电解质(gel polymer electrolyte,GPE),研究了不同的分散工艺对纳米GPE(nano-GPE,NGPE)膜性能的影响.通过X射线衍射和透射电镜探讨NGPE的微观结构,并初步研究了NGPE膜的离子电导率(σ)和5%质量损失率对应的初始热分解温度(θi).结果表明:OREC片层精细呈解离状,良好地分散在凝胶体系中.随OREC添加质量(下同)的增加,NGPE的σ及θi均呈现先增大后减小的趋势.当OREC的添加量为5%时,具有较高的σ和θi.     

Structure and properties of an organic rectorite/poly(methyl methacrylate) nanocomposite gel polymer electrolyte by in situ synthesis

The synthesis of organic‐modified rectorite (OREC)/polymethyl methacrylate (PMMA) nanocomposite gel polymer electrolyte (NGPE) via in situ polymerization was investigated using free radical initiator in an solution, in which organic plasticizer, propylene carbonate(PC) acted as a solvent. A serious of NGPE membranes with different OREC content were prepared and characterized. The dispersion and exfoliation statuses of the OREC in the prepared NGPE membranes were analyzed through X‐ray diffraction (XRD) and transmission electron microscope (TEM), and the results indicated that for the NGPE with 5 wt % OREC membrane, OREC was partly exfoliated and well dispersed in the gel polymer electrolyte system. The electrochemical properties of the NGPE were determined by alternating current (AC) impedance spectroscopy, which illustrated that the ionic conductivity of the nanocomposite gel polymer electrolyte firstly increased and then decreased with increasing OREC content. Meanwhile, the maximum value of ionic conductivity for nanocomposite gel polymer electrolytes was obtained when organic clay amount was 5 wt %. The interactions among the components of the NGPE were investigated by Fourier transform infrared (FTIR) spectroscopy. It was shown that there were specific interactions between OREC and the other components, which may influence the conductivity and the stability of GPEs. Finally, an thermal stability enhancement was presented by NGPE with 5 wt % OREC compared with GPE, which was determined by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

原位聚合有机累托石/聚甲基丙烯酸甲酯凝胶聚合物电解质的性能

以有机增塑剂聚碳酸丙烯酯(propylene carbonate,PC)为聚合反应溶剂,通过自由基引发原位聚合法制备了有机累托石/聚甲基丙烯酸甲酯(organic-modified rectorite/polymethyl methacrylate,OREC/PMMA)纳米复合凝胶聚合物电解质(nanocomposite gel polymer electrolyte,NGPE).用交流阻抗法分析了凝胶电解质的电性能,并研究了温度对电性能的影响.通过红外光谱分析其组分间的相互作用.用差示扫描量热分析和热失重分析分析凝胶电解质的热稳定性.结果表明:OREC/PMMA组成的NGPE的本体阻抗值随OREC添加量的增加呈现出先减小后增大的趋势,当OREC的添加质量为5%时,NGPE在不同温度下均具有最大的离子电导率(σ).OREC与PC,PMMA及锂盐之间存在一定的相互作用,从结构的角度解释了OREC添加提高体系σ的机理.添加OREC能在一定程度上改善体系的凝胶热稳定性.     

Chemically Modified Polyvinyl Butyral Polymer Membrane as a Gel Electrolyte for Lithium Ion Battery Applications

A novel porous membrane of chemically modified polyvinyl butyral (mPVB), with improved thermal properties and chemical stability for lithium ion battery applications, is successfully synthesized by utilizing the chain extension reaction of the OH units from PVB. The porous mPVB membranes are obtained via the tape casting and phase inversion method. The corresponding gel polymer electrolyte (GPE) is achieved by immersing the as‐prepared membranes in the liquid electrolyte. The electrochemical performances of the GPE show that the mPVB membranes have the features of good uniformity, high porosity ( ≈ 90%), great thermal stability, and high mechanical strength. Moreover, the GPE exhibits good chemical stability, a wide electrochemical window, as well as high ionic conductivity ( ≈ 1.21 × 10^?3 S cm^?1). A test of a Li/GPE/LiFePO₄ battery cell shows a capacity of 147.7 mAh g^?1 and excellent cycling stability, demonstrating the great potential of the mPVB‐based GPE for lithium ion battery applications.     

PSt／PBA／PMMA三元互穿绿色涂料的研制

研究了制备PSt／PBA／PMMA LIPN涂料的新方法。采用种子乳液聚合技术制备了PSt／PBA／PMMA（聚苯乙烯／聚丙烯酸酯／聚甲基丙烯酸甲酯）乳胶型互穿网络聚合物涂料。结果表明当单体配比St：BA：MMA=4：3：2,交联剂用量为单体总量的1．5％,引发剂用量为1．2％,反应温度为70％左右时,涂料综合性能优良。说明采用乳液聚合技术合成的三元互穿乳液涂料较传统的丙烯酸酯类涂料性能优良,该涂料以水为溶剂,是一种典型的绿色涂料。     

Permeation characteristics of poly(vinyl alcohol)–poly(vinyl acetate) composite porous membranes

Poly(vinyl alcohol) (PVAc) composite porous membrane has been prepared from PVAc latex film by extraction with acetone. The PVAc latex was prepared by emulsion polymerization of vinyl acetate in the presence of PVA, employing the hydrogen peroxide–tartaric acid systemm as an initiator. The extraction degree of PVAc could be controlled in a wide range by changing the addition method of the initiator, and, acoordingly, PVA–PVAc omposite porous membranes which had variosu void volumes were obtained. The maximum void volume attained was ca. 90%. Permation characteristics of organic solvents wre investigated on the membranes whose extraction degrees were 95.6% and 80.7%. Thge feeds were benzene, n-hexane, cyclohexane, and their mixtures. neither swelling nor shrinkage in tje appearance size of the while benzene hardly permeated even at 20 kg/cm². The grafted PVAc in the mebrane was removed or converted into grafted PVA by treatment with sodium methylate, and then the depression of benzene permeation was lost. The grafted PVAc was suggested to be localizd on the cell wall and was found to function as a valve which closes with nenzene or a good solvent for PVAc and opens with n-haxane or a poor solvent for PVAc.     

疏水缔合水溶性聚合物的合成与应用研究进展

综述了疏水缔合水溶性聚合物的合成和应用的研究进展。合成方法包括大分子反应法、共聚法、乳液聚合法、阴离子聚合法、活性可控自由基聚合、超声波法、超临界二氧化碳介质法等,应用领域包括石油工业、涂料工业、污水处理、生物医药材料、工程材料等,并且展望了新的合成方向和应用前景。     

Synthesis,structure, and properties of new methacrylic derivatives of naphthalene‐2,3‐diol

The synthesis of a new monomer, 2,3‐(2‐hydroxy‐3‐methacryloyloxypropoxy)naphthalene, and its copolymerization with divinylbenzene is presented. This monomer was obtained from naphthalene‐2,3‐diol in a two‐step synthesis. Copolymers in the form of porous microspheres were prepared by a suspension‐emulsion polymerization method. As pore‐forming diluents, toluene, 1‐decanol, benzyl alcohol, and their mixtures were used. In studies of their porous structure, two methods were used: the adsorption of nitrogen at low temperatures, which provided information about the porous structure of the material in a dry state, and inverse exclusion chromatography, which provided information about the porous structure of the polymer swollen by a good solvent. The obtained results suggest that the porous structures for the dry and swollen polymers were different. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1886–1895, 2006     

增塑型锂离子电池聚合物电解质

从组成聚合物电解质的聚合物基材和电解液两方面进行分析,介绍了最近几年凝胶型、微孔型和复合型聚合物电解质的研究现状,比较了它们的制备方法、性能和特点,探讨了锂盐、增塑剂、离子液体和单离子导体等对聚合物电解质性能的影响,并简要评述了聚合物锂离子电池未来发展的前景趋势。     

Preparation of porous polymer materials using water‐in‐oil gel emulsions as templates

Water‐in‐oil gel emulsions consisting of water and n‐butyl acrylate were successfully prepared using N‐3‐hydroxybutylcarbonyl‐l ‐isoleucylaminooctadecane and sorbitan monooleate (Span 80) as gelator and surfactant, respectively. Stable gel emulsions were formed using aqueous phase fractions (APFs) ranging from 10 to 90 vol%. Creaming, flocculation and coalescence were not observed. Low‐temperature polymerization of the gel emulsions with a redox initiator gave the corresponding low‐density, highly porous poly(n‐butyl acrylate)s (PBAs). The microstructures of the PBAs were observed using scanning electron microscopy. All the porous PBAs comprised numerous spherical structures whose sizes could be controlled by adjusting the gel emulsion APF. The densities and porosities of the porous PBAs decreased and increased, respectively, with increasing APF. The absorption capacities of the porous PBAs in organic solvents were studied. The porous PBAs selectively absorbed kerosene from water instantly and the kerosene could then be recovered by physical compression of the PBAs. Further porous polymers were prepared from gel emulsions containing styrene, methyl methacrylate (MMA) or 2‐ethylhexyl acrylate (EHA) as continuous oil phases. The order of absorption capacity and swelling ratio in kerosene was poly(EHA) > PBA ? poly(MMA). Porous copolymers were also prepared from gel emulsions containing a mixture of EHA and MMA as the oil phase. Their absorption and swelling in liquids could be controlled by changing the ratio of EHA and MMA in the gel emulsions. poly(EHA‐co‐MMA) (6:4) was the best polymer when absorption capacity, swelling ratio and durability were simultaneously considered. © 2018 Society of Chemical Industry     

无皂乳液聚合法合成聚苯乙烯微球应用于准固态电解质染料敏化太阳能电池

制备了一种提高染料敏化太阳能电池短路电流和电池光电转化效率的准固态凝胶电解质,该电解质含有5%高聚物PVDF-HFP和2% TiO₂纳米颗粒。另外,通过乙醇相无皂乳液聚合法合成了大小均一的聚苯乙烯微球,并用于制备染料敏化太阳能电池的多孔光阳极。研究了准固态电解质和液态电解质应用于不同光阳极染料敏化太阳能电池的规律。结果表明,与液态电解质相反,准固态电解更适用于孔洞较多的光阳极,在相同测试条件下,电池的短路电流由12.80 mA·cm^-2提高到13.53 mA·cm^-2,效率比液态提高11.43%,达到6.63%。     

Synthesis and characterization of porous poly(methacrylic acid‐co‐triethylene glycol dimethacrylate) by seed emulsion polymerization

Porous poly(methacrylic acid‐co‐triethylene glycol dimethacrylate) (poly MAA‐co‐3G) particles in the size range of 10–40 μm were prepared via seed emulsion polymerization. Mixtures of linear polymer, solvent, and/or nonsolvent were used as inert diluents. The prepared porous polymer was converted using hydroxylamine hydrochloride and sodium methoxide into the corresponding poly(hydroxamic acid). The surface area of the porous copolymer particles was determined colorimetrically. The effect of the diluent type and concentration on the surface area of the prepared porous polymer was examined. The metal ion absorption capacity of the resin toward the different metal ions was examined using an atomic absorption spectrophotometer. The thermal stability of the polymers was examined by thermal gravimetric analysis. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 1209–1215, 2000     

Gel polymer electrolyte with semi-IPN fabric for polymer lithium-ion battery

A new type of semi-IPN gel electrolyte was prepared by thermal polymerization in this article. At first, the crosslinkable PEG200 (MXPEG) was prepared by condensation reaction, then the crosslinkable components were blent with PMMA and heated under vacuum to form polymer blends with semi-IPN fabric. Differential scanning calorimetry and X-ray diffraction spectroscopy were used to investigate the thermal properties and crystalline/amorphous structure of the prepared polymer blends. With semi-IPN fabric, they present amorphous absolutely. For semi-IPN gel electrolyte, the mechanical and the electrochemical properties are varied with the quantity of absorbed liquid electrolyte. Ion-conductivity behavior for semi-IPN gel electrolyte measured by means of AC impedance spectrum showed that the best data was 1.62 × 10⁻³S cm⁻¹ at room temperature, and Arrhenius-type relationship was obeyed in the temperature dependence of ionic conductivity. In addition, the electrochemical stability window of the semi-IPN gel electrolyte was 4.6 V. All the properties showed that the prepared semi-IPN gel electrolyte was expected to have applications of electrolyte for lithium-ion polymer secondary batteries. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Synthesis and properties of new thermosensitive polymer systems

The controlled thermal release of aqueous solvent mixtures from polymeric gel particles was investigated. A new type of a polymeric gel consisting of a maleic anhydride/poly(ethylene glycol) condensation product as a crosslinking macromonomer and acrylamides was synthesized by solution or inverse emulsion polymerization for the investigation. Afterward a shell of crosslinked polystyrene was coated to stabilize this new kind of “microcontainer” for the application. This concept was shown as generally useful for various mixtures of organic solvents and water. The cloud point temperature of the polymer gel strongly depended on the following parameters: the type and content of organic cosolvent, the degree of polymerization and constituents of the polyester moiety, and the type and content of the comonomers. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

An efficient preparation of porous polymeric microspheres by solvent evaporation in foam phase

This paper reports an efficient method of preparing porous polymeric microspheres by solvent evaporation in foam phase, in which phase separation between polymer and porogen occurs in foam phase instead of that in water phase by using the traditional solvent evaporation method. The method provides outstanding features, including being time-saving, of high-yield and able for continuous production, in which formation of porous polymeric microspheres finished within 3 min with a high production yield up to approximate 95 wt% and the process was able to be developed into a continuous process for production of porous polymeric microspheres. It was also universal to non-crosslinked polymers since the method is a development on the traditional emulsion solvent evaporation method. The new method is efficient and can be used potentially on the industrial scale for continuous production of porous polymeric microspheres.     

原位构建富氟SEI的凝胶电解质用于金属锂二次电池

以六氟磷酸锂（LiPF₆）为四氢呋喃的聚合引发剂制备凝胶电解质,同时作为氟源在金属锂负极表面原位构建富含LiF的固态电解质界面层（solid electrolyte interface,SEI）来抑制锂枝晶的生长以及金属锂/电解液之间的副反应。所制备的凝胶电解质具有较高的室温离子电导率（1.33 mS·cm^-1）和较宽的电化学稳定窗口（4.5 V）。原位聚合方式组装金属锂对称电池循环后,锂负极表面没有明显的锂枝晶和被损毁的形貌出现;XPS结果表明锂负极表面生成了富含LiF的SEI。组装的LiFePO₄全电池在1 C的电流密度下,稳定循环400周后仍保持118.7 mAh·g^-1的放电比容量。得益于四氢呋喃在开环聚合反应过程中,促进了LiPF₆分解反应平衡的正向移动,在锂负极表面形成稳定的富含LiF的SEI,能够抑制锂枝晶的生长并防止其被持续性的腐蚀破坏。     

原位构建富氟SEI的凝胶电解质用于金属锂二次电池

以六氟磷酸锂（LiPF₆）为四氢呋喃的聚合引发剂制备凝胶电解质,同时作为氟源在金属锂负极表面原位构建富含LiF的固态电解质界面层（solid electrolyte interface,SEI）来抑制锂枝晶的生长以及金属锂/电解液之间的副反应。所制备的凝胶电解质具有较高的室温离子电导率（1.33 mS·cm^-1）和较宽的电化学稳定窗口（4.5 V）。原位聚合方式组装金属锂对称电池循环后,锂负极表面没有明显的锂枝晶和被损毁的形貌出现;XPS结果表明锂负极表面生成了富含LiF的SEI。组装的LiFePO₄全电池在1 C的电流密度下,稳定循环400周后仍保持118.7 mAh·g^-1的放电比容量。得益于四氢呋喃在开环聚合反应过程中,促进了LiPF₆分解反应平衡的正向移动,在锂负极表面形成稳定的富含LiF的SEI,能够抑制锂枝晶的生长并防止其被持续性的腐蚀破坏。     

丙烯酸酯互穿网络聚合物的合成和性能

以十二烷基硫酸钠为乳化剂、丙烯酸乙酯为软单体、苯乙烯为硬单体 ,二乙烯基苯或三乙二醇二丙烯酸酯为交联剂 ,先以两步法合成软单体聚合物网络 ,随后加入硬单体溶胀并聚合。研究了软硬单体配比、交联剂和聚合条件对乳液聚合稳定性、放置稳定性和转化率等的影响 ,测定了互穿聚合物网络的 Tg和形态结构、加工和性能。结果表明 ,这种互穿聚合物网络为可以反复可塑加工、并具较高力学性能新型热塑性弹性体     

聚苯胺溶解性研究

以苯胺氧化聚合和乳液聚合两种方法合成聚苯胺(PAn),研究了溶剂、聚合方法、反应温度、导电态、十二烷基苯磺酸用量等因素对聚苯胺溶解性的影响。结果表明,N-甲基吡咯烷酮是本征态聚苯胺的良溶剂,用乳液聚合法合成的聚苯胺其溶解性明显高于化学氧化法合成的聚苯胺,当乳液中十二烷基苯磺酸∶苯胺(摩尔比)=2.0∶1,聚合温度25℃时合成溶解率大的PAn。