锂电池用聚偏氟乙烯粘结剂

锂电池用粘结剂是制造锂电池的重要材料之一,可直接影响其性能.介绍了锂电池用粘结剂应具备的特性、种类及存在的问题;叙述了日本专利中,偏氟乙烯作为锂电池用粘结剂和用偏氟乙烯与第二及第三单体的共聚改性、聚偏氟乙烯与其他聚合物共混改性等的方法.     

聚乙烯醇/二氧化硅互穿网络膜的研究

采用溶胶凝胶法制备了聚乙烯醇/二氧化硅有机/无机互穿网络结构。扫描电子显微镜(SEM)观察到样品表面光滑,均匀;原子力显微镜(AFM)观察到样品中无机相与有机相呈互穿网络结构,且随无机物的增多两相分布更均匀;元素分析结果为纯PVA中w(O)为38%,随着无机物的增多w(O)逐渐降低为24.9%,是硅羟基与醇羟基之间脱去水,两相之间进行交联的结果;29SiNMR表明随无机物的增多,化学位移Q3的强度有所降低而化学位移Q4值却略有上升,说明硅羟基含量逐渐减少,两相交联程度逐渐增大,与元素分析结果相印证;热重曲线(TG)表明,无机物的加入使PVA的热降解温度由400℃提高到420℃,进一步证明两相之间已形成网状结构。     

超支化乙二胺三嗪聚合物对PPC/PBS共混体系的增强改性研究

以超支化乙二胺三嗪聚合物（HBETP）为改性剂,采用熔融共混法制备了聚碳酸亚丙酯（PPC）/聚丁二酸丁二醇酯（PBS）/HBETP共混物;利用动态热机械分析仪、热失重分析仪、电子万能试验机、旋转流变仪、扫描电子显微镜等,对其热性能、力学性能、流变性能、断面形貌等进行了表征。结果表明,当HBETP含量为0.5 %（质量分数,下同） 时,PPC/PBS/HBETP共混物在韧性基本保持不变的情况下,拉伸强度提高幅度最大,由7.56 MPa提高到11.22 MPa,增幅为49.6 %;HBETP的加入可以提高PPC/PBS的相容性,且适当的含量会使PPC/PBS的拉伸强度提升。     

PVDF-HFP凝胶型固体聚合物电解质改性研究进展

固体聚合物电解质具有质轻、安全、易加工等优点,在锂离子电池中具有巨大的应用价值。主要综述了以PVDF-HFP共聚物为基的聚合物电解质的研究工作,介绍了PVDF-HFP固体电解质的制备方法,主要讨论了PVDF-HFP电解质的改性措施,对今后的发展方向作了简单展望。     

密封双极性MH/Ni电池的研制及性能研究

报道了密封双极性MH/Ni电池的设计与开发。考察了电极厚度、密封技术及电解液用量等工艺条件对单体电池性能的影响,解决了双极性电池设计中的主要问题。研制开发了由4个单体电池组成的4.8V,2.8A·h密封双极性MH/Ni电池。测试结果表明,电池具有较低的内阻和良好的高倍率充放电性能。在模拟混合动力车工作环境实验中,电池的性能稳定,经过多次循环后性能没有明显衰减。这种密封双极性MH/Ni电池非常可能成为性能优异的电动车及混合动力车用电源。     

乳聚法制备聚苯胺复合膜及其电致变色性能研究

以十二烷基苯磺酸(DBSA)为掺杂剂,在非有机溶剂的两相体系中以聚乙烯醇(PVA)为成膜助剂,采用乳液聚合法合成了可直接用于制备电致变色膜的聚苯胺PAn/PVA乳液,用提拉成膜法制备了复合膜。研究了PVA含量、苯胺(An)与DBSA的量比、氧化剂过硫酸铵(APS)与An的量比及反应温度对膜的电致变色性、导电性的影响。结果表明:在w(PVA)为4.3%、n(An)∶n(DBSA)∶n(APS)=0.80∶1.00∶0.80、反应温度为5℃时,PAn/PVA复合膜具有较好的电致变色性及粘结性能。其本征态电化学活性的氧化峰电位范围出现在0.43V。     

Shellac-polyamidoamine: Design of a new polymeric carrier material for controlled release application

The development of a pH sensitive, biodegradable polymer from the combination of Shellac (a natural polymer secreted by lac insect) and polyamidoamine (PAA) (a synthetic polymer) yielded a new biocompatible polymer Shellac-PAA in a photopolymerization process. Scanning electron micrograph of Shellac-PAA shows an interesting heterogeneous surface morphology supported with observation of two different melting temperatures obtained from differential scanning calorimetric measurement. The equilibrium swelling properties of the polymeric material was studied as a function of pH and time in buffer solutions similar to that of gastric and intestinal fluids. The controlled release kinetics of a model colon specific drug 5-aminosalicylic acid showed Fickian diffusion behavior. The new polymer is biocompatible, biodegradable and, hence, projected as a new kind of polymer with improved properties, which can be a potential candidate for controlled release of therapeutic agents in colon specific diseases. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

苯胺-邻甲苯胺共聚物的合成及其性能研究

以苯胺、邻甲苯胺为单体,过硫酸铵为氧化剂,蒸馏水为溶剂,碘为掺杂剂制备了聚苯胺、聚邻甲苯胺以及它们的共聚物,通过FT-IR、UV-Vis、TG、XRD、SEM等测试手段对单聚物和共聚物进行了结构形态表征与性能分析.碘掺杂后的单聚物和共聚物的导电率有明显的改善,其中碘掺杂聚邻甲苯胺的导电率为1.14×10-3/cm,碘掺...     

Electrochemical synthesis of poly(5-nitroindole) on 316L-stainless steel in LiClO4-acetonitrile solution and its corrosion performance

The preparation of poly(5-nitroindole) (P5NI) coating was achieved on 316L-stainless steel (SS). Poly(5-nitroindole) was deposited via anodic oxidation of the corresponding monomer in acetonitrile (ACN) solution containing LiClO₄. The influence of P5NI coating against SS corrosion was studied in 3.5% NaCl solution by electrochemical impedance spectroscopy (EIS), anodic polarization curves and the open circuit potential–time (E_ocp–t) diagrams. The results obtained suggest that P5NI coating forms a sacrificial layer but the efficiency against corrosion is limited with increasing time.     

硅橡胶/水凝胶半互穿网络膜的制备研究

通过交联的聚甲基乙烯基硅橡胶膜含浸甲基丙烯酸β 羟乙酯单体溶液,然后以原位聚合的方法制得硅橡胶—水凝胶半互穿网络膜。用扫描电镜观察膜的横断面,并以X射线光电子能谱研究膜的表面组成。测试膜在水中的溶胀性能及膜对小分子药物的渗透性。     

复合酸掺杂PVA/PANI/Ag复合膜的电化学制备及性能研究

采用电化学法制备了硫酸(H2SO4)和磺基水杨酸(SSA)共掺杂的导电聚乙烯醇/聚苯胺(PVA/PANI)复合膜,采用正交设计法优化了工艺条件,研究了沉积银电流密度和时间、拉伸对复合膜电导率的影响。采用红外光谱、X射线衍射、扫描电镜对复合膜进行表征。结果表明,最佳条件下获得的PVA/PANI复合膜的电导率为22.72 S/cm;在此复合膜上以50 mA/cm2沉积2 min银可使复合膜的电导率提高到1250 S/cm;对2种复合膜进行适当的拉伸可使其电导率分别提高20.74 %和18.04 %。复合膜有一定程度的结晶,经拉伸后其结晶度有所提高。     

Polymer electrolyte membranes composed of an electrospun poly(vinylidene fluoride) fibrous mat in a poly(4‐vinylpyridine) matrix

Newly proposed polymer electrolyte membranes (PEMs) composed of an electrospun poly(vinylidene fluoride) (PVDF) fibrous mat embedded in a poly(4‐vinylpyridine) (P4VP) matrix were successfully fabricated in order to improve the mechanical and dimensional stabilities and ionic conductivity of membranes in lithium rechargeable batteries. Fourier transform infrared spectroscopic analysis showed that as a result of the use of a high voltage during electrospinning the crystalline structure of PVDF changed partially from α‐phase to β‐phase. Energy‐dispersive X‐ray spectroscopy confirmed the existence of crosslinked P4VP in the PVDF fibrous mat. The electrolyte uptakes of PVDF and PVDF/P4VP composite mats were higher than that of PVDF cast film. The tensile properties of PVDF/P4VP composite mat were considerably improved compared to those of the pristine PVDF fibrous mat under both dry and wet (soaked with electrolyte) conditions. In addition, the mechanical and dimensional stabilities of the PVDF/P4VP composite PEM were further enhanced due to crosslinking between the P4VP chains. Furthermore, the PVDF/P4VP composite PEM exhibited an ionic conductivity that was an order of magnitude higher than that of traditional PVDF film. © 2012 Society of Chemical Industry     

The substituent effects on the structure and surface morphology of polyaniline

In this work, poly(2‐fluoroaniline), poly(2‐chloroaniline), poly(2‐methylaniline), and poly(N‐ethylaniline) were prepared by a self‐assembly method using an oxidizing system consisting of a dopant anion, p‐toluene sulfonate with ammonium peroxydisulfate. The effects of substituents on the surface morphology, conductivity, molecular weight, spectral and thermal properties of the polymers were studied. SEM results revealed that the surface morphology of the resulting polymers changed from nanofiber to spherical structure by changing the substituent on the aniline monomers. The structure and properties of these conducting films were characterized by FTIR, UV‐vis, elemental analysis, TGA, conductivity, and cyclic voltammetry. The polymer films show electroactivity in monomer free solution. Molecular weight of the polymers was determined by gel permeation chromatography. The dry electrical conductivity values of the substituted‐polyanilines were found to be lower than that of PANI. The results revealed that the molecular structures of the polymers were similar to those of the emeraldine form of polyaniline. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Synthesis and characterization of proccessible polyaniline derivatives for corrosion inhibition

This article reports the synthesis and characterization of copolymers based on aniline and substituted anilines by using dodecylbenzene sulfonic acid as a dopant. The copolymers were soluble in organic solvents, such as methanol, ethanol, isopropanol, N‐methylpyrrolidinone, dimethylsulphoxide, and have conductivity of the order of 1.5 to 10^?7 S/cm depending upon the monomer ratios and extent of dopant used. The effect of substituents like 2‐methyl, 2‐ethyl, and 2‐isopropyl groups on the electrochemical, conductivity, thermal stability, solubilization, and spectroscopic behavior of the copolymers has been evaluated. The composition of the copolymers was determined by ¹H‐NMR spectroscopy. Corrosion inhibition behavior of the copolymers in 1.0N HCl has been evaluated using linear polarization resistance method and Tafel extrapolation method. The corrosion efficiency depends upon the copolymer composition and it increased with increasing amount of 2‐alkyl aniline in the feed. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Synthesis and functionality of poly(N-vinylalkylamide). X. A novel aqueous two-phase system based on thermosensitive polymers and dextran

The use of thermosensitive polymers in an aqueous two-phase system was studied. Poly(N-isopropylacrylamide) (PNIPAAm) and poly(N-vinylisobutyramide) (PNVIBA) were used as thermosensitive polymers. Both polymers could form aqueous two-phase with dextran, respectively. The phase diagrams of each system were successfully obtained. Using myoglobin as a model protein, a preliminary separation study was performed. The separation ability of both polymers was higher than that from the poly(ethylene glycol)-dextran system. Protein separation ability appeared to be related to the hydrophilic/hydrophobic balance of the polymers. Both PNVIBA and PNIPAAm rich phases maintained their thermosensitivity after two-phase formation. PNVIBA and PNIPAAm are useful as polymers for a functional aqueous two-phase system. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 2545–2548, 1999     

锂电池用PEO基固态聚合物电解质研究进展及应用

介绍了锂电池用聚氧化乙烯(PEO)基固态聚合物电解质的研究进展,论述了国内外在PEO改性、锂盐改进和制备PEO-无机复合聚合物电解质等三方面在提高其电导率、电化学稳定窗口和离子迁移数等性能进行的研究,综述了PEO基聚合物电解质的应用情况.     

新型聚氨酯微球制备及其药物释放规律的研究

以低相对分子质量生物可降解DL-聚乳酸二醇和六亚甲基二异氰酸酯为原料,通过悬浮聚合法合成了一种新型聚氨酯微球(PUMS),考察了扩链剂1,4-丁二醇(BDO)的含量对微球表面形态和药物包封率的影响。用傅立叶变换红外光谱(FFIR)、扫描电子显微镜(SEM)以及激光粒度分析仪对微球的化学结构、表面形态、粒径及其分布进行了表征,并以溴百里酚兰为亲水性模型药物,初步研究了微球的药物释放行为。结果表明,合成的微球的平均粒径47um,粒径分布在10～90um之间;微球表面有孔,但随着BDO含量的增加,微球表面变得相对粗糙,孔数减少,孔径减小,直至孔消失;BDO含量的增加也使模型药物的包封率减小,释放速率变慢;药物释放初期出现程度不同的“暴释”现象,但随后近似于零级释放。     

聚苯胺及其衍生物聚对苯二胺的研究进展

介绍了聚苯胺的合成方法——化学氧化聚合法和电化学聚合法,以及微/纳米聚合物的合成方法——模板法,总结了聚苯胺的衍生物聚对苯二胺的研究进展,指出了聚对苯二胺的发展前景.     

高分子固体电解质研究新进展

高分子固体电解质(SPE)是一类全新的电解质,具有质轻、易成膜、黏弹性好和稳定性好等许多无机电解质和有机溶剂电解质不可比拟的性能,近年来研究进展很快。介绍高分子固体电解质类型及其性能提高的途径。     

Novel microporous poly(vinylidene fluoride)‐graft‐poly(tert‐butyl acrylate) electrolytes for secondary lithium batteries

BACKGROUND: Much interest has recently been shown in improving the performance of lithium‐ion polymer batteries with gel polymer electrolytes (GPEs) due to a rapid expansion in industrial demand. Novel GPEs based on poly(vinylidene fluoride)‐graft‐poly(tert‐butyl acrylate) (PVDF‐g‐tBA) microporous mats are suggested in this study. RESULTS: Microfibrous polymer electrolytes were prepared using electrospinning and characterized for extent of grafting, morphology, crystallinity, electrochemical stability, ionic conductivity, interfacial resistance and cell cycleability. The degree of crystallinity was lower for tBA‐grafted PVDF mats than that of neat PVDF. The PVDF‐g‐tBA showed an improvement in the ionic conductivity, electrochemical stability, interfacial resistance and cyclic performance. CONCLUSION: The tBA‐grafted PVDF microporous electrolytes are promising candidates for enhancing the performance of lithium‐ion polymer batteries. Copyright © 2008 Society of Chemical Industry