Flexibility improvement of epoxy resin by chemical modification

Epoxy resin was chemically modified with carboxyl‐terminated poly(ethylene glycol) adipate (CTPEGA) and the modified epoxy networks were made by curing with an ambient‐temperature hardener. The modified epoxy networks containing various concentrations of CTPEGA were characterized for their tensile, flexural and impact properties. It was observed that the mechanical strength gradually decreases and the strain increases with increasing CTPEGA concentration. However, the toughness and impact strength gradually increase with increasing CTPEGA concentration, attain a maximum and then decrease. The optimum CTPEGA concentration was found to be 20 phr. Fracture surface analysis by scanning electron microscopy indicates massive plastic deformation in modified networks. Copyright © 2004 Society of Chemical Industry     

Facile fabrication and modification of epoxy acrylate latexes by epoxy resin and silane coupling agent

For the purpose of obtaining solvent-free epoxy acrylate latexes of good stability and excellent integrated performance, the epoxy acrylate latexes were fabricated using facile semi-continuous emulsion polymerization with varying amounts of epoxy resin and were modified by a silane coupling agent γ-methacryloxypropyltrimethoxysilane (KH-570). The effects of epoxy resin and KH-570 amounts on the performance of latexes and films were investigated from the aspects of particle size, morphology, tensile measurements, resistance properties, adhesion force, and thermal behavior. The results indicated that the acrylate monomers did graft onto the molecular chain of E-51 characterized by both epoxy value and Fourier transform infrared. Additionally, an emulsion of 80–100 nm particle size with a narrow distribution was obtained. The latex films retain resistances to satisfactory water, acid, alkali, and alcohol while maintaining good thermal stability, adhesion force, and flexibility. The importing of KH-570 could reinforce the spatial structure and cross-linking density and then improve the tensile strength of the latex films properly while keeping other performances well. This work provides a facile pathway for the optimized performance for epoxy acrylate latexes, and represents a tendency for environmental protection.     

改性氮化铝/环氧树脂复合材料的制备研究

采用共混-浇注成型法制备氮化铝/环氧树脂AlN/E-51复合材料。借助静止沉淀法、接触角、傅立叶红外光谱FT-IR和热失重TGA等进行分析表征。探讨了AlN用量和表面改性对复合材料力学性能的影响。结果表明,KH-560以化学键结合在AlN表面。复合材料的弯曲和冲击强度均随AlN用量的增加而提高,当AlN用量为10%时,复合材料的力学性能最佳。()()()     

Flexibility improvement of short glass fiber reinforced epoxy by using a liquid elastomer

In certain applications of fiber reinforced polymer composites flexibility is required. The aim of this study was to improve flexibility of short glass fiber reinforced epoxy composites by using a liquid elastomer. For this purpose, diglycidyl ether of bisphenol-A (DGEBA) based epoxy matrix was modified with hydroxyl terminated polybutadiene (HTPB). A silane coupling agent (SCA) was also used to improve the interfacial adhesion between glass fibers and epoxy matrix. During specimen preparation, hardener and HTPB were premixed and left at room temperature for an hour before mixing with epoxy resin to allow possible reactions to occur. In order to compare flexibility of the specimens flexural tests were conducted and the data were evaluated numerically by using a derived relation. Test data and scanning electron microscope analysis indicated that surface treatment of glass fibers with SCA, and HTPB modification of epoxy matrix improved flexural properties especially due to the strong interaction between fibers, epoxy, and rubber. It was also observed that HTPB modification resulted in formation of relatively round rubber domains in the epoxy matrix leading to increased flexibility of the specimens.     

纳米Al2O3填充液体橡胶／环氧树脂复合材料的性能研究

用端异氰酸酯基聚丁二烯液体橡胶与环氧树脂制得端异氰酸酯基聚丁二烯液体橡胶／环氧树脂聚合物（ETPB）。在ETPB中分别加入质量分数5％和10％的纳米Al2O3,并选择适宜的固化剂固化,制得ETPB／Al2O3复合材料。考查了ETPB与ETPB／Al2O3复合材料的力学性能,研究了该材料的滑动摩擦磨损率与滑动速度之间的关系,并用扫描电子显微镜（SEM）对几种材料磨损表面进行了观察。结果表明,通过填充纳米Al2O3无机粒子可显著提高ETPB的性能,当填充量为5％时,ETPB／Al2O3复合材料性能最佳。     

Copper particles/epoxy resin thermosetting conductive adhesive using polyamide resin as curing agent

Thermosetting conductive adhesive (TCA) comprised of epoxy resin E‐51 as matrix, Cu microparticles and nanoparticles modified by silane coupling KH550 as conductive fillers, polyamide resin with low molecular weight as curing agent, and some other additives. It was reported creatively a new liquid curing agent, which solved successfully some difficult problems during preparation of TCA, such as limit of quantity of conductive fillers. Therefore, application of this liquid curing agent decreased greatly the resistivity of TCA under the condition of keeping enough adhesion strength. Antioxidized and mixed Cu particles were developed as conductive fillers in place of expensive Ag. The results showed that optimum conditions of conductive adhesive composed of 16 wt % of epoxy resin E‐51, 8 wt % polyamide resin, 65 wt % of Cu microparticles and nanoparticles, 1.3 wt % of silane coupling agent, and 9 wt % of other additives with curing time for 4 h at 60°C. The adhesion strength reached 16.7 MPa and the bulk resistivity was lower than 3.7 × 10^?4 Ω cm. The variation of bulk resistivity was less than 15% at high temperature (100°C). © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

端羟基聚丁二烯改性水性聚氨酯的合成与性能

以端羟基聚丁二烯(HTPB)、聚醚二元醇(N-220)、异佛尔酮二异氰酸酯(IPDI)为主要原料,制备了改性水性聚氨酯(WPU)。研究了端羟基聚丁二烯(HTPB)的含量对聚氨酯乳液粒径、贮存稳定性,以及对涂膜耐水性、力学性能、低温柔韧性的影响。结果表明:在预聚反应中,固定总n(—NCO)∶n(—OH)为1.3,w(DMPA)为6%,HTPB添加量在40%(占聚醚N-220的量)以下时,粒径变化不大,乳液稳定性较好;针对不同HTPB添加量,控制好亲水基团的含量,可以获得分散性良好、贮存稳定的聚氨酯乳液;随着HTPB添加量逐渐增大,涂膜的拉伸强度逐渐增大后变小,断裂伸长率和吸水率逐渐减小后变大,低温柔韧性变好。当HTPB添加量在30%左右,涂膜的综合性能最佳。     

环氧树脂化学改性有机硅树脂的方法综述

环氧改性有机硅树脂可提高有机硅树脂的力学性能和粘接性能,还可降低有机硅树脂的固化温度.归纳总结了环氧树脂化学改性有机硅树脂的4种反应类型:1)缩聚反应;2)环氧基的开环聚合反应;3)硅氢加成反应;4)引入环氧基的反应.对该领域的近期研究成果进行了简要的综述,并展望了该领域未来的发展方向.     

液体橡胶／环氧树脂复合材料的制备与性能研究

用端异氰酸酯基聚丁二烯液体橡胶与环氧树脂制得端异氰酸酯基聚丁二烯液体橡胶与环氧树脂反应物（ETPB）。在ETPB中加入纳米Al2O3,并选择适宜的固化剂固化,制得ETPB／Al2O3复合材料。测试了ETPB和ETPB／Al2O3复合材料于石英砂-水介质中的冲蚀磨损性能,并用扫描电子显微镜（SEM）对材料磨损表面进行了观察。结果表明,ETPB和ETPB／Al2O3复合材料在不同线速度下,随着线速度的增加冲蚀磨损率也随着增加。     

环氧端基酚酞聚芳醚腈改性环氧树脂胶粘剂性能的研究

通过差示扫描量热 (DSC)、热解重量分析 (TGA)和粘接强度的测定 ,对环氧端基酚酞聚芳醚腈改性的环氧树脂胶粘剂的性能进行了研究     

环氧/氢氧化铝复合材料性能研究

采用水解的KH-560处理微米级Al(OH)3粉末,改善其与树脂基体的表面相容性。通过FTIR对处理后的Al(OH)3进行了表征。优化了偶联剂水解条件及用量,并对不同Al(OH)3填充量的环氧/氢氧化铝复合材料分别采用热常数分析仪及电子万能试验机测试了其热导率和力学性能。结果表明,最佳水解条件为8%的KH-560在pH=4.5溶液中室温水解40 min。当KH-560的质量分数为Al(OH)3的10%左右时,效果最优。材料的热导率随着Al(OH)3填充量的增加而增高。填充量为6%时,力学性能达到最优。     

环氧树脂增韧改性技术研究进展

综述了通过基体树脂和柔性固化剂两个角度增韧改性环氧树脂技术的研究进展并介绍了各种增韧方法的机理和特点。其中基体树脂增韧包括采用橡胶、热塑性树脂、聚硅氧烷、核-壳聚合物、刚性粒子、液晶聚合物、膨胀性单体、无机纳米粒子以及树枝型高分子等。柔性固化剂包括胺类、酸酐、聚合物等。     

碳纳米管在环氧树脂改性中的应用研究进展

阐述了碳纳米管(CNTs)在EP(环氧树脂)基复合材料中的应用情况,着重讨论了CNTs表面改性的原因及其对EP基复合材料性能(包括力学性能、热性能和电性能等)的影响,并介绍了国内外该类复合材料的研究成果。最后对CNTs/EP基复合材料的研究方向进行了展望。     

端羟基聚丁二烯的应用、合成方法与表征手段

论述了近年来端羟基聚丁二烯的研究进展及其应用，主要是对阴离子法合成端羟基聚丁二烯的合成方法及其表征手段进行了评述，指出民用丁羟胶的应用前景广泛。     

邻甲酚醛环氧/改性凹凸棒土复合材料的制备

采用硅烷偶联剂KH560对提纯后的凹凸棒土(AT)进行改性,得到有机化凹凸棒土,并对其进行FTIR和TG表征,结果表明,KH560对凹凸棒土起到了良好的修饰改性作用。采用熔融复合法制备了AT质量分数为0～5%的邻甲酚醛环氧/凹凸棒土纳米复合材料(ECN/(KH560-AT)x),对其进行了扫描电镜(SEM)分析、动态力学分析(DMA)和热重分析以及力学性能测试。结果表明,KH560-AT的加入使复合材料断裂由脆性断裂向韧性断裂转变。ECN/KH560-AT复合材料的拉伸强度、冲击强度和Tg可比纯ECN分别高出54.12%、78.95%和37.5℃,KH560-AT的加入明显提高了复合材料的力学性能和耐热性。     

端异氰酸酯聚丁二烯液体橡胶初步表征及应用

用ＩＲ光谱和分子量变化初步表征端异氰酸酯聚丁二烯液体橡胶（ＩＴＰＢ）,用ＩＲ证明了ＩＴＲＢ改性环氧树脂Ｅ—４４化学键合作用的存在。ＩＴＲＢ改性环氧树脂抗冲击强度与剪切强度的结果表明ＩＴＲＢ最佳用量在２４份左右。ＩＴＲＢ在水力机械、电子灌封及建筑防水行业的优异使用性能展示了ＩＴＲＢ良好的应用前景     

环氧树脂改性研究进展

综述了近年来国内外环氧树脂的改性机理和方法,包括结构改性、橡胶改性、树脂改性、有机硅改性、膨胀单体改性和无机填料改性等。     

纳米粒子改性环氧树脂的研究进展

论述了环氧树脂基纳米复合材料的研究发展概况,主要包括:无机纳米粒子结构特性、环氧树脂基纳米复合材料的制备方法、固化机理及环氧树脂基纳米复合材料的性能和作用机制。最后指出了目前研究中存在的一些问题,并对其发展做出了简要的述评。     

甲基丙烯酸改性环氧树脂改进环氧胶膜性能研究

甲基丙烯酸(MAA)和环氧树脂(EP)进行反应后,添加偶氮二异丁腈(AIBN)和丙烯酸异辛酯,合成的含有丙烯酸树脂链段的环氧树脂作为增韧剂,制备成环氧胶膜。改性后的环氧树脂胶膜剪切强度及剥离强度明显提高,DSC测试显示体系的耐热性能损失不大,用红外光谱分析了固化过程及其改性过程中的反应情况。结果表明,改性后的EP制备出的树脂固化物具有良好的力学及耐热性能。     

丁腈橡胶增韧环氧树脂研究进展

综述了近年来丁腈类橡胶增韧环氧树脂的研究进展,其中包括固体丁腈橡胶,液体丁腈橡胶(丁腈-40液体橡胶,无规端羧基液体丁腈橡胶(CRBN),端羧基液体丁腈橡胶(CTBN),改性端羟基丁腈橡胶(HTBN),改性端氨基液体丁腈橡胶(ATBN))以及改性液体丁腈橡胶与纳米SiO2共同增韧环氧树脂。