【作者】 孔德娟；

【导师】 高俊刚；

【作者基本信息】 河北大学 ， 高分子化学与物理， 2009， 硕士

【摘要】 本文目的在于合成低成本的环氧基和胺基-笼型倍半硅氧烷(POSS)单体,然后制备成含有笼型倍半硅氧烷的有机-无机纳米杂化材料,探讨其形成原理、组成、结构和性能等方面之间的关系。本文通过LC/MS、DSC、TBA、TG和x-射线能谱仪等对笼型倍半硅氧烷的结构进行了表征,研究了POSS/环氧树脂杂化体系的固化动力学和热性能。主要包括以下几个方面：(1)通过水解缩聚法合成八聚体r-环氧丙氧丙基笼型倍半硅氧烷G-POSS,以甲基四氢苯酐为固化剂(MeTHPA),与双酚-A环氧树脂(BPAER)制备成不同配比的有机/无机杂化材料,探讨了G-POSS加入量对G-POSS/BPAER/MeTHPA杂化树脂的固化行为和热性能的影响。研究结果表明：G-POSS与BPAER相容性较好,可共同固化；其非等温固化行为适用于Sestak-Berggren自催化模型,分析讨论了固化反应机理,证明改性后环氧树脂的耐热性有显著提高。(2)为降低G-POSS环氧树脂的官能度,合成了含有部分甲基的笼型倍半硅氧烷环氧树脂(GM-POSS)。用DSC,TG,TBA和x-射线能谱仪研究了GM-POSS/双酚-A环氧共混物与甲基四氢苯酐(MeTHPA)的固化过程及热性能。结果表明固化反应的平均活化能Ea随GM-POSS含量的增加呈现先降低后增加的趋势；固化树脂的玻璃化转变温度、热分解温度及热残余量均随GM-POSS加入量的增加而提高；热降解动力学分析表明,杂化树脂的分解主要分两步进行,且均服从一级反应动力学。(3)合成了笼型β-氨乙基-γ-氨丙基倍半硅氧烷(POAAS),并以此固化邻甲酚醛环氧树脂(o-CFER),制备成不同配比的纳米复合材料,探讨了其固化行为、热性能、力学性能及介电性能。研究结果表明平均活化能为58.42kJ/mol,固化反应遵循Sestak-Berggren自催化模型,Tg随POAAS含量的增加呈现先增加后降低的趋势,当N=0.50时,Tg达最大值为107℃,层压板材料具有更高的拉伸强度、冲击强度和良好的介电性能。更多还原

【Abstract】 In order to obtain the hybrid polymeric composites with more excellent useful performance, In this paper, the Epoxy-POSS and NH2-POSS were used as modifiers and prepared the POSS-containing nanocomposites of epoxy resin. The relationships of structure-property, cure kinetics and thermal properties of the POSS/epoxy system were investigated. The main work as follow:(1)Polyhedral oligomeric silsesquioxanes epoxy resin (G-POSS) was prepared from 3-glycidyloxypropyl-trimethoxysilane (GTMS) by hydrolytic condensation. The co-cure kinetics and thermal properties of G-POSS with bisphenol-A epoxy resin (BPAER) using 3-methyl-tetrahydrophthalic anhydride (MeTHPA) as curing agent were investigated. The results showed that the compatibility of G-POSS with BPAER was well and can co-cure.These curing reactions can be described by the Sestak-Berggren (S-B) autocatalytic model, and the curing mechanism of epoxy/MeTHPA system was proposed. TGA and TBA analysis results showed that the heat-resistance of the hybrid nanocomposites was effectively improved.(2) In order to decrease the functional group density of G-POSS,a novel POSS including some amount of methyl groups i.e. GM-POSS was synthesized. Bisphenol-A epoxy resin was modified by GM-POSS used MeTHPA as curing agent to prepare organic-inorganic hybrid resin, the cure kinetics and thermal properties of which were investigated by non-isothermal differential scanning calorimetry (DSC), TGA, TBA and X-ray energy dispersive spectrometry (EDS).The results indicated that the average activation energy increased first, then decreased with the GM-POSS content increasing, the thermal decomposition temperature, thermal residue and glass transition temperature Tg of the hybrid resins were remarkably improved with the content of GM-POSS increasing. The kinetics of thermal degradation was also investigated and the results showed that the thermal degradation process can be divided into two stages and both of them follow the first order kinetics.(3)Polyhedral oligomeric (β-aminoethyl-y-amino propyl)silsesquioxane (POAAS) was synthesized and the hybrid nanocomposites of POAAS with o-cresol formaldehyde epoxy resin (o-CFER) were prepared. The cure kinetics, thermal, mechanical and dielectric properties were investigated with DSC, scanning electron microscopy (SEM), TGA, TBA, tensile tester, impact tester and electric analyzer, respectively. The results showed that the average Ea was 58.42 kJ/mol, and the curing reactions well obeyed for the Sestak-Berggren (S-B) autocatalytic model. The Tg increased with the content of POAAS first, and had a maximal value of 107℃at N=0.50, then decreased modestly. The tensile and impact tests of the fiberglass-reinforced laminate indicated that POAAS could reinforce the mechanical properties and electric properties of epoxy resin effectively.更多还原