| 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.
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