Abstract：Hexa (imidazolyl) cyclotriphosphazene (HImCP) was synthesized by nucleophilic substitution reaction of hexachlorocyclotriphosphazene with imidazole. The chemical structure was characterized by FT-IR,1H-NMR, and 31P-NMR. Then the as-prepared HImCP was utilized as curing catalyst for curing of diglycidylether of bisphenol A(E51)with methylhexahydrophthalic anhydride(MHHPA). Its influence on the storage stability at room temperature and curing activity at high temperature of E51/MHHPA system was studied by gelatum time and non-isothermal DSC analysis. The mechanical performance,glass-transition temperature(Tg),and thermostability of the obtained epoxy thermosets were also investigated. The results show that HImCP is a good latent curing catalyst contrast with unmodified imidazole. When the epoxy resin curing system contains 1% (mass fraction) of HImCP,it exhibits improved storage stability at room temperature as compared to that containing imidazole,as well as satisfied curing activity at high temperature. In addition,the obtained thermoset has higher tensile strength,Tg and thermostability than that resulted from imidazole.
张博文, 唐禹尧, 崔玉青, 魏玮, 李小杰, 罗静, 刘晓亚. 六咪唑环三磷腈的合成及其作为环氧树脂固化促进剂的性能[J]. 材料工程, 2019, 47(1): 91-96.
ZHANG Bo-wen, TANG Yu-yao, CUI Yu-qing, WEI Wei, LI Xiao-jie, LUO Jing, LIU Xiao-ya. Synthesis of hexa (imidazolyl) cyclotriphosphazene and its performance as curing catalyst of epoxy resin. Journal of Materials Engineering, 2019, 47(1): 91-96.
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