正离子光固化聚硅氧烷的合成及其环氧树脂复合固化膜的性能

SYNTHESIS OF CATIONIC UV-CURABLE POLYSILOXANES AND PROPERTIES OF THE CURED FILMS OF THEIR COMPOSITES WITH EPOXY RESIN

以含氢聚硅氧烷(PMHS)分别与甲基丙烯酸六氟丁酯(HFMA)和烯丙基缩水甘油醚(AGE),经氯铂酸催化硅氢加成反应将甲基丙烯酸六氟丁酯和烯丙基缩水甘油醚引入聚硅氧烷的侧链,合成了3种含氟量不同的含氟代烃侧基/环氧侧基聚硅氧烷(EFPS),用FTIR、1H-NMR和13C-NMR进行了结构表征,将这类聚硅氧烷与环氧树脂E51复合经正离子光交联反应后制得固化膜,并研究了所得固化膜的热性能、表面性能、吸水性能.研究结果表明,侧链中引入正离子光敏性基团提高了聚硅氧烷与环氧树脂复合组分的交联程度,氟和硅的存在使加入该含氟聚硅氧烷的环氧树脂固化膜的T5%和T50%分别高达337.7℃和463.6℃,600℃处热失重残留率提高到25.6%,表面能从44.1 mJ/m2下降到15.3 mJ/m2,吸水率小于0.5%.经截面微观形貌分析,该聚硅氧烷与环氧树脂呈现部分相容.

By means of a platinum-catalyzed hydrosilylation reaction,2,2,3,4,4,4-hexafluorobutyl methacrylate（HFMA） and allyl glycidyl ether（AGE） in different proportions were used to react with polymethylhydrosiloxane（PMHS） in turn,then with different fluorine contents,three kinds of cationic UV-curable polysiloxanes containing fluorinated/epoxy side groups（EFPS） were obtained.Their chemical structures were characterized by FTIR,1H-NMR and 13C-NMR.By respectively mixing the three synthesized polysiloxanes with a selected UV-curable epoxy resin（E51）,a series of cured composite films were prepared via cationic photopolymerization under UV irradiation.The thermal stability,surface energy and water resistance property of these cured composite films were analyzed by means of TGA,surface contact angle test and water absorption ratio test.The results indicated that after the introduction of the cationic UV-curable epoxy groups into the side chains of PMHS,the obtained EFPS had more crosslinkable groups,leading to relatively high crosslink degree between the EFPS and the selected epoxy resin.When a quantity of the EFPS was added into epoxy resin matrix,in the presence of fluorine and silicon,the temperature values of the 5% mass loss（T5%） and the 50% mass loss（T50%） of the cured composite films increased to 337.7℃ and 463.6℃,respectively,and their residual weight at 600℃ increased to 25.6%.The calculated surface energy values of the cured films decreased from 44.1 mJ/m2 to 15.3 mJ/m2,and the water absorption ratios were lower than 0.5%.By scanning electron microscopy measurements,the cross-section morphology of the cured composite films showed that the EFPS and the selected epoxy resin was compatible.