环氧树脂E-20改性有机钛硅树脂的制备

Preparation of titanium-doped silicone resins modified by epoxy resin E-20

在二月桂酸二丁基锡的催化作用下,用环氧树脂(E-20)与含钛的有机硅树脂缩聚合成了系列环氧改性有机钛硅树脂。通过红外光谱、羟值和相对分子质量分布的分析测定研究了改性树脂的固化活性、耐热性、附着力等。结果表明:以钛酸四正丁酯为固化剂的改性树脂具有高固化活性;在100℃下涂膜的固化时间小于或等于10min;当E-20和有机钛硅树脂的质量比为1.0∶1.0时,固化膜附着力达1级,铅笔硬度达3H,冲击力大于50 kg.cm;改性树脂可耐450～500℃的高温,固化膜在500℃高温下烘烤3 h,涂层基本没有裂纹和脱落现象。

A series of epoxy modified titanium-doped silicone resins were prepared with dibutyhin dilaurate as catalyst via polycondensation of epoxy resin E-20 and titanium-contained silicone resins. The curing activity, thermal stability, adhesion and mechanical properties of the modified resins were studied by means of infrared spectrometry, hydroxyl value and relative molecular mass distribution analysis. The results show that the modified resins have high curing activity in the case of using tetra-n-butyltitanate as curing agent. The curing time of the film coating at 100 ℃ is less than or equal to 10 min. When the mass ratio of epoxy resin E-20 to titaniumcontained silicone resins is 1：1, the adhesion and pencil hardness of the cured film reaches level 1 and 3 H, respectively, and the impact resistance of the film is more than 50 kg＇cm. The modified resins can resist service temperature of 450-500 ℃, and there exists no cracking and falling off phenomenon on the coating layer of the film after being baked at 500℃ for 3 h.