含硅聚氨酯预聚体改性聚丙烯酸酯清漆的制备与研究

Preparation and Study of Acrylate Varnish Modified by Silica-containing PU Prepoplymer

采用端羟基聚硅氧烷、功能单体与异佛尔酮二异氰酸酯缩聚制备新型含硅聚氨酯预聚体(Si-PU),Si-PU与丙烯酸酯单体共聚,得到Si-PU改性聚丙烯酸酯。以改性聚丙烯酸酯为成膜物质,以异氰酸酯基树脂为固化剂按基团等物质的量比配制成双组分清漆,并制备涂膜。采用FT-IR对改性前后聚丙烯酸酯结构进行了表征。研究了Si-PU用量对聚丙烯酸酯清漆的黏度、耐热性、附着力及其涂膜绝缘性的影响。FT-IR表明,Si-PU已经接枝到了丙烯酸酯共聚物的骨架中。Si-PU质量分数在0～15%,涂膜的附着力不变,且Si-PU用量为聚丙烯酸酯的15%时,得到综合性能良好的含硅聚氨酯改性聚丙烯酸酯清漆。

Hdroxyl-terminated polysiloxane,functional monomer and isophorone diisocyanate are used to prepare new silicacontaining PU prepoplymer （Si-PU） through polycondensation;then through copolymerization of Si-PU and acrylate monomer,Si-PU modifing acrylate resin is obtained.The modified acrylate resin as film-forming substance,with isocyanate-based resin as curing agent in equal molar ratio is to give two-package varnish,then to give coatings film.FT-IR is used to characterize the structure of acrylate resin before and after modification,to study the in？ uence of Si-PU amount on viscosity,thermal resistance,adhesion and film insulation property,showing that Si-PU has been grafted onto the backbone of the acrylate copolymer;when the mass fraction of Si-PU is in 0～15%,the adhesion of the film remains unchanged and when it is 15%,the silica-containing PU modifying polyacrylate varnish is obtained with excellent comprehensive properties.