Chen Chien-Han, Lee Kuan-Wei, Lin Ching-Hsuan, Ho Ming-Jaan, Hsu Mao-Feng, Hsiang Shou-Jui, Huang Nan-Kun, Juang Tzong-Yuan
Department of Chemical Engineering, National Chung Hsing University, Taichung 402, Taiwan.
Zhen Ding Technology Holding Limited, Taoyuan 33754, Taiwan.
Polymers (Basel). 2017 Dec 25;10(1):27. doi: 10.3390/polym10010027.
Three methacrylate-containing polyimides (Px⁻MMA; x = 1⁻3) were prepared from the esterification of hydroxyl-containing polyimides (Px⁻OH; x = 1⁻3) with methacrylic anhydride. Px⁻MMA exhibits active ester linkages (Ph⁻O⁻C(=O)⁻) that can react with epoxy in the presence of 4-dimethylaminopyridine (DMAP), so Px⁻MMA acted as a curing agent for a dicyclopentadiene-phenol epoxy (HP7200) to prepare epoxy thermosets (Px⁻MMA/HP7200; x = 1⁻3) thermosets. For property comparisons, P1⁻OH/HP7200 thermosets were also prepared. The reaction between active ester and epoxy results in an ester linkage, which is less polar than secondary alcohol resulting from the reaction between phenolic OH and epoxy, so P1⁻MMA/HP7200 are more hydrophobic and exhibit better dielectric properties than P1⁻OH/HP7200. The double bond of methacrylate can cure at higher temperatures, leading to epoxy thermosets with a high- and moderate-to-low dielectric properties.
通过含羟基聚酰亚胺(Px⁻OH;x = 1⁻3)与甲基丙烯酸酐的酯化反应制备了三种含甲基丙烯酸酯的聚酰亚胺(Px⁻MMA;x = 1⁻3)。Px⁻MMA具有活性酯键(Ph⁻O⁻C(=O)⁻),在4-二甲基氨基吡啶(DMAP)存在下能与环氧树脂反应,因此Px⁻MMA用作二环戊二烯-酚醛环氧树脂(HP7200)的固化剂,以制备环氧热固性材料(Px⁻MMA/HP7200;x = 1⁻3)热固性材料。为了进行性能比较,还制备了P1⁻OH/HP7200热固性材料。活性酯与环氧树脂之间的反应会生成酯键,该酯键的极性小于酚羟基与环氧树脂反应生成的仲醇,因此P1⁻MMA/HP7200比P1⁻OH/HP7200更疏水,并且具有更好的介电性能。甲基丙烯酸酯的双键可以在较高温度下固化,从而得到具有高介电性能和中低介电性能的环氧热固性材料。