内交联单体对水性双组份涂料性能的影响

The Effects of the inner cross-linking monomer on the properties of waterborne two components polyurethane coatings

摘要:

以三羟甲基丙烷三丙烯酸酯(TMPTA)为内交联单体，采用种子乳液聚合与交联单体分段滴加工艺合成羟基聚丙烯酸酯乳液（HPAE），配制水性双组份聚氨酯涂料(WB 2K-PUR)。考查了TMPTA的添加量及其在核、壳中的分布对乳液聚合稳定性和涂膜性能的影响。研究表明：当TMPTA添加量为2 wt% 时，乳液聚合稳定性好，凝胶率仅为0.26wt%；涂膜的综合性能好，包括涂膜具有0.78硬度、96.4%交联度和92%光泽度。热重分析（TGA）表明：TMPTA在核壳中以3:7的比例分布的HPA涂膜具有较好的热稳定性。

Abstract:

The hydroxyl polyacrylate emulsions (HPAE) for waterborne two-component polyurethane coatings (WB 2K-PUR) were synthesized by semi-continuous seeded emulsion polymerizations with trihydroxymethyl propane triacrylate (TMPTA) used as an inner cross-linking agent added by multi-stage. The effects of the TMPTA amounts and distributions in core/shell parts of latexes on the emulsion polymerization stability and the film properties were studied. The results indicated that the WB 2K-PUR film with 2 wt% TMPTA displays excellent physical-chemical properties including 0.78 of hardness, 96.4% of cross-linkage degree and 92% of gloss, besides good emulsion polymerization stability with 0.26% of coagulation contents. TGA curves indicated that WB 2K-PUR film with 3:7 of the TMPTA distribution ratio in the core and shell parts exhibits good thermal stability.