聚氨酯/聚丙烯酸酯混杂乳液的制备与性能研究

利用核／壳型乳液聚合技术制备了聚氨酯(PU)／聚丙烯酸酯(PA)混杂乳液,并通过动态粘弹谱仪、广角X光衍射仪、激光粒度仪等分析手段对其进行研究,探讨了不同共混方式、不同组成、不同NCO与OH摩尔比对其性能、形态结构以及两相相容性的影响。结果表明,由于两种聚合物之间的协同效应使得PU/PA混杂乳液的耐水性和机械性能比其对应的物理机械共混物有显著提高。当PA质量分数小于50％时,两相相容性良好。PU／PA混杂乳液中PA含量以及NCO与OH摩尔比将影响混杂乳液的粒径。当PA质量分数小于33％时,乳液的平均粒径几乎与作为种子的PU乳液粒径相同,但进一步增加PA含量,粒径急剧增大。同时,随着NCO与OH摩尔比的增加,其乳胶粒子尺寸增大。

Study on the Preparation and Properties of Polyurethane/Polyacrylate Hybrid latexes

Polyurethane (PU)/polyacrylate (PA) hybrid latexes were synthesized by core/shell latex polymerization technique. Structure and morphology of the hybrid latexes were characterized by DMA, WAXD and DLS. Influence of PU/PA mass ratio, blending method and NCO/OH mole ratio on properties, structure and morphology of hybrid latexes were investigated and discussed. PU/PA hybrid latexes had better water resistance and mechanical properties than those of physical polymer blends. When PA content in PU/PA hybrid latexes was less than 50 % , good compatibility between PU and PA component was observed. PA content and NCO/OH mole ratios in PU/PA hybrid latexes affected their particle size. When PA content of PU/PA hybrid latexes was less than 33% ,average particle size of PU/PA hybrid latexes was almost the same as PU latex. However,the average particle size increased remarkably with further increase in PA content. Particle size of PU/PA hybrid latexes increased with increasing NCO/OH mole ratio.