纳米SiO_2对聚丙烯酸酯乳液压敏胶性能的影响

Influence of nano-SiO_2 on properties of polyacrylate emulsion pressure sensitive adhesives

采用原位乳液聚合法成功制备了聚丙烯酸酯/纳米SiO2复合压敏胶乳液。纳米SiO2无需表面处理,即能有效地被分散成初始粒子状态,并在纳米尺度上与原位生成的聚丙烯酸酯复合。SiO2因界面作用富集于乳胶粒子的表面,使整个粒子具有类似于“草莓”般的形貌。纳米SiO2可显著改善聚丙烯酸酯胶膜的流变性能和压敏性能,除初黏会略微下降外,持黏和180°剥离强度可同时提高,其中180°剥离强度能提高到30%以上。

Polyacrylate/nano-SiO2 composite emulsions used as pressure sensitive adhesives have been successfully prepared via in-situ emulsion polymerization. Although the surface of nano-SiO2 was not organically modified , it was discovered through transmission electron microscope that SiO2 particles can be availably dispersed to primary structure and can participated in the composite reaction with polyacrylate on nanometer scale. It was clearly observed that SiO2 nanoparticles were embedded within the polymer latex particles, which exhibited a distinctive raspberry morpaology, It was also confirmed that composite emulsions behave better pressure sensitive properties. In addition to slight reducement of tack, hold strength was improved, and peel strength was remarkedly enhanced by 30%.