链转移剂加入方式对丙烯酸酯乳液聚合过程及压敏粘接性能的影响

Effect of the Charging Method of Chain-Transfer Agent on Emulsion Polymerization Process and Pressure-Sensitive Adhesive Properties

报道了三种不同链转移剂加料方式制备的丙烯酸丁酯共聚物乳液,其固含量为50%,并研究了它们的压敏特性。动态光散射跟踪了聚合过程乳胶粒粒径的变化,结果显示,该乳液聚合没有明显的二次成核过程,按预定的粒径生长。用凝胶渗透色谱(GPC)和动态力学分析(DMA)表征了聚合物的分子参数,按照FINAT标准测试了该乳液压敏胶的初粘力、剥离力和耐剪切强度,并将压敏性能与分子参数,如凝胶含量和聚合物分子量进行了关联。

The preparation of three kinds of poly（n-butyl acrylate-co-acrylic acid） latexes with different charging methods of ehain-transfer agent was reported, and investigations into the pressure-adhesive properties of the latexes were made. The latexes were prepared at a solid content of 50 % by a two-stage sequential emulsion polymerization with the monomers n-butyl acrylate （BA） and acrylic acid （AA）. Dynamie light scattering was used to monitor the particle diameters and showed that the particles grew without significant secondary nucleation occurring. The molecular parameters were characterized by gel permeation chromatography and dynamic mechanical analysis. The adhesive properties measured were loop tack force, peel strength and shear resistance according to FINAT test methods. The relationship between pressure-sensitive properties and molecular parameters, such as gel content and molecular weight, was evaluated.