不同粒径聚丙烯酸酯乳液的制备及共混物压敏特性

The Synthesis and Pressure Sensitive Adhesive Properties of Acrylic Copolymer Latexes with Different Particle Sizes

通过改变种子阶段乳化剂用量,采用半连续乳液聚合方法制备了不同粒径的丙烯酸酯共聚物乳液,随着乳化剂用量的增加,乳胶粒径明显变小,乳液黏度迅速增大;而对乳液聚合过程几乎没有影响,乳胶粒球形生长,二次成核粒子很少。将不同粒径的单分散乳液共混,利用动态机械热分析仪(DMA)表征共混物的分子运动,并依据FINAT标准测试了干燥后共混乳液的初粘力、剥离力和持粘强度。随着小粒径乳胶粒的加入,双组分丙烯酸酯共混物的初粘力增加,持粘强度降低;而三组分共混物乳液的性能受不同粒径乳液含量的影响,剥离力呈现下降的趋势。

A series of acrylic copolymer latexes with different particle sizes and distribution were prepared by semi-continuous emulsion polymerization.Dynamic light scattering（DLS） was used to monitor the particle diameters,which shows that the particles have grown without significant secondary nucleation.The particle size of the latexes has decreased and the dynamic viscosity of the latexes has increased with the growing content of the surfactant at the seed stage.Dynamic mechanical analysis was used to characterize the molecular movement of the copolymers.Adhesive properties measured are loop tack force,peel strength and shear resistance according to FINAT test methods.For the two component latex system,the loop tack increases with the addition of small particle size latexes,while the shear strength decreases.For the three component latex,the peel force decreases.