过渡层结构对PVC/AIM复合材料性能的影响

Effect of transition layer on mechanical properties of PVC/AIM composite

采用种子乳液聚合法合成了具有不同过渡层结构的核壳丙烯酸酯类抗冲击改性剂(AIM),用于聚氯乙烯(PVC)树脂的增韧改性。使用动态激光粒度分析仪、差示扫描量热仪和动态黏弹谱仪等测试了AIM的粒子结构、尺寸和玻璃化转变温度,研究了PVC/AIM复合材料的力学性能与AIM的结构及用量的关系。AIM的过渡层结构对PVC/AIM复合体系的力学性能影响显著。以"递变进料"方式合成过渡层的AIM增韧效率最高,在m(PVC)/m(AIM)为100:7时,复合材料可实现韧性断裂,缺口冲击强度达1.121 kJ/m,是纯PVC的26倍;拉伸强度为49.9 MPa。

The authors synthesized a class of core-shell structured acrylic impact modifiers （AIM） possessing diverse transition layers via seeded emulsion polymerization, aiming at modifying toughness of polyvinyl chloride （PVC） resin. The size and structure of latex particles and glass transition temperature of AIM were investigated by means of dynamic laser scattering method, differential scanning calorimetry （DSC）and dynamic mechanical analysis. The dependence of mechanical properties of PVC/AIM composites on the structure of AIM particles and the content of AIM was explored. The results reveal that the transition layer of AIM influences remarkably the mechanical properties of PVC/AIM composites. The AIM with transition layer, which is synthesized in the ＂power feed＂ method, displays the highest toughening efficiency. When the mass ratio of PVC/AIM attains 100 ： 7, the composite has notch impact strength of 1.121 kJ/m, 26 times of that of pure PVC resin, and tensile strength of 49.9 MPa. Ductile rupture is supposed to occur when the composite with such mass ratio of PVC/ AIM cracks.