橡胶粒子和刚性纳米粒子对注塑级硬质聚氯乙烯复合材料断裂行为的影响  

EFFECT OF RUBBER AND INORGANIC RIGID PARTICLES ON FRACTURE BEHAVIOR OF INJECTION-MOLDED PVC NANOCOMPOSITES

作　　者：都佩华[1,2,3] 于杰[3] 林鹏飞[1,2] 宋义虎 郑强[1,2,3] 

机构地区：[1]浙江大学高分子合成与功能构造教育部重点实验室 [2]浙江大学高分子科学与工程学系,杭州310027 [3]国家复合改性聚合物材料工程技术研究中心,贵阳550014

出　　处：《高分子学报》2011年第12期1395-1401,共7页Acta Polymerica Sinica

基　　金：国家科技支撑计划(项目号007BAE10B04)资助

摘　　要：采用核壳型丙烯腈-苯乙烯-丁二烯共聚物(ABS)和纳米碳酸钙(CaCO3)协同改性聚氯乙烯(PVC),制备了注塑级硬质PVC纳米复合材料.通过透射电镜(TEM)、扫描电镜(SEM)、力学性能测试研究了其结构与性能,并采用有限元模拟方法研究了ABS与纳米CaCO3粒子对复合材料断裂行为的影响.当CaCO3含量低于12 phr时,ABS和纳米CaCO3粒子在PVC基体中分散均匀,可起协同增韧作用.在外力作用下,ABS粒子形变主要以内空化方式进行.CaCO3未发生团聚时,CaCO3与PVC基体界面在外力作用下形成微孔;CaCO3发生团聚时,CaCO3与PVC基体界面处形成较大的裂纹.有限元分析结果表明,未发生团聚时,CaCO3和ABS粒子均可提高PVC基体的局部内应力,促使材料发生局部塑性屈服,导致复合材料屈服强度降低、冲击强度提高.ABS particles with core-shell structure and nano-CaCO3 particles were employed to modify hard PVC simultaneously.The phase morphology and fracture behavior of the composites were investigated by means of transmission electron microscope（TEM）,scanning electron microscope（SEM） and mechanical tests.Based on reasonable assumptions and material parameters obtained by the true stress-strain curve,finite element simulation employing the two-dimensional representative volume element model was carried out to explore the effects of ABS and CaCO3 particles on the fracture behavior of the composites.Results showed that ABS and CaCO3 particles have a synergistic toughening effect at nano-CaCO3 contents lower than 12 phr.The TEM observation revealed that the ABS particles deformed mainly by cavitation rather than interfacial debonding.The finite element analysis（FEA） results indicated that the blend yields when local yielding areas in the matrix begin to interconnect throughout the interstitial matrix between the particles.The predicted yield stresses for the PVC/ABS binary blend and the PVC/ABS/nano-CaCO3 ternary composite are consistent with experimental values.Moreover,the FEA results implied that both ABS and CaCO3 particles could toughen the PVC matrix,and the well-dispersed CaCO3 particles had a better toughening effect.If the CaCO3 particles are agglomerated,however,the large crevices between CaCO3 agglomerates and PVC matrix would initiate cracks at the interface and lead to decrease of mechanical properties.

关 键 词：聚氯乙烯 纳米复合材料 断裂 有限元分析 

分 类 号：TQ325.3[化学工程—合成树脂塑料工业]