聚丙烯接枝马来酸酐改性纳米ZnO/聚丙烯复合材料的成核结晶行为及力学性能
Nucleation and crystallization and mechanical properties of nano-ZnO/polypropylene composites modified by maleic anhydride grafted polypropylene

采用熔融共混法制备了nano-ZnO/聚丙烯（PP）复合材料，研究了相容剂聚丙烯接枝马来酸酐（PP-g-MAH）的加入对nano-ZnO/PP复合材料的成核结晶行为、晶体结构、结晶形态以及力学性能的影响。结果表明，低添加量（质量分数小于5%）的nano-ZnO对PP有较好的β晶成核效应，而当其质量分数大于5%时，nano-ZnO对PP结晶有明显的异相成核作用，使PP结晶温度大幅度提高，PP结晶在（040）晶面呈现生长择优性；PP-g-MAH的加入增强了nano-ZnO粒子与PP基体之间的界面相互作用，改善了纳米粒子的分散性，促进了PP基体的异相成核，提高了nano-ZnO/PP复合材料的拉伸强度和冲击强度，但却抑制了nano-ZnO诱导PP生成β晶。nano-ZnO/PP复合材料体系中因界面相互作用改善所致的韧性提高明显强于nano-ZnO诱导PP形成β晶的增韧效应。 A series of nano-ZnO/polypropylene (PP) composites were prepared via melt blending. The effect of compatibilizer maleic anhydride grafted polypropylene (PP-g-MAH) on nucleation and crystallization behavior, crystal structure, morphology and mechanical properties of nano-ZnO/PP composites was investigated. The results show that nano-ZnO has good effect on the β-crystal nucleation of PP when nano-ZnO is added in low level (mass fraction less than 5%). When the mass fraction of nano-ZnO is more than 5%, nano-ZnO has obvious heterogeneous nucleation effect on PP matrix, with the cryatallization peak temperature of PP shifted to higher temperature significantly, and PP presents preferential growth in (040) crystal face. PP-g-MAH enhances the interfacial interaction between nano-ZnO particles and PP matrix, which improves the dispersion of nanoparticles, and promotes the heterogeneous nucleation of PP matrix. Consequently, the tensile strength and impact strength of nano-ZnO/PP composites are improved obviously. However, the ability of β-crystal induced by nano-ZnO is inhibited. The toughness of nano-ZnO/PP nanocomposites improved due to better interaction interface is significantly stronger than the β-crystal toughening effect induced by nano-ZnO. 江苏高校优势学科建设工程