核壳式纳米Al_2O_3/PS复合粒子的表征及增韧选区激光烧结聚苯乙烯的研究

Study on Characterization of Core-shell Nano-Al_2O_3/PS Composite Particles and Toughening Polystyrene Prepared by SLS

运用TEM,FTIR对乳液聚合方法制备纳米Al2O3/PS复合粒子结构进行了表征,结果表明,制备出的复合粒子具备以纳米氧化铝为核、以聚苯乙烯为壳的核壳式结构;并将核壳式复合粒子用来增韧选区激光烧结聚苯乙烯,结果发现,其缺口冲击强度达到12.1kJ/m2,较纯聚苯乙烯提高了50%左右,比添加未经任何改性处理纳米氧化铝粒子的复合材料提高了30%;利用FE-SEM对试件的冲击断面进行了微观结构分析,结果表明:核壳式纳米Al2O3/PS复合粒子改善了纳米粒子与基体表面极性的差异,增强了其与聚合物基体之间的界面相容性,从而改性了选区激光烧结制备聚苯乙烯基复合材料,并很好地起到增韧的效果。

Surface of nano-Al2O3 particle was covered with PS by emulsion polymerization to prevent the reunion. The structure of emulsion polymeric Al2O3/PS composite particle was characterized by TEM and FTIR. The results indicate that the composite particles are approximate ball shape and the particle consists of centered core（Al2O3） and outer shell（PS）. The composite particles were used as fillers to toughen PS based composites prepared by selective laser sintering （SLS）. It was founded the notched impact strength of treated composites increased 50% than that of unfilled PS and increased 30% than that of untreated composites, the maximum value was 12. 1kJ/m^2; FE-SEM studied the tensile fracture surfaces of the sintered specimens. It was noted the fracture surfaces of composites with treated nanoparticles were rougher than those of unfilled PS and those of the untreated composite, and the interracial compatibility and adhesion property are improved, which toughened PS prepared by SLS well.