以聚丙烯(PP)粉料为基料,将不同受阻酚类主抗氧剂(1010、1076和1330)分别与亚磷酸酯类辅抗氧剂(168)以不同质量比进行复配,通过熔融共混挤出方法制备了3种改性PP医用树脂,并研究了主/辅抗氧剂组成及其质量比对样品力学性能、光学性能、加工性能及抗氧化性能的影响。结果表明:3种改性PP的力学性能均达到药品包装材料标准要求,其中主/辅抗氧剂质量比分别为1∶2、1∶3、1∶3制备的改性PP具有良好的刚韧平衡性;3种改性PP的透光率均超过85%且差异小,但雾度差异明显;辅抗氧剂比例较高时,改性PP粒料黄色指数较小,其中抗氧剂1330/168改性PP粒料的黄色指数最小,为-0.29。3种改性PP的熔融指数和氧化诱导期(OIT)均随辅抗氧剂比例增加而减小,其中抗氧剂1010/168改性PP熔融指数最小且OIT最高,OIT达10.9min。

In this study,using different mass ratios of hindered phenolic primary antioxidants (1010,1076,and 1330) to a phosphite secondary antioxidant (168),three antioxidant systems (1010/168,1076/168and 1330/168) modified polypropylene (PP) medical resins were successfully prepared via melt blending and extrusion with PP powder as the base material.The effects of the primary/secondary antioxidant composition and mass ratios on the mechanical,optical,processing,and antioxidant properties of the modified PP were systematically investigated.The results demonstrated that all three modified PP medical resins met the standard requirements for pharmaceutical packaging materials in mechanical properties.Among them,the modified PP samples exhibited optimal balanced rigidity and toughness at the mass ratios of primary/secondary antioxidant of 1∶2,1∶3,and 1∶3.The light transmittance of all modified PP sheets exceeded 85% with minimal variations,while significant differences in haze were observed.The PP pellets had the less yellow index at higher proportions of secondary antioxidant,and the PP pellet modified with 1330/168 antioxidant system had minimum yellow index of -0.29.Both melt flow index (MFI) and oxidation induction time (OIT) of all three modified PP decreased with increasing secondary antioxidant content.The 1010/168 antioxidant system modified PP exhibited the lowest MFI,and the highest OIT,reaching 10.9min.