薄壁注塑透明聚丙烯专用料的结构与性能分析

Structure and performance analysis of transparent polypropylene special material for thin⁃wall injection molding

对市场上常见的4种薄壁注塑透明聚丙烯专用料的熔融结晶性能、光学性能、分子量分布、力学性能、毛细管流变性能、热收缩性能等进行对比分析。结果表明,K4860H与其他3种透明聚丙烯专用料相比分子量分布最窄;K4860H相对于其他3种透明聚丙烯专用料具有更好的韧性和透明性;相对其他2种透明聚丙烯,K4860H和MT45S具有更高的结晶温度和更快的结晶速率,表明其具有更为优良的结晶能力;4种透明聚丙烯样品的黏度随剪切速率的变化规律相同,表明其具有相同的加工流变性能;K4860H和500B 2个方向的模塑收缩率接近,说明其具有良好的尺寸稳定性;基于以上对比分析可知K4860H主要性能指标优于对比的3种聚丙烯专用料。

This paper reported an investigation on the melt crystallization properties,optical properties,molecular weight distribution,mechanical properties,capillary rheological properties,and thermal shrinkage properties of four types of transparent polypropylene(PP)specialized for injection molding.The results indicated that the K4860H‑type PP pre‑sented a narrower molecular weight distribution,better toughness,and a higher transparency degree than the other three types of PP.The K4860H‑type and MT45S‑type PP exhibited higher crystallization temperatures and faster crystalliza‑tion rates than the other two types of PP,representing a better crystallization capability.Moreover,the K4860H‑type PP showed a similar molding shrinkage to the 500B‑type one,indicating a good dimensional stability for thin‑wall injec‑tion molding.Based on the above analysis,the main performance of the K4860H‑type PP is superior to that of the other three types of PP.