分子筛协同有机磷酸盐改性聚丙烯性能的研究

采用直接混合法制得等规聚丙烯(iPP)/分子筛体系和iPP/有机磷酸盐成核剂(NA11)/分子筛体系,研究不同种类分子筛在不同含量下对iPP结晶温度及力学性能的影响,进而研究不同分子筛在低含量下协同有机磷酸盐对iPP体系成核性能的影响,从动力学角度解释了提升原因。结果表明,单独添加分子筛制得的iPP体系,随着分子筛含量的增加,结晶性能和力学性能得到显著提升,不同分子筛对iPP性能的影响不同,ZSM-5型分子筛在含量为5%(质量分数,下同)以上具有促进iPPβ晶型生成的效果;采用直接混合法制得的不同分子筛复配有机磷酸酯钠盐NA11成核剂可提升iPP的力学性能;特别是当0.1%NA11和0.1%4A型分子筛一起添加到iPP中时,可在保证iPP具有较好刚性的同时兼具有良好的韧性,使iPP的弯曲模量提高35.2%、冲击强度提高14.4%,从而达到促进iPP材料刚韧平衡的效果。

Study on Properties of Polypropylene Modified with Combination of Zeolites and Organic Phosphate Salt

Isotactic polypropylene(iPP)/zeolite and iPP/phosphate sodium nucleating agent(NA11)/zeolite compounds were prepared by a direct mixing method,and the effects of the type and content of zeolite on their crystallization temperature and mechanical properties were investigated.Furthermore,the synergistic effect from zeolite and organophosphates on the nucleation performance of the compounds was studied,and a kinetic analysis was performed for the crystalline improvement of iPP.The results indicated that the addition of zeolite improved the crystallization and mechanical properties of iPP significantly,and the type of zeolite was found to influence the performance of iPP.The ZSM-5-type zeolite could promote the formation ofβ-form crystal of iPP at the concentration over 5 wt%.The combination of zeolite and NA11 could further improve the mechanical properties of the compounds,and good rigidity and toughness were achieved for the compounds containing 0.1 wt%NA11 and 0.1 wt%4 A-type zeolite.The compounds gained an increase in flexural modulus by 35.2%and in impact strength by 14.4%compared to pure iPP,indicating a good balance between rigidity and toughness.