反应挤出共混法制备发泡用聚丙烯的研究  

High-Melt-Viscosity Polypropylene for Foaming Prepared by Reactive Extrusion Blending Method

作　　者：杨淑静[1] 宋国君[1] 杨超[1] 江峰[1] 

机构地区：[1]青岛大学化工学院,山东青岛266071

出　　处：《塑料》2006年第3期73-77,共5页Plastics

摘　　要：采用反应型双螺杆挤出机,以过氧化苯甲酰(BPO)做引发剂,不饱和烯烃为交联助剂,一步实现聚丙烯(PP)与少量低密度聚乙烯(LDPE)的共混、接枝与交联,制备出了具有高熔体黏度的发泡用聚丙烯。研究结果表明,改性后PP的熔体流动速率(MFR)可降至0.1 g/10m in以下,体系中有质量含量高达48%以上的凝胶产生,当交联助剂含量与引发剂含量的质量比例约为1.3∶1时,可以获得最佳的改性效果。体系中的引发剂和交联助剂均显著影响改性材料的熔体流动性和凝胶含量,在引发剂质量含量达到0.8%以上时,MFR和凝胶含量变化趋势减缓;差示扫描量热分析(DSC)研究表明,交联使体系中PP相和PE相的结晶速率都下降。对改性后的样品进行发泡实验,结果表明采用反应共混改性PP可获得泡孔细密均匀、穿孔很少的高质量泡沫塑料。A high-melt-viscosity modified polypropylene （PP） for foaming was prepared by blending copolymerized PP （CPP） with low-density polyethylene （LDPE） through reactive extrusion. The crosslinking was initiated and promoted in the system using henzyl peroxide （BPO） as initiator and unsaturated olefin as crosslinking coagent. The result showed that after modifying,MFR decreased to below 0. 1 g/10min and gel content was above 48 wt% , and the optimal effect was achieved when the weight ratio of the coagent to the initiator was 1.3： 1. The content of initiator and coagent in the formulation influenced the melt fluidity of the modified PP significantly,and the change of MFR and gel content slowed down when initiator content was up to 0. 8 wt%. The result of thermal analysis by differential scanning calorimetry （DSC） indicated that crosslinking decreased both of the crystal rate of PP and PE in the system. High-quality foam with uniform, closed and independent cells were fabricated with the modified PP.

关 键 词：反应共混 聚丙烯/聚乙烯 熔体流动速率 凝胶含量 发泡 

分 类 号：TQ325.14[化学工程—合成树脂塑料工业]