PP/LDPE化学交联发泡的研究

The study of the chemical crosslinked and foamed PP/LDPE

聚丙烯(PP)熔融黏度较低,发泡过程中气泡容易从熔体中溢出。在PP中加入低密度聚乙烯(LDPE)和偶氮二异丙苯(DCP),提高PP交联度,从而大大提高PP的熔融黏度。研究了共混聚合物组分的种类和含量对PP交联度的影响。结果表明,在共混过程中,部分PP和LDPE分子在热作用下相互促进,产生了接枝交联;共混物比纯PP的泡孔结构优且发泡效果佳,当LDPE为70%,发泡剂为5%,DCP为0.36%时,PP的发泡效果最好。解决了PP发泡过程中出现的气孔塌陷现象。

Since the melt viscosity of PP is lower than others, bubble is more easily escaping from the fon- dant during the foamed process. In order to enhance the degree of cross-linking of PP,low-density polyeth- ylene （LDPE） and DCP are added into the PP materials. The melt viscosity of PP increased significantly by this means. The influence of the type and content of the components of the polymer blend on the degree of the cross-linking of PP was discussed. The results showed that the crosslinking structure was produced by the reaction of PP and LDPE under the heat condition during the blending process. Blends had better foaming structure and showed better foaming effect than pure PP. PP showed the best effect of foaming when the amount of LDPE is 70% ,the amount of foaming agent is 5% ,the amount of DCP is 0.36%. Solving the pores collapse phenomenon in PP foaming process.