Z-N催化剂用于原位合成球形聚1-丁烯/聚丙烯合金

In-situ synthesis of spherical PB/PP alloy with Ziegler-Natta catalyst

采用球形Ziegler-Natta催化剂,通过原位聚合法制备了聚1-丁烯(PB)/聚丙烯(PP)合金,考察了聚合时间对聚合物形态、结构及性能的影响,并通过差示扫描量热法、扫描电子显微镜、X射线衍射等对合金的形态和物性进行了表征。结果表明:与1-丁烯本体聚合相比,原位聚合可改善PB的形态,有效地降低PB粒子间的粘连,使PB在釜内成为球形颗粒;丙烯聚合时间为40 min时,催化剂活性最高,达11.7 kg/g,PB/PP合金粉料的堆密度为0.44 g/cm3;原位聚合可有效地缩短PB由不稳定晶型Ⅱ向稳定晶型Ⅰ转变的周期。

Poly(1-butene)(PB)/polypropylene(PP)alloy was prepared via in-situ polymerization with spherical Ziegler-Natta catalyst.The effects of the polymerization time on the morphology,structure and properties of the polymers were investigated.The alloy obtained was characterized by means of differential scanning calorimeter,scanning electron microscope and X-ray diffraction.The results indicate that in-situ polymerization can improve the morphology of PB compared with the bulk polymerization of butene-1,it reduces the adhesion between polymer particles and helps to form spherical particles in the reactor.The catalytic activity reaches the highest of11.7kg/g and the bulk density of the alloy is0.45g/cm3when the polymerization continues for40minutes.Moreover,in-situ polymerization can effectively shorten the transition period of PB from the unstable crystalline formⅡto the stable formⅠ.