Prof. Lianfang FENG's Group

      我组博士生田洲撰写的论文《Periodic Switching of Monomer Additions for Controlling the Compositions and Microstructures of Segmented and Random Ethylene-Propylene Copolymers in Polypropylene in-Reactor Alloys》在化学工程国际权威期刊Industrial & Engineering Chemistry Research上发表。该工作旨在剖析Basell公司最新的多区循环反应器的技术原理，创新建立多功能气氛切换聚合装置。设计周期性单体切换进料策略制备了具有优良刚-韧平衡性能的抗冲聚丙烯共聚物，初步揭示了多区循环工艺特性影响原位橡塑合金组成与微结构的规律。

ABSTRACT: This work aims at shading fundamental insights into mechanisms that dictate the composition and microstructure of polypropylene/poly(ethylene-co-propylene) (PP/EPR) in-reactor alloys produced by the multizone circulating reactor (MZCR) technology, a novel one for polyolefin production. For this purpose, this technology is simulated by a batch process with periodic switching of monomer additions. An increase in the switch frequency leads to a decrease in the fraction of ethylene/propylene random (amorphous) copolymers denoted as EPR and an increase in the fraction and the length of PP segments of ethylene/propylene segmented (partially crystalline) copolymers denoted as EPS. Concomitantly, the size of the dispersed phase domains (EPR) decreases, and its size distribution becomes more uniform as a result of the decrease in the fraction of the EPR and the increase in that of the EPS which acts as a compatibilizer for PP/EPR in-reactor blends. Mechanical properties of the PP/EPR in-reactor blends are also discussed. 

http://pubs.acs.org/doi/full/10.1021/ie102436u