私密直播全婐app免费大渔直播,国产av成人无码免费视频,男女同房做爰全过程高潮,国产精品自产拍在线观看

Links
Contact Info.
  • Address:加拿大魁北克省蒙特利爾
  • Zip:無
  • Tel:(514) 848-2424 ext.5611
  • Fax:
  • Email:zhibin.ye@concordia.ca
Current Location :> Home > Publications > Text
Synthesis of branched polypropylene with isotactic backbone and atactic side chains by binary iron and zirconium single site catalysts
writer:Z. Ye, S. Zhu*
keywords:Binary catalyst system, Single-site-type catalysts, Tandem action, Propylene polymerization, Branched, High-impact poly(propylene) (PP)
source:期刊
specific source:Journal of Polymer Science, Part A, Polymer Chemistry
Issue time:2003年
This article reports the use of a binary single‐site catalyst system for synthesizing comb‐branched polypropylene samples having isotactic polypropylene (iPP) backbones and atactic polypropylene (aPP) side chains from propylene feedstock. This catalyst system consisted of the bisiminepyridine iron catalyst {[2-ArN?C(Me)]2C5H3N}FeCl2 [Ar=2,6-C6H3(Me)2] (1) and the zirconocene catalyst rac-Me2Si(2-MeBenz[e]Ind)2ZrCl2 (2). The former in situ generated 1-propenyl‐ended aPP macromonomer, whereas the latter incorporated the macromonomer into the copolymer. The effects of reaction conditions, such as the catalyst addition procedure and the ratio of 1/2 on the branching frequency, were examined. Copolymer samples having a branching density up to 8.6 aPP side chains per 1000 iPP monomer units were obtained. The branched copolymers were characterized by 13C NMR and differential scanning calorimetry.