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Use of rare earth coordination catalyst for ethylene oxide and propylene oxide copolymerization

✍ Scribed by Zhiquan Shen; Jian Wu; Guoping Wang

Publisher
John Wiley and Sons
Year
1990
Tongue
English
Weight
315 KB
Volume
28
Category
Article
ISSN
0887-624X

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✦ Synopsis

Abstract

Neodymium tris(2‐ethylhexylphosphonate)‐triisobutylaluminum‐water system was investigated as a catalyst in ethylene oxide and propylene oxide copolymerization. Random copolymers of ethylene oxide and propylene oxide were obtained with high yield and high molecular weight in a short reaction time. The reactivity ratios of r~1~(EO) = 1.60 ± 0.04, r~2~(PO) = 0.45 ± 0.02 were determined. It was found that poly(propylene oxide) prepared with this catalyst system could initiate additional propylene oxide or ethylene oxide to form poly(propylene oxide) with higher molecular weight or propylene oxide‐ethylene oxide diblock copolymer. The microstructures of copolymers were studied by ^13^C‐NMR spectroscopy.

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