Premium
Molecular Weight Distribution in Ring‐Opening Polymerization of Propylene Oxide Catalyzed by Double Metal Complex: A Model Simulation
Author(s) -
Zhao Jing,
Li BoGeng,
Fan Hong
Publication year - 2021
Publication title -
macromolecular theory and simulations
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.37
H-Index - 56
eISSN - 1521-3919
pISSN - 1022-1344
DOI - 10.1002/mats.202000101
Subject(s) - monomer , dispersity , polymerization , molar mass distribution , propylene oxide , chain transfer , chemistry , polymer chemistry , catalysis , polypropylene glycol , reaction rate constant , polyvinyl alcohol , radical polymerization , polymer , kinetics , ethylene oxide , organic chemistry , polyethylene glycol , copolymer , physics , quantum mechanics
In the present work, method of moments is used to model the molecular weight distribution (MWD) of polypropylene glycol (PPG) produced with ring‐opening polymerization of propylene oxide catalyzed by double metal complex (DMC), and an explicit expression about the polydispersity index (PDI) of PPG is obtained. The simulated results indicate that decreasing the initial concentration ratio of monomer to total chains ( K 1 ) or increasing the rate constant ratio of chain transfer to propagation ( K 2 ) leads to smaller PDI. Reducing the concentration of DMC can induce larger PDI. When the PPG's initial PDI (i.e., PDI of initiator) increases, PDI of the final PPG grows up linearly. However, with the increase of monomer conversion, PDI increases first and then decreases, that is, there is a critical conversion. The possible lack of chain transfer at the beginning of polymerization and the insufficient chain transfer caused by increased K 1 , decreased concentration of catalyst, and decreased K 2 will cause larger PDI, namely, broad MWD.