H. Catalgil-giz et al., Absolute online monitoring of a stepwise polymerization reaction: Polyurethane synthesis, J APPL POLY, 82(8), 2001, pp. 2070-2077
The feasibility of using a recently introduced method for continuous, absol
ute online monitoring for step-growth polymerization was demonstrated, and
polyurethane synthesis was chosen for the demonstration. The previously rep
orted use of this method was for monitoring free-radical initiated chain-gr
owth polymerization. The technique involves continuously withdrawing a smal
l stream of reaction liquid from the polymerization reactor and pumping it
through a series of light scattering and viscosity detectors. This permits
the absolute weight-average molecular weight and reduced viscosity to be si
multaneously monitored as the reaction proceeds. The final weight-average m
olecular weights of the polyurethane samples were compared to the separate
light scattering measurements of the final products. (C) 2001 John Wiley &
Sons, Inc.