Accession Number:

ADA222996

Title:

Gel Permeation Chromatographic Analysis of Polyurethane Prepolymer Synthesis Kinetics. 1. The Effect of Catalyst

Descriptive Note:

Corporate Author:

TEXAS RESEARCH INST INC AUSTIN

Report Date:

1990-01-01

Pagination or Media Count:

14.0

Abstract:

Polyurethane prepolymers are a complex mixture of oligomers. The proportion of the various species in this mixture determines the handling properties of the prepolymer as well as the physical properties of the final polyurethane. An analytical method has been developed that gives a clear and sensitive picture of both the reaction kinetics and the concentrations of the oligomeric species in the prepolymer mixture. The analytical method is applied to the polypropylene glycoltolylene diisocyanatecatalyst system. The expected changes in reaction rates and in the formation of higher oligomers in the prepolymer were observed when catalyst was added at three different polyol molecular weights. An alternative equation for predicting the number average degree of polymerization is developed for the cases where reactant ratios are significantly less than one. An empirical equation is derived that permits expressing the reaction kinetic data in a linear plot. This equation is used to express the results of this work. Keywords Gel permeation chromatographic analysis, Kinetics, Reprints, Polyurethane, Oligomer ratio, Prepolymer, Catalysts.

Subject Categories:

  • Physical Chemistry
  • Polymer Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE