Monte Carlo Simulation Studies of the Polymerization of Polyurethane Block Copolymers. III. Modelling of Premature Phase Separation during Reaction and Differing Reactivities of the Chain Extender and Polyol Using the Simple Sinking Pool Model,
Abstract
Because of the complexities involved in polyurethane reaction chemistry and the difficulties encountered in making experimental measurements, relatively little attention has been paid to determining the precise molecular weight, composition, and hard segment length distributions of polyurethane block copolymers. The available evidence suggests that variations in these distributions can markedly influence structure-property relationships in these materials. Computer models have been developed using Monte Carlo methods that allow for simulation of the polymerization process under various conditions and subsequent calculation of the various distributions. The model developed in this contribution is based on a sinking pool of monomers and is thus termed the simple sinking pool model. This model offers several advantages over previous models; in particular it can simulate effects ude to differing reactivity of the chain extender and the polyol, and effects due to phase separation occurring at varying points in the reaction. The model and rationale behind in the inclusion of lthe various parameters are described, and the effects of varying the model parameters on the simulated composition, molecular weight, and hard segment length distributions are determined and discussed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 08, 1986
- Accession Number
- ADA173944
Entities
People
- James G. Homan
- John A. Miller
- Stuart L. Cooper
- Thomas A. Speckhard
Organizations
- University of Wisconsin–Madison