ISSN:
0003-3146
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
A new Monte Carlo (MC) algorithm is reported which enables RAfa +RBfb polymerisations to be simulated. It is based on the random reaction of pairs of groups for intermolecular reaction, with intramolecular reaction weighted according to Gaussian statistics and the size of ring structure being formed. The algorithm counts all the ring structures formed and enables polymerisations to be simulated efficiently up to complete reaction. Gel point and modulus results from trifunctional and tetrafunctional polyurethane-forming polymerisations are modelled, with particular emphasis on the effects on modulus of network defects at complete reaction. More in keeping with experiment, higher reductions in modulus at complete reaction are predicted using the the present algorithm than using Biosym MC software. However, it is shown that quantitative agreement with experiment cannot be obtained unless relationships defining the entropies of various ring structures are elucidated and more accurate modelling of the chain statistics governing the intramolecular reaction forming ring structures of various sizes is used.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/apmc.1996.052400104
