Synthesis and degradation of model network polymers

• Main Author: Argyropoulos, Dimitris S.
• Format: Others
• Language: en
• Published: McGill University 1985
• Subjects: Polymers > Deterioration.
• Online Access: http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=72032

Theoretical expressions essentially based on the Flory-Stockmayer statistics of gelation were experimentally examined for their applicability beyond the gel point. By studying the crosslinking process of a polyester network formed from 1,3,5-benzenetriacetic acid and 1,10-decamethylene glycol beyond the gel point, the validity of the expressions was quantitatively confirmed, and their limitations were delineated. === On stepwise degradation of a similar network, increasingly large soluble fractions were obtained at each step, and their weight-average molecular weights increased as the degelation point was approached. The molecular weights and distributions of these fractions were in close quantitative agreement with theory, i.e., they represented a near-mirror image of the molecular weights of sol fractions obtained on crosslinking beyond the gel point. Similar results were obtained by degrading a network prepared by the random crosslinking of monodisperse primary chains of polystyrene. === Experimental support was thus obtained for treating random network degradation by reversing the statistics of the Flory-Stockmayer theory of gelation.