Poly (dimethylsiloxane) Gelation Studies Academic Article uri icon

abstract

  • Recent experimental gelation studies1 involving the endlinking of poly (dimethyl siloxane)(PDMS) chains of various lengths at various reactive-group concentrations (in a linear PDMS diluent) are interpreted using Ahmad-Rolfes-Stepto (ARS) theory of gelation2. These experimental systems have larger network-chain lengths, and cover wider ranges of initial dilutions of reactive-groups compared with polyester-and polyurethane-forming polymerisations analysed previously3. The PDMS data also include the effects of off- stoichiometry, a previously untested feature of ARS theory. The experimentally-measured delays in the gel-point, relative to the predictions of Flory-Stockmayer (FS) theory4, as functions of the initial dilutions of reactive groups, follow the trends predicted by ARS theory. Quantitative interpretation of the PDMS gel-points using ARS theory yields values for the …

publication date

  • May 4, 2000