Network Development in Films Cast from Emulsions of Polydimethylsiloxane
A current trend in the coatings industry is to shift from solvent based systems to emulsions. In elastomeric coatings cross-linking must occur at some stage during the drying of the latex to obtain useful films. It is also particularly desirable for cross-linking to occur at room temperature. This paper describes such a system based on polydimethylsiloxane (PDMS). It consists of an anionically stabilized emulsion of high molecular weight PDMS terminated with silanol (1), colloidal silica and dialkytin-dicarboxyl-ate curing agent (2). Network formation begins at room temperature before the films are dried and rubbery coherent films form before all the water evaporates from the system. This paper describes the cure process and offers an interpretation of the observed phenomena.
KeywordsIntrinsic Viscosity Emulsion Polymer Polymer Particle Colloidal Silica Cast Film
Unable to display preview. Download preview PDF.
- (1).J. C. Saam and D. J. Huebner, in preparation.Google Scholar
- (2).J. C. Saam, R. D. Johnson and C. M. Schmidt, U. S. Patent 4,221, 688 (1980).Google Scholar
- (7).T. C. Chou and A. Rudin, J. Pol. Sci., 11, 2591 (1973).Google Scholar
- (9).P. J. Flory, “Principles of Polymer Chemistry”, Cornell U. Press, Ithaca, New York, 1963, p. 580.Google Scholar