Journal of Applied Polymer Science, Vol.117, No.2, 982-995, 2010
Telechelic Siloxanes with Hydrogen-Bonded Polymerizable End-Groups. II. IR Studies of End-Groups Interactions-Model Amides and Ureas
Hydrogen-bonding phenomena in amides and ureas are of great practical and theoretical importance. In this article, we report on infrared temperature studies aimed at the elucidation of the hydrogen-bonding phenomena of (meth)acrylamide groups directly linked to the alkyl groups of telechelic polydimethylsiloxane (PDMS) which serve as models of monoamides, or linked to the alkyl groups of telechelic PDMS through amide spacers-models of diamides (dipeptides). Similarly, we have examined the hydrogen-bonding phenomena in urea-terminated telechelic PDMSs to which free-radically polymerizable groups (methacrylate, alpha-methylstyryl) are attached. Hydrogen bonding in the derivatives of these substituted silicone amides and ureas in the unreacted (liquid) state has been studied, as well as in films formed via ultraviolet-initiated free-radi-cal polymerization of those reactive end-groups. The extreme flexibility of the silicones provides a medium in which polar, hydrogen-bonding end-groups (amides, diamides, and ureas) phase-separate to form their own domains wherein they can freely aggregate in an essentially unperturbed state, when in the liquid form. When the vinyl end-groups are polymerized, interactions between the hydrogen bonding groups attached to them can be studied in a spatially constrained environment. High thermal stability of the silicones allows the study of the hydrogen bonding (H-bonding) phenomena of these models within a broad temperature range. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 117: 982-995, 2010