The swelling and collapse of hydrogen bonded polymer gels

The volume phase transitions in hydrogen bonded polymer gels are investigated. The elastic contribution is obtained by a modification of the Flory-Rehner approach proposed previously, where the affine deformation assumption is abandoned and instead the assumptions of the c* model of de Gennes are adopted. The mixing term is modified to account for hydrogen bonding. The calculations (both binary and ternary) clearly indicate the possibility of abrupt volume phase transition. Also the existence of LCST and UCST within an accessible temperature range is predicted for gels in mixed solvent systems involving hydrogen bonding. (C) 1999 Elsevier Science Ltd. All rights reserved.