The Flory-Huggins interaction parameter gsc~ was determined for chemically crosslinked poly(vinyl alcohol) (PVA) hydrogels from swelling pressure and elastic modulus measurements. The PVA gels were prepared in aqueous solutions of different molecular weight (22 000 < M, < 346 000). Crosslinks were introduced at different polymer concentrations (3% w/w ~< c o ~< 12% w/w). It is found that in all systems the values of Zgcl for the crosslinked polymer are greater than the values of X.~oJ for the uncrosslinked material at identical concentrations. The ggc, data reported here seem to be a function only of the polymer concentration and are independent of the details of the network structure. The results are discussed in relation to other work on the crosslink dependence and volume fraction dependence of ;(g,~.
Посилання на статтю:
Effect of crosslinks on thethermodynamics of poly(vinyl alcohol) hydrogels / Gregory B. McKenna* and Ferenc Horkay // Polymer. – 1994. – Vol 35. – P. 5737-5742.