The effect of primary structural parameters of poly(methacrylic acid) xerogels on the kinetics of swelling

Xerogels of poly(methacrylic acid) (MAXG) with different primary structural parameters (PSP) [number average molar mass between the network crosslinks ( M c ), the crosslink degree (ρ c ), and the distance between the macromolecular chains ( d )] are successfully synthesized by crosslinking free‐radical polymerization. The isothermal swelling curves of synthesized MAXG are measured in distilled water in the temperature range of 25–40°C. The swelling conversion curves of all the MAXG may be described with kinetics model of phase boundary controlled reaction, i.e., contracting area (R2). The values of swelling kinetics parameters ( E a and ln A ) linearly increase with the increase in M c . This work presented a novel and quantum model of the mechanism of xerogel's swelling activation process based on resonant coupling of vibration oscillation of water molecules and vibration modes of xerogel. A quantum nature of E a of swelling process is proved and explained the effects of PSP on the values of swelling kinetics parameters. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013