Radiation preparation and thermo-response swelling of interpenetrating polymer network hydrogel composed of PNIPAAm and PMMA

Abstract

Interpenetrating polymer network (IPN) hydrogel composed of hydrophilic poly(N-isopropylacrylamide) (PNIPAAm) and hydrophobic poly(methyl methacrylate) (PMMA) were synthesized by sequential IPN method using γ-rays from 60Co source. Compared with pure PNIPAAm hydrogel, PNIPAAm/ PMMA IPN hydrogel not only behaved with obvious temperature sensitivity, but also had higher mechanical strength. The shrinking rate of the prepared IPN hydogel was slower than that of PNIPAAm hydrogel and the relative shrinkage was higher than that of PNIPAAm hydrogel. The IPN hydrogel with less PMMA was not stable while with more PMMA it was quite stable. In addition, the release of Methylene Blue (MB) from the IPN hydrogel was slower than that from PNIPAAm hydrogel as well.