Deuterium isotope effects on swelling-shrinking states of polymer gels in aqueous solutions:Fluorescence study

Abstract

We have investigated the deuterium isotope effects on the microenvironment of the swelling-shrinking state of typical aqueous polymer gels (poly(N-isopropylacrylamide) gel and polyacrylamide gel) in aqueous binary solutions (methanol/water and acetone/water) by using a fluorescence probe. For comparison, we have also investigated the microenvironment of the linear polymers in the binary mixtures by using a fluorescence probe. Interestingly, the deuterium isotope effects in the bulk changes of poly(N-isopropylacrylamide) gel and polyacrylamide gel in the low organic-solvent composition region show opposite behaviour to each other, but the deuterium isotope effects in the microenvironment changes of (poly(N-isopropylacrylamide) gel and polyacrylamide gel display similar characteristics.