Effect of crosslinking treatment on temperature-responsive character of grafted celluloses

N-isopropylacrylamide (NIPAAm)- and methacryloyl-L-alanine methyl ester (MA -ALa-OMe)-grafted cellulose samples were prepared by photografting on disso lving pulp from softwoods, which was oxidized with periodic acid. The graft ed samples exhibited a temperature-responsive character, where they swelled and shrank in water at 0 degrees C and 50 degrees C, respectively. The mag nitude of the character increased with an increase in the percentage of gra fting, and it was nearly equal between the NIPAAm- and MA-ALa-OMe-grafted s amples. The temperature-responsive character of the grafted samples was imp roved by treating them with crosslinkers such as N,N'-methylenebis-acrylami de and di-ethylene glycol dimethacrylate. The extent of the improvement lar gely depended on the concentration of crosslinker, temperature of crosslink ing treatment, and nature of grafted chains.