Self-healable hydrogels with crosslinking induced thermo-responsiveness and regulated properties from water soluble polymer

摘要

AbstractGenerally, thermo-responsive hydrogels are prepared from thermo-responsive polymers like PNIPAM and its copolymers thereof. In this research, self-healable hydrogels with thermo-responsiveness and regulated cloud points (CPs) were prepared from water soluble P(N,N-dimethylacrylamide98-stat-diacetone acrylamide44) P(DMA98-stat-DAA44) through crosslinking induced thermo-responsiveness (CIT) mechanism. The P(DMA98-stat-DAA44) was crosslinked by PEO dihydrazide and DTDPH to regulate CP and mechanical property. The results showed that CP of the hydrogels with PEO23dihydrazide crosslinking almost keep intact with increasing crosslinking ratios because the phase transition depends mainly on the structure of the hydrophobic moiety. However, the hydrogels crosslinked by DTDPH change with crosslinking ratios because the size of resultant hydrophobic structure increases and tends to aggregate. The mechanical property and the CP of the hydrogels can be regulated by co-crosslinking. With DTDPH and PEO dihydrazide co-crosslinking, the CP can be regulated from below to above body temperature. Based on reversible acylhydrazone bond, the hydrogels also showed self-healing property.