Microwave Low Temperature Plasma-initiated Polymerization Smart Hydrogel

In this paper, two kinds of novel hydrogel systems with good general performances which were called poly[2-acrylamid-2-methylpropanesulfonic-acid](PAMPS) hydrogel and poly[N-isopropylacrylamide/2-acrylamido-2-methylpropanesulfonic-acid](poly(NIPA/AMPS)) hydrogel were synthesized through microwave low temperature plasma initiation polymerization.Mechanical performance of prepared hydrogels was studied through the means of compress module and the effects of all factors on cutting module, comparative strength and the maximum load were also discussed. The results show with the increase of concentrations of crosslinking agent and monomer(total monomers), the decrease of proportion of AMPS and the prolongation of postpolymerizing time, the cutting module increases sharply and the comparative strength decreases, and that with the increase of plasma treatment power and time, the cutting module decreases first and then increases. With the increase of concentrations of crosslinking agent and monomer(total monomers) and the weakening of the strength of plasma treatment, the maximum load of hydrogels increases first and then decreases. With the increase of the proportion of AMPS and the decrease of postpolymerizing time, the maximum load decreases.The crosslinking density of hydrogels were characterized by the means of average molecular weight among crosslinking spots and net chain density and the influences of all factors on the crosslinking density were studied. The results show that with increasing the concentrations of crosslinking agent and monomer(total monomers) and postpolymerizing time, and decreasing the proportion of AMPS, the crosslinking density increases. With the increase of plasma treatment power and time, the crosslinking density decreases first and then increases.The desiccation of hydrogels under natural circumstances was studied, which was affected by the preparing conditions. When increasing the concentrations of crosslinking agent and monomer(total monomers), postpolymerizing time and the proportion of AMPS, the desiccating rates of prepared hydrogels increase.P(NIPA/AMPS) hydrogels were observed on microscope, which shows that with the increase of the concentration of crosslinking agent, the crosslinking network becomes more compact and the gridding is smaller. TG spectrum was measured on a synthetical thermal analysis instrument, which shows P(NIPA/AMPS) hydrogels have good heat stability and cansatisfy practical need.