Synthesis and characterisation of hydrogel based on propiolic acid

Abstract

ABSTRACT In this study, using a propiolic acid monomer and ammonium persulphate as initiator and N,N’-methylenebisacrylamide as crosslink agent, poly propiolic acid hydrogel was designed and tested for water absorption. Also, to investigate the effect of pH on hydrogel’s efficiency, swelling was investigated at different pH levels. To obtain the optimal formula for hydrogel with maximum water absorption, the initiator and crosslink agent levels were changed. The obtained data showed that the highest conversion rate of monomer to polymer was observed for the S1 sample with an initiator concentration of 10% by weight and a crosslinking agent with a concentration of 2% by weight. It also has the highest water absorption for this sample and its swelling rate is 27.6 times that of dry hydrogel. Increasing the concentration of the crosslinking agent and reducing the amount of initiator resulted in the reduction of hydrogel swelling in water. Also, the swelling rate of samples at different pH shows that reducing pH to acidic environments or increasing it to basic environments led to a decrease in network swelling in all three samples. Finally, to investigate the structure and morphology of hydrogels, FTIR, SEM, and measuring the amount of hydrogel swelling at ambient temperature tests were used.