Synergetic effects of additives on structural properties of acrylamide-based hydrogel
Elham Jafarigol, Mahsa Baghban Salehi, Hamid Reza Mortaheb
Abstract
Acrylamide-based (AM-based) hydrogel samples were prepared as different combinations of carboxy methyl cellulose (CMC), acrylic acid (AA), and N,N,N′,N′-tetra-methylethylene-diamine (TEMED) on via free radical polymerization method. A series of tests were conducted to evaluate the morphologic properties, swelling characteristics, thermal, and mechanical strength of the samples. The tests consist of scanning electron microscope, swelling tests, thermal gravimetric analysis (TGA), amplitude sweep test (AST), frequency sweep tests, and sudden applied strain. The maximum equilibrium swelling ratio (ESR) of about 102 (g/g dry weight) for an all in one sample (poly(AM-co-AA)/TEMED/CMC) was observed, which was attributed to a proposed mechanism regarding carbonic free radical with reductant and oxidant initiators. The thermal stability of this sample with the storage modulus of 567 Pa, was maintained up to 292.95 °C. The independency of storage and loss modulus of poly(AM-co-AA)/TEMED/CMC sample at frequencies less than 18 Hz- confirmed its 3D structure Furthermore, the hydrogel represented significant strength and reversibility against 1%, 50%, and 1000% sudden applied strains. The obtained viscoelastic hydrogel poly(AM-co-AA)/TEMED/CMC with high ESR, heat resistance, and structural strength was then verified as a promising candidate for various applications.