A novel dual responsive hydrogelwas synthesized by inversemicroemulsion polymerization, using itaconic acid as pH-responsive monomer and N- isopropylacrylamide as thermo-responsivemonomer. pH- and temperature-sensitivity and dynamic viscoelasticity behaviour of the dual responsive hydrogels were investigated. Dual responsive hydrogels showed remarkable pH- and temperature-sensitivity and enhanced viscoelastic behaviour under high stress. Temperature-induced shrinkage range of the dual responsive hydrogels was higher and broader than that of the conventional poly(N-isopropylacrylamide) hydrogel. FTIR revealed the structure of dual responsive hydrogels. The as-synthesized regular and sphere-like hydrogel particles had the average particle size of 49 nm in the range of 30-78 nm.

A novel hectorite/poly(AM/IA)nanocomposite hydrogel was synthesized by inverse microemulsion polymerization. The influence of hectorite amount on water absorbency rate, gel strength and shearresistance was investigated. Dynamic viscoelasticity behaviour of the nanocomposite hydrogels was also studied. The nanocomposite hydrogels showed suitable water absorbency and shear-resistance, high gel strength, solid-like behaviour in the whole oscillation frequency region and enhanced viscoelastic behaviours under high stress. TEM indicated that the as-synthesized hydrogel particles were regular and spherical in shape with an average particle size of 43 nm in the range of 30-65 nm.