Synthesis and response of pineapple peel carboxymethyl cellulose-g-poly (acrylic acid-co-acrylamide)/graphene oxide hydrogels.

Developing biomaterials derived from the renewable resources is an effective and sustainable approach to address environmental and resource issues. Herein, hydrogels were synthesized by grafting copolymerization of acrylic acid and acrylamide onto pineapple peel carboxymethyl cellulose with incorporation of graphene oxide (GO). The structure, swelling, and multiple responses to salt, pH and organic solvents were investigated. The incorporation of GO resulted in a higher cross-linking density of the network and thus decreased the swelling ability. Expansion of the hydrogels occurred at high pH, whereas shrinkage occurred at low pH or in salt solutions and organic solvents/water mixtures, exhibiting multiple responses to pH, salt and organic solvents. Moreover, the hydrogels showed a selective adsorption behavior to various dyes and the incorporation of GO enhanced the adsorption performance. The above results may allude several potential applications of the hydrogels, such as adsorption, smart actuators and drug release fields.