Chemical Science Review and Letters ISSN 2278-6783 DOI:10.37273/chesci.cs205302451 Chem Sci Rev Lett 2022, 11 (42), 252-259 Article cs205302451 252 Research Article Synthesis and Characterization of Apple Pectin Acrylamide-Based Hydrogel by Thermal-Induced Graft Copolymerization Suman Kumar 1 , Raj Kumar Thakur 2 and Lalit Guleria 3 * 1 Department of Chemistry, AP Goyal University Shimla, HP 171009 2 Department of Chemistry, Vallabh Govt. College Mandi-175001 3 Department of Chemistry, Govt. College, Solan, HP-173205 Introduction The present study aims to develop cost-effective eco-friendly novel hydrogels from pectin extracted from apple pomaces, a major waste in fruit processing plants, especially in Himachal Pradesh and Jammu Kashmir and same time utilising the peel waste for the production of dry pectin. Grafting is a clean and convenient method for polymeric modification. The number of hydrogels was synthesized by graft cross-link copolymerization of acrylic acid using N, N-methylene – bis – (Acrylamide) [1]. The bifunctional and trifunctional crosslinking agents like 3 – oxopentamethylene dimethacrylate, trimethlopropane trimethacrylate (TPT) are also used to get gels with desired characteristics from these monomers. The commonly used hydrogel is Poly (2 – Hydroxyethyl methacrylates) [poly (HEMA)]. A wide variety of monomers has been successfully grafted by Misra et. al. onto starch, wool [2, 3] cellulose [4] and gelatin [5] by use of radical initiators. Pectin is a heterogeneous grouping of acidic structural polysaccharides degraded by an oxidizing agent like KMnO4 and by irradiation. Biological applications [6-12], water purification [13] ion-exchange treatment [14-19] and sensing capabilities [20] of Pectin based hydrogel had already been reported in recent years. Material and Methods Pectin was extracted from apple Pomaces by the reflux Digestion method [21]. Acrylamide (S.D. Fines, Mumbai, India) was grafted by a redox system comprising Potassium peroxydisulphate - Sulphuric acid to get optimum polymer yield. Homopolymer separated with acetone (Reagent Grade) and extracted in Methanol. Graft Copolymerization Graft Copolymerization of Acrylamide onto Pectin was carried out under previously determined optimum conditions. The effect of variation of various Reaction parameters on grafting of Apple Pectin and Acrylamide was studied by keeping One Parameter Fixed. One gram of Pectin, Potassium peroxydisulphate (0.55487 x 10 -3 M), Acrylamide (14.068 x 10 -3 M) was immersed in a flask containing water 20 ml of distilled water for one hour at 55 0 C with variable concentration of Sulphuric Acid. The optimum condition for Sulphuric acid (75.040 x 10 -3 M) was fixed and an Abstract Potassium peroxydisulphate has been used as an initiator in an acidic medium for the preparation of Hydrogels through the interpenetrating networks chain. The grafting of hydrogel was initiated by a redox system comprising Potassium peroxydisulphate – Sulfuric acid (KPS – SA). Structural aspects of graft copolymers have been characterized by FT-IR, Viscosity Study, SEM and Swelling behaviour. Grafting has been studied as a function of the concentration of monomer, an initiator system, reaction time, reaction temperature and the amount of water. Pg (Grafting Percent) is used to express the weight increase in a monomer which is supported by the FT-IR study. Morphology of the Apple Pectin and Apple pectin–g–AAm (Pectin graft AAm Hydrogel) was examined by scanning electron microscopy (SEM) which showed a porous structure with smooth surface morphology of the hydrogel. An attempt has been made to investigate the effect of the concentration of monomer and other reaction variables on the grafting of AAm (Acrylamide) onto Pectin extracted from the apple Pomaces. Keywords: Apple Pomaces, Hydrogel, Morphology, Percent swelling, SEM *Correspondence Author: Ashu Chaudhary Email: drlalitguleria@gmail.com