November 22, 2024
Majid Hashemi

Majid Hashemi

Academic Rank: Assistant professor
Address:
Degree: Ph.D in -
Phone: -
Faculty: Faculty of Nano and Biotechnology

Research

Title
Synthesis of chitosan / carboxymethyl cellulose polyelectrolyte hydrogel containing silver nanoparticles
Type Thesis
Keywords
هيدرژل پلي الكتروليت ؛ كيتوسان؛ سلولز؛ كربوكسي متيل سلولز؛ نانو نقره
Researchers Zahra Solati (Primary advisor) , Majid Hashemi (Advisor)

Abstract

In this thesis, the synthesis of a polymer network containing silver nanoparticles is presented. Polymers of natural origin, cheap and biocompatible, carboxymethyl cellulose and chitosan were used. The chains of these polymers with appropriate functional groups can create a network for loading and stabilizing silver with ionic and hydrogen bond interactions. To increase the stability of this polymer network, glutaraldehyde was used as a crosslinker. Solutions with different percentages of glutaraldehyde (0.5, 1, 2 v/v) were used and three water-stable polymer composites were synthesized. The amount of glutaraldehyde can affect the ability of composites to absorb water, and the composite modified with glutaraldehyde 0.5% showed better water absorption. This composite was used to prepare silver-containing nanocomposites. Silver ions were loaded into the grid, and then two reducing agents, chemical sodium borohydride or the natural extract of cystosira brown algae, were used to reduce the loaded ions. The resulting composites were characterized by XRD, SEM, FT-IR and EDS techniques. were found. Based on XRD analysis, for the nanocomposite prepared using algae extract, silver nanoparticle crystals with an average size of 17 nm were found, while in the XRD pattern of silver nanoparticles, prepared by sodium borohydride, the characteristic peaks of silver nanoparticles were not observed separately, which could be due to the small size of the silver particles According to EDS analysis, the weight percentage of silver in the composites, synthesized with algae extract and sodium borohydride, is 23% and 11.5%, respectively. The color maps, obtained from the surface of both composites, showed that silver nanoparticles are well dispersed in the polymer network bed.