A novel method for Preparation of chitosan-g- Poly acrylic acid / Ag Nano composites via RAFT polymerization method

Chitosan is a well-known abundant natural polymer with relatively good biodegradability, biocompatibility and bioactivity. But the low solubility in water, the insolubility incommon organic solvents has limited its utilization and basic research. In order to overcome these problems chitosan wasfirst reacted with phthalic anhydride in DMF/water(1). Then the controlled grafting modification of chitosan has been achieve by 4-cyano,4-(thiobenzoylthio)valericacid(CTBTVA).We used reversible addition-fragmentation chain transfer (RAFT) polymerization because this technique couldpotentially provide new ways to utilize this abundant natural polymer. It would enable a wide variety of molecular designs to afford novel types of tailored hybrid materials composed ofnatural polysaccharides and synthetic polymers and use in biomedical, industrial, agriculture. Then the graftpolymerizations of acrylic acid were performed at 80 oC. Acrylic acid (AA) was selected as the monomer for the graft polymerization, because the corresponding copolymer willhave the pH-sensitivity and stimulating response, which may be used as degradable matrix for drug delivery applicationsand then we use Nano composite technology because this technology is utilized to improve the antibacterial function of biomedical catheter materials (1) .