Synthesis, Characteriaztion Of Chitosan-Based Derivatives, Their Hydrogels And Hybrids, And A New Family Of Arginine Based Polyester Urea Urethane

Abstract

Two categories of biodegradable polymeric materials which could be photocrosslinked by UV-cure were synthesized. One is water soluble glycidyl methacrylate chitosan (GMA-Chitosan). Unsaturated methacrylate groups were introduced onto the chitosan backbones as side groups to prepare hydrogel precursors for subsequent UV crosslinking to generate a hydrogel having 3D network structure. The effect of reaction conditions on the degree of substitution was studied. A series of hybrid hydrogels with different composition ratios and with positive or negative charge, GMA-chitosan/2(acryloyloxy) ethyl trimethylammonium (AETA) and GMA-chitosan/vinyl sulfonic acid (VSA) were then prepared by UV photocrosslinking of the methacrylate groups. GMAchitosan is also be used to fabricated hybrid hydrogels with different composition ratios with unsaturated Arginine based polyester amide as the second hydrogel precursor for the study of the wound healing model. The enzymatic degradation, mechanical strength and swelling properties changes of the hybrid hydrogel depended upon the composition ratio of the precursors. When the biodegradable hydrogels were used as protein carriers, the release of bovine serum albumin (BSA) could be controlled by the hydrogel charge density and the rate of degradation of hydrogels. Another main category of polymer materials is Arginine based polyester urea urethane (Arg-PEUU) which is newly synthesized by a two-step solution polycondensation of three monomers: L-Arg hydrochloride alkylene diester (Arg-x-Cl), hexamethylene diisocyanate (HDI) and glycerol [alpha]-monoallyl ether (GAE). Arg-PEUUs can be photo-crosslinked into elastic gels. The newly synthesized polymers and gels were characterized by standard polymer characterization methods like NMR, FTIR and elemental analysis. By adjusting the composition ratio of three monomers, a wide range of hydrophilicity, degradation, thermal and mechanical properties could be controlled.