Study On The Hydrogen-Bond Interaction, Miscibility And Cell Affinity Of O-Acylated Chitosan/Poly (L-Lactide) Blend Films

The research and development of tissue engineering in meidicine has attracted polymer scientisits and the likes in pursuit of new biomaterials as scaffold. Both chitosan and PLLA are well-known biomaterials. It is a meaningful work to obtain perfect tissue engineering scaffold through integrating chitosan and PLLA. In this paper, five kinds of O-acylated chitosan (OCS) which can be soluble in chloroform were synthezised. The OCS/ PLLA blend films have been prepared by solution blending. This paper mainly studies the effect of chemical structure of O-acylated chitosan, especially the length of O-acyl side chain and molecular weight of chitosans, on the hydrogen bonds between O-acylated chitosan and PLLA and the miscibility of the blends.In this study, three kinds of O-acylated chitosans with varions side chains (O-octanoyl chitosan (O-OCS), O-lauroyl chitosan (L-OCS) and O-palmitoyl chitosan (P-OCS), Mw=3000Da) and three kinds of O-lauroyl chitosans with different molecular weights (O-lauroyl chitosan (L-OCS), O-lauroyl chitosan (L-OCS) and O-lauroyl chitosan (L-OCS)).The experimental results showed that the lower the length of acyl chloride or the smaller the molecular weight of chitosan, the easier the reaction will take place.The hydrogen-bonding interaction and miscibility of blend films were characterized by FTIR,TG/DSC,WAXD and SEM. The results indicate that strong hydrogen-bonding interactions do exist in the OCS/PLLA blend films; the hydrogen- bonding interaction of OCS/PLLA mainly emerges between the amino groups of OCS and the carbonyl groups of PLLA. The hydrogen bond intensity and the miscibility of blend films had relationship to the length of sidechain of O-acylated chitosans or the molecular weight of chitosans, the shorter sidechain or the smaller the molecular weight of chitosans, the stronger hydrogen-bonding interactions and the better miscible the OCS/PLLA blend films.The bioproperty experimental results indicated that OCS/PLLA blend films are biodegradable and nontoxic. They are biocompatible to animal tissue. All OCS/PLLA blend films are good biomaterials.