| 초록 |
For the purpose to improve the dimensional stability of chitosan in physiological solution, crosslinked chitosan was prepared by using glutaraldehyde as crosslinker in this study. Crosslinked chitosan was characterized by X-ray diffraction (XRD), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectrometer, and swelling analysis. Changing the crosslinking degree allowed the variation of the crystalline structure and thermal behavior of the material. Crosslinked chitosan was thermally stable up to over 300˚C. The glass transition temperature and cold crystallization temperature varied with the ratio between glutaraldehyde and chitosan. X-ray diffraction patterns showed that the chitosan with different crosslinking degree had different ordered structure. Peak shift toward higher diffraction angle indicated that the chitosan molecules were arranged in a more compact way with the crosslinkage. Moreover, Swelling analysis of lyophilized chitosan showed that the equilibrium water content (EMC) has been decreased from over 90% of the uncrosslinked chitosan to about 10% of the crosslinked chitosan with a crosslinking degree of 50%, and the sample diameter change decreased from 140% to less than 10%. |
