Chemical Modification of Chitosan; 1.Synthesis and Characterization of Chitosan-g-Poly(4-vinyl-pyridine) Graft Copolymers
Kim KS, Lim JK, Cho SH, Kim SJ
Chitosan의 화학적 Modification; 1.Chitosan-g-Poly(4-vinylpyridine)그라프트 공중합체의 합성 및 특성
김공수, 임정규, 조석형, 김수종
Abstract
Graft copolymerization of 4-vinylpyridine onto chitosan was investigated in an aqueous medium by using ceric ammonium nitrate(CAN) as initiator. The optimum conditions for the graft copolymerization were reaction time;2hrs., reaction temperature;30℃, initiator concentration;3.5×10-3mol/l, when the monomer concentration was 0.2mol/l. The aqueous equilibrium swelling properties of a series of crosslinked copolymers using glutaraldehyde as crosslinker were measured as a function of pH at 25℃. The degree of swelling is highly pH dependent, and, especially, the variation of water content was very abrupt between pH4.6 and pH6.0. Tensile strength and elongation value of higher grafted copolymer decreased.
Chitosan에 4-vinylpyridine의 그라프트 공중합은 수용액중에서 개시제로 ceric ammonium nitrate(CAN)를 사용하여 행하였으며 모너머의 농도가 0.2mol/l일 때 그라프트 공중합의 최적조건은 반응시간;2시간, 반응온도;30℃, 개시제농도;3.5×10-3mol/l이었다. Glutaraldehyde로 가교시킨 공중합체의 팽윤도는 pH에 매우 의존적이며 특히 pH4∼pH6에서 급격히 변화하였다. 또한, 인장강도와 신장율은 그라프트율이 증가할수록 증가하였으나 그라프트율이 매우 높은 경우는 신장율이 다소 감소하였다.
References
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