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作 者:陈一[1] 包永忠[1] 黄志明[1] 翁志学[1]
机构地区:[1]浙江大学化学工程国家重点实验室,浙江杭州310027
出 处:《纤维素科学与技术》2007年第2期17-21,共5页Journal of Cellulose Science and Technology
摘 要:采用非均相催化酯化法合成醋酸丙酸纤维素(CAP),研究了反应时间、温度和催化剂用量对CAP乙酰和丙酰取代度、特性粘度的影响,发现反应温度、反应时间和催化剂浓度增加虽可使产物的取代度增大,但粘度降低,得到优化的反应条件为:催化剂用量1%(wt,相对于纤维素),反应温度60℃,反应时间2 h。酯化反应使纤维素的结晶度降低。Cellulose acetate propionate(CAP) was synthesized by the heterogeneous esterification reaction of cellulose. The influence of reaction temperature, time and the usage of H2SO4 catalyst on the degree of substitution of acetyl and propionyl, and the intrinsic viscosity of CAP products were investigated. It was found that the degree of substitution increased as the reaction temperature, time and the usage of catalyst increased. The optimised reaction condition was obtained as follows: the usage of catalyst was l%(wt) to cellulose, reaction temperature 60℃, and reaction time 2h. The esterification resulted the decrease of crystallinity of cellulose.
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