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以芒草为原料,用Na OH/H_2O_2溶液体系预处理制备芒草纤维,在冰醋酸环境下,以浓硫酸为催化剂与醋酸酐酯化制备芒草醋酸纤维素。优化了预处理条件:温度、时间、次数和酯化条件:催化剂量、温度、时间、醋酸酐量,最佳条件下制备出的芒草纤维的纤维素、半纤维素和木质素的质量分数分别为75.3%、17.3%、5.1%,制备出芒草醋酸纤维素的取代度DS=2.8,特性黏度[η]=1.24 d L/g,达到美国联邦贸易委员会指南认定的三醋酸纤维素标准。利用扫描电镜(SEM)和热分析(TG、DSC)对制得样品进行表征。结果表明,可以利用Na OH/H_2O_2水溶液体系预处理芒草原料制备芒草纤维,并进一步酯化制备出高取代度的醋酸纤维素。
Using Miscanthus as raw material, Miscanthus fiber was prepared by pretreatment with Na-OH / H 2 O 2 solution system, and Miscanthus cinnamyl-acetate was esterified with acetic anhydride by concentrated sulfuric acid as catalyst in glacial acetic acid. The conditions of pretreatment, such as temperature, time, number of times and esterification conditions, were optimized: the amount of catalyst, temperature, time and the amount of acetic anhydride. The mass fraction of cellulose, hemicellulose and lignin (DS) = 2.8, intrinsic viscosity [η] = 1.24 d L / g, which meets the criteria of FTC approved by American Federal Trade Commission. The prepared samples were characterized by scanning electron microscopy (SEM) and thermal analysis (TG, DSC). The results showed that Mungbean fiber could be pretreated with Na OH / H 2 O 2 aqueous solution and further cellulose acetate ester was prepared by esterification.