低取代羟乙基纤维素(HEC)具有成纤潜力,但是目前采用的气固相制备方法不佳,采用液相法制备了HEC,运用正交试验考察了碱化温度、碱化时间、碱化浓度、醚化温度对HEC溶解性的影响,同时通过气相色谱、X射线衍射、核磁碳谱和偏光显微镜对优化工艺下产物的结构和性能进行表征。结果表明:当碱化温度为20℃,碱化时间为1h,碱化浓度为20%,醚化温度为70℃时为相对最优的制备工艺条件。纤维素经过微弱的醚化改性,羟乙基基团取代了纤维素上的部分羟基基团,制备出具有碱溶性的低摩尔取代度(MS)的HEC,且随着醚化程度的加深,HEC结晶度下降,溶解性能逐渐改善,但HEC膜的力学性能有所下降。
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基金资助
国家自然科学基金(51703085);江苏省自然科学基金项目(BK20170189);中国博士后科学基金项目(2019M651574);江苏省博士后科研资助计划项目(2018K108C)