微波辅助氯化胆碱/乳酸低共熔溶剂法制备高聚合度木质纤维

Microwave-assisted Choline Chloride/Lactic Acid Deep Eutectic Solvents Pulping to Produce Wood Fibers with High Degree of Polymerization

关键词:  微波  低共熔溶剂  纤维素聚合度  力学性能

Key Words:microwave  deep eutectic solvents  cellulose DP  mechanical properties

摘要:以云杉木片为原料、氯化胆碱/乳酸为反应液，采用微波辅助低共熔溶剂法制备高纤维素聚合度的木质纤维，考察了氯化胆碱与乳酸的物质的量比、反应温度、反应时间和水掺杂量等制浆工艺参数对纤维素聚合度的影响。结果表明，微波加热有效地缩短了脱木质素反应所需时间，从而减少了纤维素的酸性降解，有效地保留了木质纤维的纤维素聚合度。在氯化胆碱与乳酸的物质的量比1∶11、反应温度140 ℃、反应时间45 min、水掺杂量3% 时，所制木质纤维的纤维素聚合度最高（1 998），零距抗张强度达261.9 N·m/g，其抄造的纸张也呈现出良好的拉伸应力（51.6 MPa）和韧性（2.0 MJ/m³）。

Abstract:Wood fibers with high cellulose polymerization degree （DP） were prepared via microwave-assisted deep eutectic solvents pulping method using spruce wood chips as material and choline chloride/lactic acid as reaction liquid， and the effects of molar ratio of choline chloride to lactic acid， reaction temperature， reaction time， and water content on cellulose DP were investigated. The results showed that microwave heating shortened the time for delignification， which decreased the acid hydrolysis of cellulose in the acidic medium and maintained high cellulose DP of wood fiber. The as-prepared wood fibers had cellulose DP of 1 998 under conditions， which were molar ratio of choline chloride to lactic acid of 1∶11， reaction temperature of 140 ℃， reaction time of 45 min， water content of 3%， as well as zero-distance tensile strength of 261.9 N·m/g， and the paper made by these fibers also exhibited excellent tensile strength of 51.6 MPa and toughness of 2.0 MJ/m³.