为探索木粉在1-烯丙基-3-甲基咪唑氯盐([AMIM][Cl])中的溶解和降解问题,研究了预处理方式、溶解温度和时间以及液固比等对扶桑枝条木粉在[AMIM][Cl]中的溶解率和析出率的影响;分析了影响木粉溶解的关键因素;探讨了阻碍木粉完全溶解的机制。结果表明:预处理方式和溶解温度是影响溶解的最重要因素,用5%NaOH预处理木粉,溶解温度为80℃时,木粉在[AMIM][Cl]中的溶解率达60.20%,析出率为46.57%,球磨、高浓度碱以及高温会加剧原料降解;木粉溶解率很高时,析出率较低,更多的是木粉中天然高聚物的降解,而非真正的溶解;较为温和的条件下,木粉难以全部溶解;木粉在[AMIM][Cl]中的溶解度以及溶液黏度并非阻碍木粉完全溶解的因素,可能是因未溶纤维表面形成了胶体阻止了溶解的继续进行。
The effects of pretreatment methods, dissolving temperature, dissolving time, and liquid-solid ratio on the dissolution rate and the precipitation rate of mulberry powder in [ AMIM] [ Cl] were studied. The key factors and the mechanism of impedinge wood completely dissolution were discussed. The test showed that pretreatment methods and dis-solving temperature were the most important factors. When wood powder pretreated with 5% NaOH dissolved at 80 ℃, and the dissolution rate and the precipitation rate was 60.20% and 46?57%, respectively. However, severe pretreatment such as ball milling or high concentrations of alkali or high temperature would exacerbate degradation. In the case of high dissolving rate but low precipitation rate, wood powder was more degradation than dissolution. On mild conditions, wood powder was difficult to be dissolved. Factors that hinder the wood powder dissolved was not solubility or riscosity,might be the formation of colloid.