微波液化木材及聚醚多元醇的制备

以醇解的聚酯(PET)饮料瓶为液化剂,甘油作辅助液化剂,微波辅助加热,用2.5%H2SO4催化液化木材。分别讨论了微波功率、液固比/反应时间和温度对液化率的影响。结果表明,在微波功率500 W,反应时间15 m in,温度150℃,液固比为4的条件下,木材液化率99.16%。以此液化物为起始剂,选用双金属氰化物MMC催化环氧丙烷开环聚合,通过改变环氧丙烷的用量制备了不同聚醚多元醇,并采用傅里叶变换红外(FT-IR)、凝胶色谱(GPC)及热示差扫描(DSC)等分析手段对起始剂和不同聚醚多元醇的结构、分子质量分布和耐热性进行了对比表征。研究表明聚醚多元醇的羟值、酸值、黏度随环氧丙烷用量增加减小,分子质量分布随之变窄,热稳定性下降。

Wood liquefaction by microwave heating and preparation of biomass polyether polyol

The alcoholysis PET beverage bottle,glycerol, 2.5% H2SO4 and microwave radiation were used as the liquefacient,ancillary reagent, catalyst and heating source respectively to achieve liquefaction of wood. The key factors on the efficiency of liquefaction including microwave radiation power,liquid-solid rate,reaction time and temperature were discussed. The degree of liquefaction was up to 99.16% under the reaction conditions of microwave power 500 W,reaction temperature 150 ℃ for 15 min and liquid-solid rate 4.Base on the liquefaction starting agent and double metal cyanide MMC as catalyst of ring-opening polymerization of propylene oxide, the different biomass polyether polyol were prepared using different amounts of propylene oxide. The structure, molecular weight distribution and thermal stability of starting agent and different biomass polyether polyol were contrasted by FTIR, GPC and DSC.The hydroxyl value,acid value and viscosity(20 ℃) of biomass polyether polyol were decreased with the increasing of propylene oxide amount .The molecular weight distribution also became narrow and thermal stability was decreased.