愈创木基型多聚体木素模型物合成工艺条件的优化

Optimization of Synthesis Process Conditions of Polymeric Guaiacyl-type Lignin Model Compound

采用正交试验法研究了β-O-4结构愈创木基型多聚体木素模型物合成工艺条件,优化得出适宜的聚合条件为:时间4.5h,反应温度55℃,溴代乙酰基愈创木酚在二甲基甲酰胺中的质量浓度22%,K2CO3与溴代乙酰基愈创木酚质量比0.7;适宜的还原条件为:时间10h,反应温度40℃,未还原聚合物在二甲基亚砜中的质量浓度1.6%,NaBH4与未还原聚合物质量比1.4。聚合过程中反应时间影响最大,其次为反应温度、溴代乙酰基愈创木酚在二甲基甲酰胺中的质量浓度,最后是K2CO3与溴代乙酰基愈创木酚质量比;还原过程中未还原聚合物在二甲基亚砜中的质量浓度影响最大,其次为NaBH4与未还原聚合物质量比、反应时间,最后是温度。另外,采用1H-NMR表征了最优条件下合成所得的木素模型聚合物。

The optimum conditions and influential factors of synthesis process of polymeric guaiacyl - type lignin model compound linked by β-O-4 were studied. The optimum conditions of polymerization were： time 4.5h, temperature 55 ℃ , mass concentration of bromoacetyl guaiacol in N, N-dimethyl formamide （DMF） 22% , mass ratio of potassium carbonate to bromoacetyl guaiacol 0.7 ;the optimum conditions of reduction were： time 10h, temperature 40℃ , mass concentration of unreduced polymer in dimethyl sulfoxide（DMSO） 1.6% , mass ratio of sodium borohydride to unreduced polymer 1.4. The influence of factors on polymerization： time 〉 temperature 〉 mass concentration of bromoacetyl guaiacol in DMF 〉 mass ratio of potassium carbonate to bromoacetyl guaiacol; the influence of factors on reduction ： mass concentration of unreduced polymer in DMSO 〉 mass ratio of sodium borohydride to un reduced polymer 〉 time 〉 temperature. The polymeric lignin model compound synthesized at the optimal conditions were characterized with ^1 H - NMR.