氢氧化钠催化多聚甲醛与苯酚加成阶段工艺研究

Study on the Technology of Addition Stage of Polyoxymethylene toward Phenol with Sodium Hydroxide as Catalyst

采用氢氧化钠催化多聚甲醛与苯酚加成反应。研究了多聚甲醛加料方式、水浴温度、碱浓度和碱液加入量对反应剧烈程度和反应体系温度的影响。结果表明:这些因素都显著影响反应的剧烈程度和反应体系温度;与多聚甲醛分批次加入比较,一次性加入能阻止反应剧烈进行;随水浴温度增高,反应剧烈,反应体系温度变化幅度增大;在氢氧化钠量相同情况下,随碱浓度增大,反应剧烈,反应体系温度变化幅度增大;随碱液加入量增多,反应剧烈,反应体系温度变化幅度增大;反应体系温度变化,对最终产物相对分子质量也有显著影响。

Addition reaction of polyoxymethylene toward phenol was catalyzed by sodium hydroxide. The effects of the feeding mode of polyoxymethylene, the water bath temperature, the alkali concentration, the alkali liquor addition on the violence of reaction and the temperature of the reaction system were studied. The results indicated that these factors affected significantly the violence of the reaction and the temperature of the reaction system. Compared with feeding polyoxymethylene in hatches, the violent reaction would be prevented when polyoxymethylene was fed in one- time. The reaction became violent and the temperature of the reaction system varied wildly as the water bath temperature increased. Under the condition of the equal sodium hydroxide addition, the reaction became violent and the temperature of the reaction system varied wildly as the alkali concentration increased or as the alkali liquor addition increased. The variation in the temperature of the reaction system had a great effect on the molecular weight of the final product.