黄原酸酯—过氧化氢引发针叶材与甲基丙烯酸甲酯接枝聚合反应的研究

GRAFTING OF METHYL METHACRYLATE ONTO SAWDUST OF SOFT WOOD USING XANTHATE-H_2O_2 METHOD

本文研究了黄原酸酯—过氧化氢引发,针叶材与甲基丙烯酸甲酯的接枝聚合,考查了起始pH、过氧化氢浓度、温度、时间、外加Fe^(2+)、单体浓度、碱预处理浓度和黄原酸酯化程度等因素对反应的影响。在适当的反应条件下,可获得较高的单体转化率和接枝效率;接枝率随单体用量的增加而线性增加。实验发现:外加Fe^(2+)有增加均聚反应,减少接枝反应的作用。碱对底物的溶胀和黄原酸化程度对接枝反应有较大的影响。

Grafting of methyl methacrylate onto soft wood using xanthate-H2O2 method was studied. Grafting parameters, including concentration of H2O2 and monomer, initial pH, reaction time and temperature, degree of xanthation, concentration of sodium hydroxide in pretreatment, and amount of Fe++ adsorbed by the substrate, were carefully examined. Our experiment showed that higher monomer conversion and grafting efficiency could be obtained under suitable conditions, and grafting yield increased lineally with the increase of the concentration of monomer. It was noticed that Fe++ adsorbed by the substrate was harmful to grafting, and favourable to homopolymerization. It was found that the preswelling of the substrate, which was related to the concentration of sodium hydroxide, had a significant influence on grafting.