木素磺酸钙的氧化改性研究

研究了木素磺酸钙 (简称木钙 )的氧化改性工艺 ,比较了几种氧化剂与木钙反应后性能的差异。结果表明 ,过氧化氢对木钙的聚合或降解作用均较弱 ,过硫酸铵在适宜的条件下可使木钙发生聚合反应 ,并显著改善木钙的表面物化性能。过硫酸铵氧化木钙时 ,适宜的氧化条件是过硫酸铵的用量为 4%～ 6 % ,反应温度为 80～ 90℃ ,pH =8～ 10。初步探讨了木钙的氧化聚合机理 ,过硫酸铵在碱性条件下使木钙酚型物发生离子化脱氢 ,产生了游离基 ,从而提高了木钙的反应活性 ,促进了木钙分子游离基之间的聚合反应。

Study of the Oxidative Modification of Calcium Lignosulfonate

The oxidative modification process of calcium lignosulfonate(CLS) was studied.The influence of several oxidizers on the properties of CLS was measured.The results showed that the effect of oxidative degradation and polymerization of hydrogen peroxide on CLS was small.Ammonium persulfate could greatly improve the surface activity and dispersion properties of CLS under the optimum conditions that the amount of ammonium persulfate was 4%-6%,reaction temperature was 80-90 ℃ and pH of solution was 8-10.The oxidation-polymerization mechanism of CLS was discussed.Under alkaline condition ammonium persulfate causes ionization and dehydrogenation of the lignin phenols to form free radicals and thus promotes the polymerization of CLS.