利用顺酐渣合成聚羧酸减水剂的研究

摘要

顺酐渣是顺酐生产过程产生的副产物,其中主要含有顺酐、顺丁烯二酸和反丁烯二酸等,经研究可用于混凝土外加剂的合成,在烯丙基聚氧乙烯醚(APEG)与顺酐渣(MALS)摩尔比为1.0∶3.0(顺酐渣按有效含量90％、平均相对分子质量110计算)条件下,引发剂过硫酸钾(KPS)的用量为单体总质量的6.0％,链转移剂烯丙基磺酸钠(SAS)的用量为单体总质量的3.5％时,合成的减水剂性能最佳.顺酐渣异构化对合成减水剂的性能基本没有影响,活性炭脱色能在一定程度上提高合成减水剂的性能,但成本较高.顺酐渣合成的减水剂可以1.1倍替代顺酐合成的减水剂,能有效提高合成聚羧酸减水剂的性价比.%Maleic anhydride slag is by-products during maleic anhydride production, which mainly contain maleic anhydride, maleic acid and fumaric acid. Experiments show it can be used in the synthesis of concrete admixtures. The optimal performance of polycarboxylate superplasticizer (PC) was obtained as the molar ratio of monomers n(APEG) :n(MALS) =1.0:3.0 (Effective content of maleic anhydride slag was 90%,and the average molecular weight was calculated by 110). The dosage of sodium methyl allyl sulfonate and potassium persulfate are 3.5% and 6.0% of total monomers by mass. Isomerization of maleic anhydride slag has no influence on PC,Performance of PC can be improved after decolorization but the cost is higher. The PC using maleic anhydride slag can replace that of using maleic anhydride by 1.1 times,which can improve the performance/cost ratio effectively.