干燥温度对粉末状聚羧酸系减水剂性能的影响

Influence of Drying Temperature on Performance of Polycarboxylate Superplasticizer Powders

以甲氧基聚乙二醇、马来酸酐、甲基丙烯磺酸钠等为原料,合成一种聚羧酸系高效减水剂,并与聚乙烯醇和超细SiO2粉体进行搅拌配制成喷雾干燥料液,在离心式喷雾干燥塔中对料液进行干燥,制备一种粉末状聚羧酸系减水剂,探讨干燥温度对粉末状聚羧酸系减水剂性能的影响。结果表明:在雾化盘转速为14 000 r/min,进料速率为80 g/min的条件下,随着干燥温度的升高,粉末状聚羧酸系减水剂的含水率下降,而滤渣率和休止角先下降后升高;干燥温度对粉末状聚羧酸结构没有很大的影响;最佳干燥温度为160～200℃。

The polycarboxylate superplasticizers were synthesized using methoxy polyethylene glycol, maleic anhydride, and sodium allylsulphonate as raw materials, and the centrifugal spray drying process was used to prepare polycarboxylate superplasticizer powders, stirring with polyvingl alcohol and ultrafine SiO2 powders. The influence of drying temperature on the performance of polycarboxylate superplasticizer powders was investigated. The results showed that the speed of centrifugal atomizer was 14 000 r/min, feed liquid rate was 80 g/min, as the temperature increased, the water content of the powders was decreased, the residue rate and angle of repose decreased and then increased. FTIR spectra indicated that the molecular structure of polycarboxylate superplasticizer powders remained the same after the spry drying. The optimum drying temperature was 160-200 ℃.