高适应性聚羧酸保坍剂的合成及性能研究

Synthesis and research of high compatibility poiycarboxyiates slump-loss resistance agent

以基业长青聚醚大单体(BTL-PEG)、丙烯酸(AA)、甲基丙烯磺酸钠(SMAS)和基业长青保坍型功能助剂(HH)为不饱和单体,过硫酸铵(APS)为引发剂,巯基乙酸(TGA)为链转移剂,共聚合成高适应性的聚羧酸保坍剂。研究表明,在n(AA)∶n(HH)∶n(BTL-PEG)=1.5∶2.7∶1,SM AS用量为大单体用量的1%,APS用量为单体总质量的0.6%,TGA用量为单体总量的0.2%,反应温度为50℃,反应时间为3 h的条件下合成的保坍剂在低掺量下有较好的坍落度保持能力,与水泥有较好的适应性,与减水剂复配后效果明显优于单掺。

The high workability polycarboxylates slump- loss resistance was synthesis with（ BTL- PEG）, acrylic acid（ AA ）, sodium methylallyl sulfonate （SMAS）and slump -loss resistance auxiliaries agent（ BTL -HH）as unsaturated monomers, using ammonium persulfate （APS）as complex initiator, and thioglycolic acid（TGA） as chain transfer agent. The results show that the better performance can be obtained under such optimum reaction conditions,the molar ratio of AA, BTL - HI-I, BTL - PEG is maintained at 1.5：2.7：1, the dosage of initiator is 0.6%, the content of TGA is 0.2%, the reaction temperature of 50~C and the reaction time of 3 h.The results show that polycarboxylate slump - loss resistance had good slump maintenance and good compatibility with cements at low dosage, mean- while, effect of product mixed with superplasticizer is obviously better than that of single using.