本体聚合法制备新型粉体早强型聚羧酸减水剂

Preparation of early-strength powder polycarboxylic acid superplasticizer by bulk polymerization

采用本体聚合法,以实验室自制聚醚类大单体HD-5000、丙烯酸(AA)、N,N-二甲基丙烯酰胺(DMAA)为聚合单体,巯基乙酸(TGA)为链转移剂,通过高温分解偶氮二异丁酸二甲酯(AIBME)提供自由基引发聚合反应,合成一种新型粉体早强聚羧酸减水剂PC-Z。通过正交和单因素试验研究了反应温度、引发剂投料方式、链转移剂用量以及引发剂用量对PC-Z性能的影响。结果表明,酸醚比为4,DMAA用量为聚醚类大单体质量的40%时,PC-Z具有最佳的分散性和早强性,PC-Z能明显提高水泥砂浆的早期强度,并且具有较好的水泥适应性。

A new early-strength powder polycarboxylic acid superplasticizer was synthesized with self-made HD-5000,acrylic acid(AA),N,N-dimethyl acrylamide(DMAA) as monomers and with thioglycolic acid(TGA) as chain transfer agent through high temperature decomposition azo 2 isobutytic acid dimethyl(AIBME) by the method of bulk polymerization. Through orthogonal test analysis and single factor analysis,the effects of the reaction temperature,initiator feeding way,dosage of chain transfer agent and dosage of initiator on the properties of Polycarboxylic-Z(PC-Z) were stuided. The experimental results show that PC-Z has the best dispersive performance and early strength performance when the ratio of acid ether is 4 and the dosage of DMAA is 40%. PC-Z can obviously improve the early strength of cement mortar and has good adaptability of cement.