关键词: 聚羧酸减水剂, 异戊烯醇聚氧乙烯醚, 常温, 聚合

Abstract: The synthesis process of polycarboxylic water reducer was mainly composed of heating. The synthesis process at ambient temperature has been less reported. To solve this problem, the paper researched the influences of reaction temperature, holding time, feeding time of A and B, acid ether ratio, and ammonium persulfate (APS) weight on the performance of polycarboxylic water reducer that was synthesized by using methyl allyl polyethenoxy ether (TPEG) and acrylic acid (AA) as the main polymeric monomers. Orthogonal experiments showed that when the temperature is 30℃, holding time is 1.5 hours, feeding time of A is 2.25 hours, feeding time of B is 3.5 hours, n(AA):n(TPEG)=3.5:1, and APS ratio is 0.5%, the polycarboxylic water reducer achieves optimum performance. When water-binder ratio is 0.29 and a dosage of 0.25% of such obtained water reducer is used, the initial cement paste fluidity reaches 240mm and the slump loss is 5mm after 1 hour. It has better dispersity and dispersion stability than other polycarboxylic water reducers at the same dosage.

Key words: polycarboxylic water reducer, TPEG, ambient temperature, polymerization