Slow-release polycarboxylic acid slump retaining agent (APC) was synthesized with isopentenyl polyoxyethylene polyether (TPEG), hydroxyethyl acrylate (HEA), acrylic acid (AA) and BT intermediate as monomers, hydrogen peroxide (H2O2) as initiator, mercaptoethanol (BME) as chain transfer agent and BL as synthesis promoter. The structure of the polymer was characterized by infrared spectroscopy (FTIR) and gel permeation chromatography (GPC). The effects of the amount of functional monomer, the ratio of ester to ether and the amount of chain transfer agent on the dispersion and dispersion retention of APC were studied by single factor experiments. The results showed that when the dosage of BME was 0.5g, the initial reaction temperature was 35℃, and the ester to ether ratio [n (COO-): n (TPEG)]=3.5, the dispersion and retention of APC were the best. Compared with the common polycarboxylic acid slump protection agent (PCE), the concrete of ACP has a good initial dispersion, a certain sustained release function, and a small collapse loss after three to about four hours.
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