Abstract: High slump-retention type polycarboxylates water-reducing admixture (PCE)was prepared by free radical polymerization principle. Study on the effects of the acid/ ether ratio, the amount of hydrogen peroxide in initiator, the amount of chain transfer agent,the reaction temperatureand the ester monomer with different hydrolysis rate on the slump protection performance. Dissipation kinetics (DPD) of Material Stuido software was used to investigate the PCE self-assembly state in aqueous solution. The results show that the optimal preparation process as follows: acid/ether ratio 2.0, ester/ ether ratio 6.0, H2O2 content 1.4%, chain transfer agent 1.1%, hydroxyethyl acrylate and hydroxyl propyl acrylate were used in combination, which hydroxyl propyl acrylate accounted for 60% of the total amount of the monomer,the reaction temperature is 50 ℃. The results of DPD simulation show that the PCE has a highly curling state in water and tends to be globularl. The high slump-retention type PCE is applied to concrete which is prepared by the above technology,the slump-retention time can achieve 4 h at 30 ℃.
潘阳, 汪源, 汪苏平, 胡志豪, 李正平, 张满, 张云. 高保坍型聚羧酸减水剂的制备及其在水溶液中的自组装行为[J]. 材料导报, 2021, 35(z2): 167-171.
PAN Yang, WANG Yuan, WANG Suping, HU Zhihao, LI Zhengping, ZHANG Man, ZHANG Yun. Preparation and Self-assembly Behavior of High Slump-retention Type Polycarboxylates Water-reducing Admixture. Materials Reports, 2021, 35(z2): 167-171.