Synthesis and research on the properties of slump-preserving type polycarboxylate superplasticizer with polyether monomer GPEG.

In this paper, slump-preserving polycarboxylate superplasticizer (GPEG-PCE) was synthesized by free radical copoly merization reaction by ethylene glycol monovinyl polyethylene glycol ether (GPEG), acrylic acid, hydroxyethyl acrylate, and the redox system is hydrogen peroxide/E51 and molecular mass regulator mercappropylic acid (MPA). Discuss the effect of raw material ratio and synthesis process on its performance. The test results showed that the best reaction process parameters of GPEG-PCE are: the initial temperature is 20 °C, the ratio of acid to ether is 1.6, the ratio of ester to ether is 3.6, and the amount of initiator (H₂O₂) and molecular weight regulator (MPA) are 0.40% and 0.63% of macromonomer, respectively. The reaction time is 1 h. The synthesized GPEG-PCE has better dispersibility and slump retention than the slump-retaining polycarboxylate superplasticizer synthesized by HPEG/TPEG polyether monomer. GPEG-PCE and ordinary polycarboxylate superplasticizer are compounded and applied to concrete in a certain proportion, which can make the concrete slumps slightly increased within 3 h. [ABSTRACT FROM AUTHOR]