Solving the sensitivity of concrete to admixture dosage and concrete shrinkage has always been a technical challenge eagerly awaited in the construction industry.A new type of ester polycarboxylate superplasticizer monomer (ACPEG) was synthesizeduses by 3?methyl?3?butenoxyacetic acid (MBA) as the priming agent.The relative molecular mass (Mw) of ACPEG was determined to be 2 389 by an multi?angle laser dispersion spectrumeig scattering instrument,indicating the formation of a polyether monomer structure.The results showed that ACPEG has a unique advantage of low polymerization activity,allowing for the one?step synthesis of superplasticizers at 40 ℃ without risk of explosion.The superplasticizer synthesized from ACPEG exhibited a water?reducing rate of 37.4%,segregation rate of 10.8%,bleeding rate of 6.2% at 1 hour,and surface tension of 35.67 mN/m. Although slightly inferior to superplasticizers synthesized from ester?type monomers (MAPEG) in terms of workability,ACPEG outperformed superplasticizers synthesized from methallyl polyethylene glycol ethers (IPEG) and isoprene polyethylene glycol ethers (TPEG) in concrete slump,bleeding distance,segregation rate,workability,and shrinkage reduction effects.
