The invention discloses a preparation method of an ester type
viscosity reduction type polycarboxylate
superplasticizer. The method comprises the following steps: (1) preparing an esterified
monomer; (2) conducting the copolymerization reaction; (3) conducting the
neutralization reaction. According to the technical scheme of the preparation method,
methyl methacrylate and dimethylaminoethanol, remaining after the preparation of the esterified
monomer, are subjected to ester exchange in the same condition of preparing the esterified
monomer so as to obtain dimethylaminoethyl
methacrylate as a
functional monomer. Therefore, the preparation method is cost-saving and simple in operation. In addition, the
functional monomer is directly introduced into the copolymerization reaction to react with other cationic monomers. During the
polymerization process, anions, cations and
tertiary amine groups are attached to polycarboxylic acid molecular chains, so that the surface adsorbability of
cement particles can be improved. The electrostatic repulsion effect between
cement particles is improved. Not only the ester type
viscosity reduction type polycarboxylate
superplasticizer is good in anti-
sludge effect for sand and gravel materials high in
cement content, but also the ester type
viscosity reduction type polycarboxylate
superplasticizer is good in dispersibility and viscosity-reducing effect.