Abstract:

The polycarboxylate based superplasticizer was synthesized by water solution copolymerization of acrylic acid (AA), sodium methyl acryl sulfonate (SMAS) and allyl polyethylene glycol (JFB-23). Ammonium persulfate (APS) was used as the initiator. The mole ratio of monomers, the dosage of initiator, the polymerization temperature and the reaction time on the performance of polycarboxylate based superplasticizer were investigated. The structure and molecular mass of superplasticizer were characterized by FTIR and GPC. The results indicated that the polycarboxylate based superplasticizer with better performance could be obtained when n(AA)∶n(SMAS)∶n(JFB-23)=08∶3∶1, the dosage of initiator was 4 ％ of the monomer weight, the polymerization temperature was 85℃, the adding time was 2h and the soaking time was 2.5h.

Key words: polycarboxylate based superplasticizer; allyl polyethylene glycol (JFB-23); cement paste fluidity