Ffects of Poly{Carboxylate–g–(Ethylene Glycol)Methyl Ether} on the Physical Properties of Cement Paste

Abstract

<p>The comb type poly{carboxylate–g–(ethylene glycol)methyl ether} (P(C–g–E)) copolymers were synthesized at different monomer ratios. The relationship between the synthetic conditions, the molecular weights<br />(Mp, Mn, Mw, Mz and Mw/Mn) and the dispersion ability of these copolymers in cement paste has been established. The molecular weights of P(C–g–E)s were analyzed by GPC. The dispersion abilities and the dispersion stabilities of P(C–g–E)s in cement paste were tested by mini slump testing method. The optimum formulation for P(C–g–E) synthesis was found to be P23MM 17 mol.%: SMS 10 mol.%: MA 8 mol.%: SMA 65 mol.%: APS 0.2 mol.%. The key components in P(C–g–E) synthetic formulation for cement super-plasticizer are SMA and P23MM. The SMA/P23MM in P(C–g–E) synthetic formulation is related to the dispersion ability and stability of P(C–g–E) in cement paste. The SMA/P23MM in P(C–g–E) synthetic formulation also influences the molecular weights and the polydispersity of P(C–g–E). The optimal range of SMA/P23MM in the formulation as a cement superplasticizer is 3.50~5.50. The dispersion ability of cement paste added with the optimum P(C–g–E) is increased more 3 times than those of the others.</p>