Effects of the synthetic conditions of poly{carboxylate-g-(ethylene glycol) methyl ether} on the dispersibility in cement paste

Abstract

The objective of this study was to find the relationship between the poly{carboxylate-g-(ethylene glycol) methyl ether} [P(C-g-E)] synthetic conditions and the dispersibility in cement paste. The P(C-g-E)s, which have superior dispersion ability and stability in cement concrete, were synthesized by changing the reaction temperature (R.T.), the reaction time (R.H.) and the initiator concentration (I.C.). The molecular weights and the yields of P(C-g-E)s were analyzed by GPC. Also, the dispersion ability and dispersion stability of P(C-g-E)s in cement paste were tested by the mini slump spread testing method. The dispersibilities of P(C-g-E) in cement paste are strongly affected by the reaction temperature and the reaction time, but weakly affected by the APS dosage in the polymer synthesis. In addition, the dispersibilities of P(C-g-E) in cement paste are more affected by the heavier molecules than the lighter ones in the polymer.