Effects of polyethlene oxide chains on the performance of polycarboxylate-type water-reducers

A series of polycarboxylic acid-based copolymers with block and graft groups of polyethlene oxide (PEO) chains was synthesized; effects of the different PEO chains on the fluidity, Zeta potential and adsorption in cement paste and performances of the copolymer in concrete were discussed. It was proved that properties of the copolymer were affected by the length and density of PEO graft and block chains, and that copolymers with some block PEO chains at a certain length and moral percent had good performances in the water-reducing capability and fluid-retaining ability. Experimental results indicated that this kind of copolymers could be used as a high-range water-reducer because of the effects of electrostatic repulsive force and steric hindrance; one of its applications was to produce high-flowing concrete by incorporating with mineral admixtures, such as fly ash, etc.