Study on preparation and performance of polymaleic water reducer based on allyl polyethylene glycol

A series of polymaleic water reducers based on allyl polyethylene glycol were synthesized in water solution by radical copolymerization.The influence of copolymerization conditions on dispersing performance of the water reducers was investigated.GPC was used to determine copolymer molecular weight and allyl polyethylene glycol percent conversion.The suitable reaction conditions for the copolymer prepared were found as follows:n(APEG2400):n(MAn):n(AM)=1.0:4.0:1.5,initiator dosage of 3.5%(mol),reaction concentration of 60%(mass),reaction temperature of 65 ℃ and dropping time of acrylamide of 8 h,and the prepared water reducers possess good performance in concrete.The slump of concrete was initially 22.7 cm and 22.1 cm after 1 h at the dosage of 0.18wt%.At the dosage of 0.3wt%,the water reducing ratio was 33.5% and the compressive strength at 28 d was increased by 28.8%.In this research,the maleic anhydride content in the all monomers is 13.5%(mass),as it is cheaper than(methyl) acrylic acid,providing basis for low cost and cleanness production of water reducers.