低水化热聚羧酸减水剂的制备及性能研究

Study on preparation and properties of low cement hydration heat polycarboxylate superplasticizer

采用丙烯酸与(2-羟基苯基)磷酸酯化后得到的具有苯环和磷酸基团不饱和单体(P1),再与丙烯酸、异戊烯醇聚氧乙烯醚共聚制得低水化热聚羧酸减水剂P-DR,其最佳合成配比为:m(TPEG)∶m(P1)∶m(AA)∶m(H_2O_2)∶m(Vc)∶m(ME)=100∶12∶12∶1.1∶0.20∶0.40。净浆和混凝土试验结果表明,P-DR具有较高的分散性和保坍性,能有效降低水泥的水化放热速度,减小混凝土的电通量和收缩。

A low cement hydration heat polycarboxylate superplasticizer(P-DR) is obtained by unsaturated monomer(P1) with acrylic acid and isoprenolpolyoxyethylene ether. P1 is obtained by esterification of acrylic acid with (2-hydroxyphenyl) phosphate,having a benzene ring and a phosphate group,the best synthetic formula is m(TPEG)∶m(P1)∶m(AA)∶m(H2O2)∶m(Vc)∶m(ME)=100∶12∶12:1.1∶0.2∶0.40. The experimental results of concrete slurry and concrete show that the P-DR has high dispersion performance and slump retention ability,effectively reducing the speed of cement hydration and releasing heat,and can reduce the electric flux and shrinkage of concrete.