Branched and linear 2-acrylamido-2-methyl-propane sulfonic acid(AMPS) copolymers, namely BP and LP,as filtrate reducers were synthesized by radical copolymerization of AMPS, acrylamide(AM) and N,N-dimethyl acrylamide(DMAM) in aqueous solution with different initiators. The structures of the copolymers and the performances of cement slurry with the copolymers were investigated by means of FTIR,TGA,GPC,rheometer,and filtration instrument. The results showed that BP and LP had similar chemical composition,molecular weight and molecular weight distribution. However,the thermo-stability of BP was slightly higher than that of LP. Meanwhile, both the viscosity of BP aqueous solution and the viscosity retention of the cement slurry at high temperature were higher. It was indicated that the fluid loss of the cement slurry decreased with increase of the dosage of the copolymers. As temperature rose,the viscosity of the cement slurry containing LP decreased significantly,whereas the consistency retention of the cement slurry with BP was kept at 65.2%of the initial value in the later stage of thickening experiment,which indicated better performance at high temperature. Adding BP or LP into the cement slurry can improve its stability.%以2-丙烯酰胺基-2-甲基丙磺酸（AMPS）、丙烯酰胺（AM）和N，N-二甲基丙烯酰胺（DMAM）为单体，采用不同引发体系通过水溶液自由基聚合分别合成了支链型AMPS共聚物（记为BP）和线型AMPS共聚物（记为LP）降失水剂。利用FTIR、TG、GPC、流变仪和失水仪等分析了共聚物的结构，并考察了共聚物配制的水泥浆的性能。表征结果显示，BP和LP的相对分子质量及其分布接近，BP的热稳定性稍高于LP。BP的水溶液和水泥浆的黏度及高温黏度保留率均高于LP。BP与LP的失水量均随聚合物用量的增加而下降。随温度的升高，LP水泥浆呈明显的高温变稀现象；BP水泥浆在稠化实验后期稠度依然有初始值的65.2%，高温稳定性能较好。加入LP和BP之后的水泥浆的稳定性均得到明显提高。
展开▼
