以亚硫酸氢钠-过硫酸铵为引发体系通过自由基聚合合成了丙烯酸(AA)/丙烯酰胺(AM)/(1-二甲氨基烯丙基)-膦酸(DMAAPA)/二乙基二烯丙基溴化铵(DDAB)四元共聚物.最佳反应条件为:m(AA)∶m(AM)∶m(DMAAPA)∶m(DDAB)=4.0∶6.0∶0.015∶0.020,w(引发剂)=0.3%,pH=7,反应温度为40℃,单体总质量分数为20%.对AA/AM/DMAAPA/DDAB的分子结构进行了IR、1H NMR表征.研究表明:该共聚物具有良好的耐温、耐盐、抗剪切性能;当该共聚物质量分数为1.0%时,对蒙脱土的防膨率达到84.05%,与质量分数1.0%的KC1复配后测得的防膨率达到95.04%.
A quaternary ammonium salt copolymer was synthesized by acrylamide(AM),acrylic acid (AA),(1-dimethylamino)-allyl phosphoric acid(DMAAPA) and diallyl-diethyl-ammonium bromide (DDAB) using NaHSO3-(NH4)2 S2 O8 by radical copolymeriaztion.The optimum condition was determined as follows:m(AA) ∶ m(AM) ∶ m(DMAAPA) ∶ m(DDAB)=4.0 ∶ 6.0 ∶ 0.015 ∶ 0.020,the appropriate pH was 7,initiator was 0.3%,temperature was 40 ℃ and concentration of monomers was 20%.The structure of the copolymer molecular was confirmed by FT-IR,1H NMR.The copolymer showed good temperature-tolerance,salt-resistant and share-resistant.The anti-swelling rate was 84.05% when the concentration of the copolymer solution was 1.0%,which could be up to 95.04% after mixing with 1.0% KCl.