两性离子聚合物降滤失剂的合成及评价

Synthesis and evaluation of zwitterionic polymer fluid loss agent

以丙烯酰胺(AM)、丙烯酸(AA)、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)、对苯乙烯磺酸钠(SSS)和二甲基二烯丙基氯化铵(DMDAAC)为合成单体,以自由基聚合法合成了水基钻井液用降滤失剂(PAASDA)。利用FTIR,~1H NMR,DTA-TG,SEM等方法对PAASDA的结构和热稳定进行了表征。采用单因素法确定了适宜的合成条件为:m(AM)∶m(AMPS)∶m(SSS)∶m(AA)∶m(DMDAAC)=30∶40∶8∶15∶7,引发剂用量0.6%(w)。高温老化实验结果表明,在盐水基浆中PAASDA加量为2.0%(w)时,可抗180℃高温;在不同老化温度下滤失性能均比其他磺化降滤失剂优异;在复合盐水聚磺钻井液体系中,老化后滤失量为2.2 mL,高温高压滤失量为8.2 mL,相比常用抗盐降滤失剂,滤失量可降低72.7%,降滤失效果更佳。

A polymer fluid loss agent(PAASDA)for water-based drilling fluid was synthesis by free radical polymerization in aqueous solution used acrylamide(AM),acrylic acid(AA),2-acrylamide-2-methyl propane sulfonic acid(AMPS),sodium styrene sulfonate(SSS)and dimethyl diallyl ammonium chloride(DMDAAC)as monomers.The product was characterized for structure and thermal stability by FTIR,1H NMR,DTA-TG and SEM.The single factor experiment method was used to optimize the reaction conditions were as follows:m(AM)∶m(AMPS)∶m(SSS)∶m(AA)∶m(DMDAAC)30∶40∶8∶15∶7,initiators dosage 0.6%(w)(based on the total monomer mass).In the brine drilling fluid as the copolymer dosage was 2.0%(w),it could resist high temperature of 180℃.Comparing other sulfonated fluid loss agent in different aging temperatures,the filtration performance was excellent;in the compound brine polysulfuric drilling fluid system,filtration loss was 2.2 mL in the aging test,high temperature high press filtration loss was 8.2 mL,compared with the conventional anti-salt filtration loss agent,it could be reduced by 72.7%,and the filtration performance was better.