摘要
根据自由基水溶液聚合原理,合成2-丙烯酰胺基-2甲基丙磺酸(AMPS)、苯乙烯磺酸钠(SSS)和衣康酸(IA)的三元共聚物缓凝剂(AMPS/SSS/IA),采用红外光谱和核磁共振表征其结构,表明所合成共聚物为目标产物。经正交实验得到AMPS/SSS/IA的最佳合成条件:溶液酸碱度pH=7、引发剂加量为3%、反应时间为5 h、反应温度为60℃、单体AMPS、IA、SSS的质量比为57:24:19。测试了缓凝剂不同加量的水泥石24 h抗压强度,结果表明AMPS/SSS/IA可以有效抑制水泥石24h抗压强度的衰减。高温高压稠化实验表明缓凝剂AMPS/SSS/IA加量为0.7%时,140℃稠化时间可达200min。通过X射线衍射、扫描电子显微镜表征,讨论了所合成共聚物的缓凝机理,认为缓凝现象的发生,是因为AMPS/SSS/IA与Ca2+生成了复杂的螯合物抑制了Ca(OH)2晶体的形成和生长,以及引起水化硅酸钙(C-S-H)包覆层的增厚。
A retader with terpolymer 2-acrylamido-2-methyl propane sulfonic acid（AMPS）/sodium styrene sulfonate（SSS）/itaconic acid（IA） was synthesized via the aqueous solution copolymerization of free radical.The synthesized product was characterized by Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy,respectively.The optimum reaction conditions of the copolymerization were obtained via the orthogonal experiment.The optimum reaction conditions were pH of 7 in the solution,3% of concentration by weight of the initiator in total monomers,the reaction time of 5 hours,the reaction temperature of 60 ℃,and the rate of the AMPS： IA： SSS of 57：24：19.The experiments of the cement early compressive strength at different dosages of cement retarder showed that the AMPS/SSS/IA could effectively suppress the cement strength degradation during 24 hours.The AMPS/SSS/IA had an excellent retardation property in a high temperature and a high pressure.The retardation time could reach 200 minutes at 140 ℃.The mechanism of the delayed coagulation of the terpolymer was analyzed via X-ray diffraction and scanning electron microscopy.The cement retardation could be since a） the terpolymer led to the restraint of the formation and growth of the Ca（OH）2 crys-tal,b） the terpolymer chelated Ca2＋ to form chelate complex,and the terpolymer increased the thickness of the（C-S-H） coat.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2012年第5期703-710,共8页
Journal of The Chinese Ceramic Society
关键词
高温缓凝剂
2-丙烯酰胺基-2-甲基丙磺酸/苯乙烯磺酸钠/衣康酸
缓凝机理
油井水泥
high temperature retarder
2-acrylamido-2-methyl propane sulfonic acid/sodium styrene sulfonate/itaconic acid
delayed coagulation mechanism
oil-well cement
