【作者】 刘煜；

【导师】 樊泽霞； 任韶然；

【作者基本信息】 中国石油大学 ， 油气田开发工程， 2010， 硕士

【摘要】 淀粉来源广,价格低,可生物降解,是一种理想的绿色原材料,以其为基材合成的各种改性淀粉在石油领域用途广泛。其中,疏水缔合阳离子淀粉除了含阳离子基团外,还含有少量疏水基团,从而能够具备疏水缔合水溶性聚合物的独特性能,有望在石油开采方面具有更广阔的应用前景。本文通过胶束聚合法,以可溶性淀粉为基材,二甲基二烯丙基氯化铵为阳离子单体,丙烯酸十六酯为疏水单体,与丙烯酰胺一起进行接枝共聚,合成了疏水缔合阳离子淀粉(简记为PSADH)。研究了引发剂用量、单体与淀粉比、表面活性剂用量、阳离子单体用量、pH值、反应温度、反应时间对共聚反应的影响,得出了最佳反应条件:引发剂浓度为2.2×10-3mol/L、单体与淀粉质量比为2.5:1、表面活性剂质量分数为3%、阳离子单体质量分数为15%、体系pH值为6、反应温度50℃、反应时间4h。在PSADH溶液性质方面,研究了聚合物浓度、盐度、温度、剪切速率以及表面活性剂对PSADH溶液表观粘度的影响规律。结果表明:在临界缔合浓度以上,PSADH溶液表现出一定的增粘性、耐温抗盐性和抗剪切性。此外,适量的表面活性剂十二烷基硫酸钠(SDS)可使PSADH溶液表观粘度大幅度增大。本文对PSADH的堵水性能进行了评价,并对其在油田絮凝、增粘方面的应用进行了初步探讨;同时,结合PSADH的分子结构特点,对其在上述三方面的作用机理进行了分析和讨论。结果表明:作为油田用堵水剂,PSADH具有一定的耐温性,以及良好的耐盐、耐冲刷和油水选择性,而且,PSADH冻胶体系也具有较好的堵水性;作为絮凝剂和钻井液用增粘剂,PSADH也具有一定的应用可行性。更多还原

【Abstract】 Starch is a kind of ideal green material due to its abundant resource,low cost and biodegradation. Most of modified starch has a wide range of application in oilfields. Besides cationic groups,a small amount of hydrophobic groups are introduced into hydrophobically associated cationic starch.Therefore,it has some unique performances on hydrophobically associating water soluble polymer.And it will have great application prospect in oil field.In this paper,hydrophobically associated cationic starch (PSADH)has been synthesized through graft polymerization of DMDAAC,HA and AM onto soluble starch by micellar polymerization technique. The effect of initiator dosage,monomers and starch ratio,surfactant concentration,cationic monomer dosage,reaction temperature,reaction time and pH value on graft copolymerization reaction have been studied,and the optimal reaction conditions were determined:content of initiator is 2.2×10-3mol/L,ratio of monomers and starch is 2.5:1,content of surfactant is 3%,content of cationic monomer is15%,pH value is 6,reaction temperature is 50℃,reaction time is 4h.In this paper,the relationships between apparent viscosity of PSADH solution and polymer concentration,salinity,temperature,shear rate and surfactant have been researched. The results showed that above the critical associated concentration,PSADH solution exhibited some good characteristics such as effective viscosity increase,tolerance to temperature,salinity and shear rate. Moreover,adequate surfactant SDS can increase the viscosity of PSADH solution.In this study,the water plugging properties of PSADH were evaluated,and its feasible application used as flocculant and viscosifier in oilfields also were discussed. Their mechanisms were analysed based on the molecular structure of PSADH.The results showed that,to be used as a water shutoff agent,PSADH exhibited good temperature and salt tolerance,flush resistance and good oil/water selectivity. Moreover,PSADH gel system also exhibited good properties for water shutoff. And PSADH also can be used as flocculant and viscosifier for drilling fluid.更多还原