抗高温有机硅降滤失剂的合成与作用机理研究

采用自由基聚合方法,以丙烯酰胺(AM)、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)、N-乙烯基吡咯烷酮(NVP)和N-(3-三乙氧基甲硅氧烷基)丙基丙烯酰胺(APTS)为原料制备了有机硅耐温降滤失剂AM/AMPS/NVP/APTS。使用FT-IR光谱表征了分子结构,评价了其钻井液性能。结果表明,随着AM/AMPS/NVP/APTS质量分数的升高,180℃老化16h后的淡水钻井液的常温中压滤失量(FLAPI)和高温高压滤失量(FLHTHP)随之减小。当AM/AMPS/NVP/APTS的质量分数为0.6%时,即可将FLAPI维持在9.2 mL,FLHTHP维持在14.2mL。加入1.0%AM/AMPS/NVP/APTS的淡水钻井液老化后的滤失量,随着温度的升高(150～220℃)而增大(FLAPI:7.8～19.8mL;FLHTHP:13.5～56.7mL),抗温可达200℃。通过测定淡水钻井液中有机硅共聚物的颗粒粒度、吸附量和Zeta电位,分析了该有机硅降滤失剂的作用机理。

SYNTHESIS AND MECHANISM OF AN ORGANOSILICON POLYMER USED AS HIGH TEMPERATURE-RESISTANT FLUID LOSS ADDITIVE

An organosilicon temperature-resistant fluid loss additive(AM/AMPS/NVP/APTS) was synthesized with acrylamide(AM),2-acrylamido-2-methyl propane sulfuric acid(AMPS),N-Vinylbutyrolactam(NVP) and acrylamidypropyl tris(triethylsiloxy)silane(APTS) as raw materials by free-radical polymerization.The structure of the polymer was researched by Fourier transform-infrared spectroscopy(FT-IR),and the properties of drilling fluids of the polymer were evaluated in laboratory.The results show that with the addition of AM/AMPS/NVP/APTS,the American Petroleum Institute filtrate volume(FLAPI) and High-temperature and High-pressure filtrate volume(FLHTHP) of fresh water based drilling fluid decreased gradually after being aged at 180 ℃ for 16 h.FLAPI remained stable at 9.2 mL,and FLHTHP remained stable at 14.2 mL while AM/AMPS/NVP/APTS concentration was 0.6%.With 1.0% AM/AMPS/NVP/APTS added,FLAPI increased from 7.8 mL to 19.8 mL,and FLHTHP increased from 13.5 mL to 56.7 mL with the aging temperature increasing from 150 ℃ to 220 ℃.The thermal resistance of AM/AMPS/NVP/APTS was as high as 200 ℃.Through the determination of particle size,adsorbed amount and Zeta potential on the surface of clay in fresh water based fluid,the mechanism of this organosilicon fluid loss additive was analyzed in depth.