抗高温环保型增黏剂的合成与性能评价

针对目前常用的无固相钻井液用增黏剂抗温性能和环保性能差的问题，开展了抗高温环保型增黏剂研究。以淀粉（ST）与丙烯酰胺（AM）、2-丙烯酰胺基-2-甲基丙磺酸（AMPS）、甲基丙烯酰氧乙基-N，N-二甲基丙磺酸（DMAPS）、N-乙烯基吡咯烷酮（NVP）和丁基苯乙烯（BS）为原料，采用自由基胶束聚合法合成了增黏剂ZNJ-1，研究了反应温度、反应时间、pH值和引发剂用量对淀粉单体转化率和接枝率的影响，表征了分子结构，并对其流变性能、悬浮性能和环保性能进行了评价。室内试验结果表明，最佳反应条件下，淀粉单体转化率为86.8%，接枝率为44.8%；经180℃老化16 h后，质量分数为1.0%的ZNJ-1溶液的表观黏度为26.0 mPa·s，塑性黏度为17.0 mPa·s，动切力为9.0 Pa，初切力为3.0 Pa，终切力为10.5 Pa。研究表明，增黏剂ZNJ-1的抗温、抗盐能力突出，生物降解性能良好，分子间的疏水缔合效应能够提高钻井液的悬浮稳定性能。 

Synthesis and Properties of High Temperature Resistance and Environmental-Friendly Viscosifier

Considering the poor performance of conventional solid-free drilling fluids in high temperature resistance and environmental protection, research has been conducted for development of viscosifier with desirable heat-resistance and environment-friendly properties. By using starch (ST), acrylamide (AM), 2-acylamido-2-methyl-1-propylsulfonic acid (AMPS), 3-N-(2-methacroyloylethyl)-N,N-dimethylammonio]-propane sulfonate (DMAPS), N-vinylpyrrolidone (NVP) and butyl styrene (BS), viscosifier ZNJ-1 has been developed through free radical polymerization. In addition to the characterization of molecular structures, rheological characteristic, suspension capacities and environmental protection performances of the system have been assessed. Lab test results showed that under optimal reaction conditions, ST had a Monomer conversion rate of 86.8% and a grafting rate of 44.8%. After aging of 16 h at 180℃, the ZNJ-1 solution with mass fraction of 1.0% had apparent viscosity of 26.0 mPa·s,plastic viscosity of 17.0 mPa·s, dynamic shearing of 9.0 Pa and static shearing of 3.0 Pa/10.5 Pa. Research results showed that the newly developed ZNJ-1 had outstanding resistance to heat and salt. In addition, the intermolecular hydrophobic associating effects might effectively enhance the suspension stability of the drilling fluid.