The Synthesis and Evaluation of a High Temperature Organosilicate Polymer with High Inhibitive Capacity

Hydrolysis and polycondensation (and hence crosslinking) of the organosilicon functional group in synthesis reactions is a technical problem that is often encountered. To solve this problem, a new organolsilicate polymer (ADMOS) was developed through emulsion polymerization with monomers such as acrylic acid (AA), vinylmethyldimethoxysilane (VMDS) and methacryloxy ethyl trimethyl ammonium chloride (DMC). 2,2'-azobis(isobutyronitrile) (ABIN) was used as initiator in the polymerization reaction. The optimum synthesis conditions are: molar ratio of the monomers AA∶DMC = 3∶1, the concentration of VMDS id 5.0% of the total mass of the monomers, the concentration of ABIN = 0.3%, the reaction temperature = 70 ℃, the total concentration of the monomers = 25%. and pH = 5. Using ¹H-NMR, TGA and GPC, the molecular structure of ADMOS was determined. TGA measurement showed that ADMOS has excellent thermal stability. The inhibitive capacity of ADMOS was tested using linear expansion test, hot rolling test and mud ball immersion test. Liner expansion test results showed that the linear rate of expansion of clay cores was reduced from 83.37% measured by immersing the cores in water to 16.57% measured by immersing the clay cores in 3% ADMOS solution. Hot rolling test with water and 3% ADMOS solution showed that the percent recovery of shale cuttings was increased from 11.82% to 92.85%. Mud ball test showed that ADMOS can effectively hinders the invasion of water molecules into the interior of the mud balls, thereby inhibiting the hydration and dispersion of the clays. The inhibition mechanisms of ADMOS were revealed from a microscopic perspective through Zeta potential measurement, XRD, EDS, AFM and combined IR-TGA analyses.