The morphology,swelling performance,temperature resistance and plugging performance of a novel double⁃crosslinked structure temperature⁃resistant polymer microsphere were studied by scanning electron microscopy,laser particle size analyzer and microporous membrane filtration experiments.The results show that the original shape of the microspheres is spherical with smooth surface,and the particle size is mainly distributed between 200 nm and 300 nm.The microspheres swell 5 times after swelling for 30 days at 140 ℃ in an aqueous solution with a salinity of 10 000 mg/L.With the swelling time,swelling temperature and microsphere concentration increasing,the plugging characteristics of the microspheres to the microporous membrane is gradually enhanced.The microspheres with the swelling for 30 d at 140 ℃ have the best plugging effect;with the increase of the pore size of the membrane, the microsphere plugging effect is weakened.The microspheres still have good plugging performance after swelling at 140 ℃ for 30 d,indicating that the microspheres have good temperature resistance.

A series of cationic functional polymers with different cations and molecular weights were used to determine the oil water interfacial tension, Zeta potential and O/W emulsion stability of the oil and water of the Gudong crude oil. It was found that when the molecular weight was almost the same, the bigger of the cationic degree, the better ability of breaking the O/W emulsions by the polymers . And in the region of the investigated concentration, at higher concentration of the polymer, better demulsification effects were obtained. The results of interfacial tension and zeta potential measurements indicated that the reason of the demulsification of emulsion by this kind of cationic functional polymer was the electrical neutralization on the interface between oil and water. That is to say, when polymer was added to the emulsion, it could neutralize the charges on the interface and as a result the oil droplets coalescenced.

The oil-water interfacial tension, interfacial shearing viscosity, emulsion stability and viscosity reducing effect were investigated between two kinds of viscosity reducers and Tahe heavy oil. The results showed that the interfacial tension was decreased greatly by the water soluble viscosity reducer, while the interfacial shearing viscosity was mainly affected by the oil soluble viscosity reducer. The water soluble viscosity reducer was beneficial for the formation of the oil-water emulsion. The oil soluble viscosity reducer could improve the emulsion stability and had good viscosity reducing effect. When the oil soluble viscosity reducer was compounded with the water soluble one, the viscosity reducing effect and emulsion stability were greatly improved compared with the single reducer.

       The matching relationship between the size of SMG-mm crosslinked polymer microspheres and the pore size of the nuclear membrane was studied by filtration experiments. The results show that the plugging effect of the microspheres with different pore sizes is very different, and there is a membrane pore size matched with the size of the microspheres. When the concentration and membrane pore size are the same, the pressure has a significant effect on the filtration results. In a certain concentration range, with the increase of concentration of microspheres dispersed system and filtration pressure, plugging effect is better. While when the concentration exceeds the optimum value, the performance of the plugging effect is more terrible; SEM observation results show that the effective plugging can be formed when the diameter of the microspheres and the pore size of the membrane are the best match.

The influence of salinity on the shape, size and plugging property of crosslinked polyacrylamide microspheres were studied by nuclearpore film filtration experiment and sandpacked model, rheology and dynamic light scattering. The results show that the microspheres with different salinity all plug effectively. The experiments of sandpacked model showed that the salinity has little effect on the plugging properties, and not affects the plugging depth in the model at all. The viscosity of microspheres dispersed system increased with the increasing of shear rate, which displayed the minimal dilatants liquid property, and the salt concentration had little influence on the rheology of crosslinked microspheres. When the salinity increased, the microspheres had more stereo sense and smaller size, but these are only small changes.

Using surface tensiometer, interfacial shear viscosity meter and Zeta potentiometer to analyze the effects on the interfacial properties and emulsion stability when the solid particles (Nano SiO2，NaMMT) in the Daqing oilfield ASP flooding were together with the oil displacement agents(Alkali，Surfactant，Polymer). The results show that the absolute value of Zeta potential on the oil droplet surface increases when adding solid particles to the alkali solution. Adding solid particals to the alkylbenzenesulfonate solution, the interfacial tension increases and the interfacial shear viscosity decreases. The absolute value of Zeta potential on the oil droplet surface increases significantly after adding solid particles to HPAM solution. After adding solid particles to alkali solution, low concentration will worsen the stability of O/W emulsion, whereas high concentration(800 mg/L)will be helpful for the stability of O/W emulsion. After adding solid particles, the stability of O/W emulsion formed by thealkylbenzenesulfonate solution and simulated crude oil decreases, but the stability of O/W emulsion formed by HPAM solution and simulated crude oil becomes worse.