Effect of Epoxy Resin Emulsion on the Mechanical Properties of Oil Well Cement‐Based Composites

Abstract

Oil well cement is a brittle material, which can not ensure the long-term sealing integrity of oil and gas wells when used in cementing operations directly. As a kind of polymer emulsion material, epoxy resin emulsion has a bright future for improving the properties of the cement slurry. Epoxy resin emulsion was added to oil well cement and its workability and mechanical properties were studied, the stress-strain behavior of cement samples was evaluated, and the microstructure was observed by scanning electron microscope (SEM) and X-ray diffraction (XRD). The results show the epoxy resin emulsion used in oil well cement will affect the fluidity, but the rheological property of cement slurry with different content of resin meets the construction requirements. The resin reduces the water loss of cement paste and has no adverse effect on the thickening time. The compressive strength of cement stone decreases with the increase in resin content. When the content of resin is 6%, the flexural strength and impact strength of the cement sample are the largest, and 50.7% and 20.2% higher than that of the specimen without resin, respectively, after curing for 28 days. Further comparison shows that epoxy resin emulsion can improve the mechanical properties of oil well cement better than styrene-butadiene rubber latex. Meanwhile, the resin obviously improves the deformability and decreases the elastic modulus of cement stone. Compared with pure cement, resin cement slurry has no extra hydration products, but the formation of hydrated calcium silicate is inhibited. The microstructure shows that the resin forms a polymer film in the cement matrix and interweaves with cement hydration products, thus improving the flexibility of cement paste.

Preparation of epoxy resin elastic particles and their application in oil well cement

“…It can be seen that compared with the blank cement stone, the structure of the cement stone with HEEP is less porous and more dense, which is because HEEP is filled in the pores of the cement stone or embedded in the hydration products. When the cement stone is subjected to shear or tensile stress, HEEP, as a flexible deformation part within the cement stone, can play the role of an elastic ball, storing and releasing external impact or vibration energy, 46 thereby reducing the elastic modulus of the cement stone and increasing its elasticity.…”

“…From the figure, it can be seen that there is no difference in the types of hydration products between the two, except that the diffraction peak intensity of Ca (OH) 2 in cement hydration products containing HEEP is slightly lower than that blank cement. 46 This is due to the weak hydrophilicity of HEEP, which forms a low water-solid ratio microenvironment within a certain thickness range outside its surface, slowing down the formation and development rate of Ca (OH) 2 crystals. In summary, the addition of HEEP does not alter the chemical reactions during the cement hydration process, nor does it produce new hydration products.…”

Effect of using Austrian pine cones powder as an additive on oil well cement properties

“…The extraction of resin from pine trees is what encouraged the authors to perform this study. The resin and its emulsions are used as an additive to the cement matrix of concrete and well cement to improve the mechanical properties [ 21 , 22 ]. Consequently, our work is crucial in emphasizing the use of these natural fibers in practical fields.…”