In 1920s, latex was first used in Portland cement abroad. At that time, natural rubber latex was added to mortar and concrete to improve the impermeability and corrosion resistance of concrete. At present, the commercial latex system is mainly styrene butadiene latex system. In the 1980s, parcevaux et al. Confirmed that the latex can be used as an effective additive to prevent air from jumping into the oil well cement slurry. Since then, their research has made great progress, and the latex system is still effective when the temperature is as high as 350 ° f (176 ℃). Through the determination of the corresponding relationship between latex content and water loss of oil well cement slurry, the results show that conventional density cement slurry only needs to add a small amount of latex to achieve the effect of low water loss. At the end of last century, SSB / SSPC successfully completed the first multi bottom well cemented with latex cement in the Asia Pacific region by adding latex to the water mud system.

Ohama et al synthesized a series of styrene butadiene latex with different styrene content, and then added them to the cement slurry to test the dry shrinkage of cement stone after 28 days, and found out the effect of styrene content in styrene butadiene latex on the dry shrinkage of cement stone, and found out the effect of styrene content in styrene butadiene latex on the dry shrinkage of cement stone. They found that when the content of latex in latex cement system is higher than 10%, the dry shrinkage of cement paste is less than that of ordinary mortar without latex, and the research shows that with the increase of styrene content in styrene butadiene latex, the increase of dry shrinkage of latex cement paste is very small. However, when the content of latex is less than 5%, the dry shrinkage of latex cement paste is higher than that of ordinary cement paste. When studying the mechanical properties of cement paste, both compressive strength and flexural strength can effectively reflect its mechanical properties, and their ratio can more directly reflect the brittleness of cement paste material: the greater the ratio is, the greater the brittleness of the material is; on the contrary, the brittleness is smaller, that is, the flexibility is increased, and the mechanical properties of cement paste are improved.

When using latex polymer to improve the comprehensive properties of cement slurry, we can't directly add it into the oil well cement slurry system. At the same time, we need to add additives used with latex, such as regulator, retarder, fluid loss additives, dispersant and defoamer, etc., otherwise the latex cement slurry system can't fully meet the requirements of cementing operation.

Latex toughening agents exist in the form of emulsion. It is a metastable system of latex particles uniformly dispersed in solution. The commercial styrene butadiene latex system still has some defects, such as being easily affected by polar ions, strong mechanical stirring and large temperature difference. It is easy to break the stable structure of the system and demulsify. The so-called latex demulsification is that the latex particles in the latex system aggregate into clusters, resulting in macro flocculation. In latex cement slurry, because the components of cement slurry need hydration reaction, so the cement particles have strong water absorption. When latex is added into cement, the cement particles will quickly absorb the water in latex, so as to make the latex solidify rapidly; in the liquid phase of cement slurry system, high valence cations such as calcium ion and aluminum ion, as well as other polymer oil well cement admixtures The polar functional groups of latex are likely to cause latex instability and demulsification; the latex will be subject to a certain degree of shear force in the mixing process with cement and the pumping process of cement slurry, which makes cementing put forward high requirements for the mechanical stability of latex cement slurry; at the same time, the thermal stability of latex cement slurry is affected by the complex downhole high temperature and high pressure environment It also puts forward very high requirements. In order to improve the stability of the existing latex cement slurry, a certain amount of stabilizer is usually added in the cementing operation.