Method for improving stability of inverse emulsion system

Abstract

The invention discloses a method for improving the stability of an inverse emulsion system. The method comprises the following steps: (1) uniformly mixing oily liquid with an emulsifier to obtain an oil phase; (2) mixing a monomer and two amphiphilic cationic polymers with water to obtain an aqueous phase; and (3) mixing the aqueous phase with an initiator and the oil phase to form pre-emulsion, and performing inverse emulsion polymerization. According to the method disclosed by the invention, the two amphiphilic cationic polymers with hydrophobic and hydrophilic groups are introduced in the inverse emulsion system to increase the interaction of the two phases of the system so as to improve the stability of the W / O emulsion, and meanwhile the two amphiphilic cationic polymers introduced in the system also have the functions of cationic water-soluble polymers, which also have a positive effect on the application of the product.

Description

Technical field [0001] The invention relates to the field of emulsion polymerization, in particular to a method for improving the stability of an inverse emulsion system. Background technique [0002] Since Vanderhoff et al. (Vanderhoff J W. ACS, 1962, 34:32) used organic solvents as the medium in 1962 to first carry out inverse emulsion polymerization of water-soluble monomers, inverse emulsion polymerization has caused great interest. Inverse emulsion polymerization is to dissolve water-soluble monomers in water and disperse them in a non-polar liquid with the help of low HLB emulsifiers to form a "water-in-oil" (W / O) type emulsion. . This reaction can obtain high-molecular-weight products while obtaining a high reaction rate; the reaction system is a dispersed system, which is easy to transfer heat, and is convenient to realize continuous operation. [0003] The key to inverse emulsion polymerization is to obtain a stable inverse emulsion. The stability of the inverse emulsio...

AI Technical Summary

Problems solved by technology

For example, in the Chinese patent literature whose publication number is CN103131398A, organic acid ester surfactants are used as the main emulsifier to reduce the tension of the oil-water two-phase interface, and organic acid amides are used as co-emulsifiers to strengthen the emulsification and wetting ability of the system. Calcium increases the reserve alkalinity, and the fatty alcohol polyoxyethylene ether surfactant is used as a wetting reversal agent, thereby improving the stability of the W / O emulsion, but this method is costly, and there are too many components in the system and it is difficult to control Proportion

In European patent EP904773A, a high-concentration inorganic electrolyte is added to the water phase to form a more stable W / O emulsion, but the introduction of high-concentration inorganic electrolyte makes industrial production difficult

In the Chinese patent document whose publication number is CN1437645A, a polymer that can be functionalized is added to the oil phase before emulsification, and then the polymer is functionalized with a sulfonating agent, thereby providing additional stability for the emulsion. This method Use concentrated sulfuric acid as the sulfonating agent, and then use ammonia water to adjust the pH value, which makes it difficult to achieve the effect of sulfonation and pH adjustment at the same time, and the operation failure rate is high

U.S. Patent US5927404A uses a new type of solid to stabilize the W / O emulsion, but this new type of solid needs to meet the characteristics of being insoluble in oil-water two-phase, having lipophilic groups, having charge distribution, and extremely small size, and the cost of use is high.

[0005] The above methods are all improvements to the stability of W / O emulsions, but most of the current methods are complicated, difficult to operate, and high in cost, so they cannot be well applied.

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