A kind of preparation method of macromolecular emulsifier capable of free radical copolymerization

Abstract

The invention relates to a preparation method of a macromolecular emulsifier capable of free radical copolymerization. The emulsifier prepared by the method is a hydrophilic macromolecular emulsifier capable of free radical copolymerization. The method is to first put a certain amount of cyclic compounds that can undergo ring opening of active hydrogen, neutral alcohol hydroxyl compounds or polymers, hydroxy acid compounds that do not undergo intramolecular dehydration, and a small amount of polymerization inhibitors into a four-stage nitrogen device. In the flask, stir and reflux to condense, raise the temperature to 145-150°C, then add the weighed acrylate monomer containing hydroxyl group and double bond to the above solution dropwise within 1 hour, after the dropwise addition is completed, Insulate and react for 7‑8h, cool down and add neutralizer, and discharge. The invention has the advantages of low cost, strong operability, safety and high economic value, and has excellent emulsifying effect on acrylic emulsion, styrene-acrylic emulsion and chlorinated vinegar emulsion prepared by emulsion polymerization or emulsion as seed polymerization, and can be prepared by emulsification The resulting emulsion has better particle size and better stability.

Description

technical field [0001] The invention belongs to the technical field of preparation of acrylic emulsion, seed emulsion, styrene-acrylic emulsion, etc., and in particular relates to the technical field of preparation of a free radical copolymerized macromolecular emulsifier emulsion. Background technique [0002] Emulsification is the effect of one liquid uniformly dispersed in another immiscible liquid in the form of tiny droplets. Emulsification is a liquid-liquid interface phenomenon. Two immiscible liquids, such as oil and water, are divided into two layers in a container. The oil with low density is in the upper layer, and the water with high density is in the lower layer. If appropriate surfactant is added and the oil is dispersed in water under strong stirring, an emulsion is formed. This process is called emulsification. The method of emulsification is divided into two methods: external emulsification and self-emulsification. External emulsification is mainly carried ...

AI Technical Summary

Problems solved by technology

Small molecule emulsifiers have good hydrophilicity. In the later stage of paint making process, small molecule emulsifiers remain in the paint film, which will easily cause poor water resistance and other performance defects of the paint film.

In addition, when the small molecular emulsifier emulsifies the large molecular weight acrylic resin, the required dosage and emulsification time are also longer, and the emulsion prepared after emulsification is also unstable and prone to demulsification

Although the macromolecular emulsifier that does not undergo free radical copolymerization will not cause the water resistance of the paint film to deteriorate in the emulsion system, it will always remain in the system and cannot be removed. If the macromolecular emulsifier is damaged by external factors in the system , which will directly lead to emulsion instability and demulsification

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