Preparation method of waterborne PES (polyether sulfone) coating

Abstract

The invention belongs to the technical field of polymer materials and particularly provides a preparation method of a waterborne PES (polyether sulfone) coating. The method comprises steps of polymersynthesis, emulsification and purification; a compound precipitation liquid containing a surfactant is designed firstly and is added gradually through a high-speed dispersion device after resin polymerization, so that milk-white mixed slurry is separated out of PES resin gradually in a liquid phase, and the PES coating with different solid content is prepared after separation and purification. Thewaterborne PES coating is prepared directly through polymerization, the technological process of production is shortened, the problem of difficulties in product purification and solvent recovery is solved effectively, meanwhile, macromolecular chains of the PES resin are not damaged, and purity and performance of the product are guaranteed. The waterborne PES coating prepared with the method is small in particle size, stable in performance and capable of being widely applied to the field of heat-resistant and corrosion-resistant coatings.

Description

technical field [0001] The invention belongs to the technical field of polymer materials, in particular to a preparation method of a polyethersulfone water-based coating. Background technique [0002] Polyethersulfone (PES) is an amber transparent non-crystalline resin with excellent comprehensive properties such as heat resistance, flame retardancy, chemical stability, and dimensional stability, and has good stress crack resistance. Its temperature at 180 ° C Creep resistance is the highest among thermoplastic resins. The structural formula of polyethersulfone water-based coating is: [0003] [0004] There are rigid benzene rings and flexible ether groups in the molecular chain, and the sulfone group forms a large conjugated system with the entire structural unit. Due to these characteristics, polyethersulfone has high strength, high temperature resistance, radiation resistance, acid resistance, and Oxidation and other advantages, and has excellent characteristics of ...

AI Technical Summary

Problems solved by technology

At present, the domestic preparation of water-based polyethersulfone dispersion generally adopts the long-term wet grinding of polyethersulfone in a ball mill. The main disadvantages of this method are: first, high energy consumption and long production cycle; second, polyethersulfone The particle size is large, the distribution is wide, and the shape is different; the third is that the molecular structure of polyethersulfone resin is damaged by mechanical force, and it is prone to yellowing when applied in downstream industries

[0006] As one of the non-crystalline special engineering plastics, polyethersulfone has excellent comprehensive properties, but it is very difficult to recover the solvent and purify the product in the actual production process of polyethersulfone, because after the polyethersulfone polymerization reaction is completed Due to the good solubility of the product in the solvent, the entire material system is viscous. Most manufacturers often use the method of gradually releasing the product after the synthesis reaction is completed to cool down and then pulverize the product. After pulverization, the powder is obtained for convenience. The production process of subsequent recovery of solvent and by-product salt has the following disadvantages: first, it is difficult to automate the operation, the site pollution is large, and the product in the polymerization tank is easy to remain and affect the next batch production; The catalyst and by-products used are still partly wrapped in the polymer and difficult to purify, resulting in low product purity and limiting the application range of the resin; third, mechanical crushing will inevitably destroy the integrity of the molecular chain, resulting in a decrease in product performance; fourth, In the process of discharging the product, in order to prevent the increase of the viscosity of the material system caused by the temperature drop in the kettle, which is not conducive to discharging, a higher temperature in the reactor will be maintained, which will make the undischarged materials continue to react, while the polymerization kettle in actual production As a result, the discharge time is often longer, which easily leads to a wider molecular weight distribution of the product; fifth, because polyethersulfone is an amorphous polymer, it has good solubility in solvents, and it takes a lot of time for the product to precipitate and solidify in the cooling liquid. reduced productivity

This traditional process is long, resulting in high energy consumption

Purification is also difficult in the traditional production process of polyethersulfone resin, and a large amount of deionized water needs to be consumed, which will also lead to increased energy consumption in the process of solvent recovery

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