Preparation method of aqueous polyurethane dispersion and application of aqueous polyurethane dispersion

Abstract

The invention discloses a preparation method of an aqueous polyurethane dispersion and application of the aqueous polyurethane dispersion. The preparation method of the aqueous polyurethane dispersion comprises the following steps of: adding an isocyanate monomer to a hydroxyl styrene butadiene rubber along with stirring under the protection of inert gas; reacting for 0.5 to 2 hours; heating to 70 to 90 DEG C; adding dimethylolpropionic acid and polyether polyol; reacting for 3 to 5 hours; cooling to 40 to 60 DEG C; adding triethylamine to carry out neutralization reaction for 0.1 to 2 hours; adding deionized water; shearing and dispersing at rotational speed of 700 to 900 revolutions per minute; and adding ethylenediamine to carry out chain extension for 1 to 3 hours, thus obtaining aqueous polyurethane dispersion. The aqueous polyurethane dispersion disclosed by the invention has the advantages that a butyl rubber fragment is introduced, thus a molecular chain can be separated in a microphase separation way, and the intramolecular extinction is caused accordingly, and as the result, the product has the automatic matte performance. A coating prepared through the aqueous polyurethane dispersion disclosed by the invention is high in transparency and great in hand feel.

Description

technical field [0001] The invention belongs to the technical field of polymer material polyurethane, and in particular relates to a preparation method of an aqueous polyurethane dispersion and an application of the aqueous polyurethane dispersion. Background technique [0002] The main chain of polyurethane macromolecules contains many carbamate groups, ether groups, ester groups, urea groups, amides and other groups. It is easy to form inter-molecular or intra-molecular hydrogen bonds between macromolecules, so polyurethane is a synthetic resin with excellent comprehensive properties. One, due to its variety of synthetic monomers, mild, specific and controllable reaction conditions, large room for formula adjustment and its microstructure (microscopic phase separation) characteristics of polymer materials, it can be widely used in coatings and adhesives , foam plastics, synthetic fibers and their elastomers have become one of the indispensable synthetic materials for peopl...

AI Technical Summary

Problems solved by technology

[0002] The main chain of polyurethane macromolecules contains many carbamate groups, ether groups, ester groups, urea groups, amides and other groups. It is easy to form inter-molecular or intra-molecular hydrogen bonds between macromolecules, so polyurethane is a synthetic resin with excellent comprehensive properties. One, due to its variety of synthetic monomers, mild, specific and controllable reaction conditions, large room for formula adjustment and its microstructure (microscopic phase separation) characteristics of polymer materials, it can be widely used in coatings and adhesives , foam plastics, synthetic fibers and their elastomers have become one of the indispensable synthetic materials for people's clothing, food, housing, transportation and high-tech fields. Water-based polyurethane is a coating prepared with water as the dispersion medium, which has low toxicity, non-flammability, and no pollution to the environment. , energy saving, safety, etc., and also has the performance of solvent-based polyurethane coatings. When it is applied to special materials such as leather and packaging, it is often required that the coating film has a matte performance. It is generally popular in the market to add matte powder to the coating. Matting, but the addition of matte powder will greatly reduce the physical and chemical properties of the paint film, so foreign countries are actively looking for a resin that can self-matt. At present, matte resins can achieve matting through differences in compatibility or particle size. Usually Introduce some silicon groups or acrylate macromolecular groups into the resin structure, this method can effectively extinction but will cause the coating film to be cloudy and shiny