Water-soluble polyurethane for wood lacquer and preparation method thereof

Abstract

The invention discloses water-soluble polyurethane for the wood lacquer and a preparation method thereof. The water-soluble polyurethane comprises the following raw materials in parts by weight: 165-175 parts of polycarbonate diol, 131-132 parts of isophorone diisocyanate, 0.4-0.6 part of catalyst, 16.5-17.5 parts of dihydromethyl propionic acid, 2.7-3 parts of dihydroxyacetone, 18.5-19.5 parts of 1,4-butanediol, 4-5 parts of acetone, 12.5-13 parts of triethylamine, 6-7 parts of ethylenediamine, 628-638 parts of deionized water and 5-6 parts of adipic acid dihydrazide. The preparation method adopts the preparation technology combining the acetone method with pre-polymer dispersion method, thus effectively reducing the dosage of acetone and increasing the molecular weight of the generated polyurethane; and when the prepared water-soluble polyurethane dispersion forms a film, with the volatilization of water and the reduction of the pH value, the self-crosslinking reactions of ketonic carbonyl and hydrazide group can be performed, thus the after crosslinking density of the film can be increased and the hardness and water resistance of the the film can be increased.

Description

technical field [0001] The invention relates to the technical field of coatings, in particular to water-based polyurethane for wood ware and a preparation method thereof. Background technique [0002] With the enhancement of social environmental protection awareness, a series of environmental protection measures such as low-carbon economy, green environmental protection, energy saving and emission reduction have been put forward one after another, and the coating industry is also developing in the direction of low-VOC water-based coatings. Polyurethane resin has attracted widespread attention from all walks of life because of its good physical and mechanical properties, certain water resistance, and excellent low-temperature flexibility. Solvent-based polyurethane coatings are more and more restricted due to their high VOC emissions, which seriously pollute the ecological environment. Water-based polyurethane coatings not only have the performance of solvent-based polyureth...

AI Technical Summary

Problems solved by technology

[0009] The technical problem to be solved by the present invention is to provide a water-based polyurethane for wood ware and its preparation method, to solve the problems of water resistance, poor solvent resistance, and low hardness of water-based polyurethane in the application of wood coatings, and to overcome the problems of two-component polyurethane wood ware Disadvantages of safety and environmental protection in use