Synthetic-leather-used UV solidifying and flame-retarding polyurethane and preparation method thereof

Abstract

The invention discloses synthetic-leather-used UV solidifying and flame-retarding polyurethane and a preparation method thereof. The method is characterized by comprising the steps that low-viscosity liquid dihydric alcohol and diisocyanate serve as raw materials, side-group phosphorus / nitrogen-containing dihidroxy acrylate is introduced into the polyurethane structure in the form of chain extender, and then side-group phosphorus-containing monohydroxy acrylate is used for sealing the end. Both a main chain and a side chain of the obtained UV solidifying polyurethane contain photosensitive perssad, through the UV solidification, the crosslinking degree and relative molecular mass of resin can be improved, the contradiction between the fact that photosensitive perssad in traditional UV solidifying polyurethane is low in content and the fact that the molecular weight of coating polymer is high in requirement is reconciled, and meanwhile the comprehensive performance of the polyurethane such as wear resistance, scratch resistance, waterproofness, heat resistance and solvent resistance is improved; phosphorus / nitrogen flame-retarding ingredients are 'suspended'on the macromolecular side chain of the polyurethane, the flame-retarding effect is good, and fire retardant is not migrated or separated out and is resistant to hydrolysis in the storage and using processes; in addition, no organic solvent is used in the preparation process of the polyurethane, and the synthetic-leather-used UV solidifying and flame-retarding polyurethane has the advantages of being prominent in greenness, environment-friendliness, health, safety and the like and can be used in synthetic leather manufacturing and coating materials such as leather and textiles.

Description

technical field [0001] The invention belongs to the field of fine chemical manufacturing, and in particular relates to a UV-cured flame-retardant polyurethane for synthetic leather and a preparation method thereof. Background technique [0002] my country is a big country in the manufacture and consumption of synthetic leather. In 2014, my country's synthetic leather production accounted for 73% of the world, with an annual output of more than 7 billion square meters. However, the traditional synthetic leather manufacturing uses solvent-based polyurethane (the annual demand reaches 2 million tons / year), and the polyurethane coating is obtained after the solvent is evaporated through hot air drying technology. The use of organic solvents results in the waste of a large amount of solvent resources and serious environmental pollution, and at the same time causes high energy consumption due to solvent evaporation. [0003] Ultraviolet (UV) curing technology has attracted much ...

AI Technical Summary

Problems solved by technology

However, the flame-retardant component of the flame-retardant UV-curable coating is located in the polyurethane main chain structure in the form of phosphate ester. Since the phosphate ester is easily hydrolyzed, the water-based resin is not resistant to storage and loses its application value.

On the other hand, this technology uses photosensitive groups to block polyurethane, and the crosslinking degree of the obtained UV curable coating is not enough, the molecular weight is small, and the comprehensive properties such as hardness and heat resistance of the coating film cannot be taken into account.