Aqueous polyurethane dispersion with high solid content and low activation temperature, preparation method and application thereof

Abstract

The invention relates to an aqueous polyurethane dispersion with high solid content and low activation temperature prepared by a solvent-free preparation method, which is generated on the basis of a preformed polymer generated by reacting isophorone diisocyanate or a mixture of the isophorone diisocyanate and one or two other isocyanates with polyester glycol or a mixture of the polyester glycol and poly (ester-ether) glycol and / or polyether glycol, and hydroxycarboxylic acid, and selectively reacting with aliphatic polyols of which the molecular weight is between 60 and 400 under the condition without the existence of any organic solvents, wherein the preformed polymer is neutralized and dispersed in warm water to react with the water and / or a chain extender, and the solid content of theaqueous polyurethane dispersion reaches up to about 50 percent. The activation temperature of the aqueous polyurethane dispersion is as low as about 50 DEG C, thus the aqueous polyurethane dispersionis suitable to be used as an adhesive which can adhere polar base materials (such as PVC, ABS and the like) and nonpolar base materials (such as PE, PP, PET and the like).

Description

technical field [0001] The invention relates to an environmentally friendly organic polymer material, that is, a water-based polyurethane dispersion with high solid content and low activation temperature, its solution-free preparation method and its use as an adhesive. Background technique [0002] Aqueous polyurethane dispersions used as shoe adhesives, automotive interior decoration adhesives and vacuum plastic adhesives for furniture manufacture require high solid content (35-55% solid content) and low activation temperature (45-55°C). The water-based polyurethane dispersion used as laminating adhesive for food flexible packaging, in addition to requiring high solid content and low activation temperature, also requires the ability to bond non-polar substrates, such as polyethylene (PE), polypropylene (PP) and polyester (PET) and other plastic films. With the strengthening of environmental protection regulations, the strengthening of production safety, and the requirement...

AI Technical Summary

Problems solved by technology

The weak point of this patent is: (1) based on this patent, the water-based polyurethane dispersion adhesive products U-53 and U-54 are opposite to polar substrates, such as polyvinyl chloride (PVC), propylene-butadiene-styrene Terpolymer plastics (ABS), fabrics, leather, wood and metals have good bonding properties, but have poor bonding properties to non-polar substrates, such as PE, PP and PET; (2) A special sulfonic acid diamine is used as a chain extender to introduce ionic groups, so its manufacturing method must first extend the chain to form a high polymer, and then disperse in water, which increases the difficulty of dispersion, so a large amount of A large amount of acetone is used to reduce the viscosity of prepolymers and high polymers, and a large amount of acetone is used to generate safety problems; (3) there must be a device for reclaiming acetone with a large investment, and there is a Time-consuming and energy-consuming, the steps of decompressing distilling out acetone and reclaiming acetone from the thick product of the water-based polyurethane dispersion (containing 30-50% by weight) of the produced water-based polyurethane dispersion liquid, and the recovery rate of acetone is not very high, resulting in waste of resources Waste, (4) still contain weight percent 0.5-0.8% acetone in the water-based polyurethane product U-53 and U-54 obtained at last

The weak point of this patent is: (1) adopt expensive TMXDI or its mixture with other diisocyanate to make the isocyanate component in formula, and in the weight ratio of this mixed diisocyanate, expensive TMXDI will account for at least 20% %, which will affect the practicability of this aqueous polyurethane dispersion; (2) polyoxypropylene glycol, or its mixture with other oligomer polyols is used as a component of oligomer polyols in the formula, And the weight ratio of polyoxypropylene diol in this mixed polyol component will account for at least 30%, better will account for 50%, the best will account for 70%, the aqueous polyurethane dispersion prepared by polyoxyethylene diol Liquid adhesives, which have poor adhesion to polar substrates and poor high temperature resistance; (3) Obviously, this patent uses expensive TMXDI and liquid polyoxypropylene glycol as key components to achieve no The preparation process of the solvent sacrifices the performance / price ratio of the water-based polyurethane dispersion product

The disadvantage of this patent is that this type of water-based polyurethane dispersion adhesive containing blocked isocyanate groups has an activation temperature of 100-200°C, which obviously cannot be used in most applications.

[0007] The above patents show that: (1) so far there is no one with high solid content (35-55% solid content) and low activation temperature (45-55 ° C), which can bond polar substrates (such as PVC, ABS, etc.), and water-based polyurethane dispersion adhesives that can bond non-polar substrates (such as PE, PP, etc.); (2) So far there is no water-based polyurethane adhesive that can produce high solid content and low activation temperature. Solvent manufacturing method

Images