Solvent-free single-component moisture-curable polyurethane adhesive suitable for wood and preparation method thereof

Abstract

The invention relates to a solvent-free single-component moisture-curable polyurethane adhesive suitable for wood and a preparation method thereof. A raw material formula of the polyurethane adhesivecomprises the following components in percentage by mass: 45.6 to 58% of isocyanate, 18.7 to 30% of polyether polyol, 20 to 27% of polyester polyol, 0.1 to 0.3% of a catalyst and 0.1 to 0.3% of an auxiliary agent, wherein the polyether polyol is a mixture of polypropylene oxide ether polyol with a functionality of 3 and a number-average molecular weight of 5000-6000, random copolymerization polyether polyol of ethylene oxide and propylene oxide, and polytetrahydrofuran ether polyol with a functionality of 2 and a number-average molecular weight of 1000-2000. According to the single-component moisture-curable polyurethane adhesive disclosed by the invention, the polyol in the formula adopts blending of specific polyether polyol and polyester polyol; and the prepared polyurethane adhesive isused for bonding wood, the compression-shear strength of the wood is high after bonding, and the wood is durable in use.

Description

technical field [0001] The invention belongs to the technical field of adhesives, and in particular relates to a solvent-free one-component moisture-curing polyurethane adhesive suitable for wood and a preparation method thereof. Background technique [0002] With the drastic reduction of global forest resources and the implementation of my country's natural forest resources protection project, small wood panels require adhesives with better bonding strength, durability and weather resistance than the wood itself. The amount of adhesive used has become a symbol to measure the technical development level of the wood industry. [0003] It is used as an adhesive in the wood industry, mainly in laminated boards, finger joints, end joints, etc. Among synthetic adhesives, synthetic resins used as wood adhesives generally refer to thermosetting resins. Traditional wood adhesives include resorcinol-formaldehyde resin, phenol resorcinol-formaldehyde resin, melamine-urea-formaldehyd...

AI Technical Summary

Problems solved by technology

For example, Chinese patent CN101319129A discloses a one-component solvent-free moisture-curing polyurethane adhesive and a manufacturing method thereof. The polyurethane adhesive includes polyols, diisocyanates, catalysts, coupling agents and chain extenders, and the polyols are 40 to 70 percent by weight. %, diisocyanate 30~55%, chain extender 0~5%, catalyst 0.1~0.5% and coupling agent 0~1%, the polyurethane adhesive is cured by moisture in the air and materials, and it is aimed at aluminum The bonding between wood and aluminum, but because wood is different from aluminum in terms of moisture content and material itself, the adhesive that can bond aluminum to wood is not necessarily suitable for wood, and the raw material implemented from this patent It can be seen from the table that only ordinary polyester polyols and polyether polyols are used, which may not necessarily solve the initial adhesion problem required by wood adhesives.