Aqueous-oily low-viscosity environment-friendly two-component adhesive and preparation method thereof

Abstract

The invention relates to an aqueous-oily low-viscosity environment-friendly two-component adhesive and a preparation method thereof. The objective of the invention is to provide the environment-friendly polyurethane two-component adhesive which is good in bonding strength, wettability, fire resistance and weatherability, stable in performance and easy to coat. The adhesive is characterized in that the adhesive comprises a component A including water glass and a component B including a mixture of a polyurethane prepolymer and polyisocyanate; the component A contains no or little filler; and in the component B, the content of NCO is 8.5 to 25%, and the content of an organic solvent is 8% to 19.9%. Because the component A contains no or little filler and the component B contains an appropriate amount of an organic solvent, hydroxylated nano-silicon in the water glass and a part of reactive groups wrapped and concealed in the prepolymer are fully activated, so a unique dense interpenetrating polymer network is formed, thereby overcoming the problem of burr formation caused by small amounts of filler and solvents and the problems of poor compatibility and difficult coating caused by multiple solvents and producing unexpected technical effects.

Description

technical field [0001] The invention relates to a low-solvent two-component polyurethane adhesive, especially the water-based component contains water glass and fillers, and the polyurethane component contains polyisocyanate and prepolymer, especially polyisocyanate, prepolymer and organic solvent. Composite two-component adhesive for bonding between metal, stone, wood and other materials. Background technique [0002] As an inorganic glue, water glass has many excellent properties such as high temperature resistance, flame retardancy, low cost, and environmental protection; the molecular chain of polyisocyanate and polyurethane prepolymer contains isocyano group (-NCO) and carbamate group (- NH-COO-), so polyurethane adhesives exhibit high activity and polarity, and substrates containing active hydrogen, such as foam, plastic, wood, leather, fabric, paper, ceramics and other porous materials, as well as metal, glass, rubber Materials with smooth surfaces such as plastics a...

AI Technical Summary

Problems solved by technology

From the substantive technical characteristics of the invention, it can be seen that under certain composition and proportioning of water glass components, adding solvent in the polyisocyanate and prepolymer mixture components can significantly improve the bonding performance of the sizing material and increase the bond strength, However, the increase of organic solvent will reduce the environmental performance of the rubber compound, and when there are more fillers in component A, the two-component mixing and stirring will often cause problems that are not easy to fuse or even phase separation, which will cause local aggregation of the mixed rubber compound, forming Uneven particles and incompatible liquids affect the uniformity, stability, and wettability of the rubber, resulting in uneven coating or even difficulty in coating during sizing, which seriously affects the adhesive performance of the adhesive; Component A does not contain filler or contains a small amount of filler. When there is no solvent or only a small amount of solvent in component B, the two-component compound often produces particle migration and fluffing in the rubber compound, which not only affects the surface state of the glue, but also Seriously affect the mechanical strength and bonding performance of the glue, at least affect the short-term bond strength