Highly environment-friendly multipurpose two-component adhesive

Abstract

The invention discloses a highly environment-friendly multipurpose two-component adhesive, and relates to a water glass-polyurethane two-component environment-friendly adhesive capable of bonding various hard base materials. The technical problem to be solved comprises that an adhesive with good thixotropy and bonding performance is prepared. The technical problems of foaming, precipitation and the like caused by adding more fillers into a water glass-polyurethane system can be effectively inhibited; the adhesive is characterized in that in a component A, the ratio of modified water glass to polyether polyol to a filler is (2.6-5):1:(1.7-3.3), or (3.5-4.5):1:(2.0-3.3), the modified water glass is prepared by adding a silane coupling agent into water glass, or adding a silane coupling agentand polyol ester or polyol ether into water glass, and the filler is a substance suitable for being matched with the water glass; in a component B, the ratio of polyester polyol to polyether polyol to a plasticizer to polyisocyanate is 1:(1-1.5):(0.5-1.2):(5.5-12), and the ratio of the component A to the component B is (1-1.2):(1-1.2), or the ratio of polyester polyol to polyether polyol to a plasticizer to polyisocyanate is 1:(1-1.5):(0.5-1.2):(6.5-10), and the ratio of the component A to the component B is (1-1.5):(1-1.5). The adhesive can achieve quick-drying early strength without a catalyst at a low temperature, can effectively inhibit foaming so as to achieve good adhesion strength on a plurality of hard substrates such as steel and iron, and has the advantages of long storage life,a certain antirust flame-retardant effect, low cost, green environmental protection, low carbon and energy saving.

Description

technical field [0001] The invention relates to an environment-friendly polyurethane adhesive, in particular to a water glass-polyurethane two-component environment-friendly adhesive with low VOC and capable of bonding various hard substrates. Background technique [0002] Due to the carbamate group (-NHCOO-) or isocyanate group (end-NCO) in the molecular chain structure of the polyurethane adhesive, it can undergo chain extension, branching and cross-linking with components containing active hydrogen, including water glass and the substrate interface. The joint reaction finally forms a consolidated body with certain adhesive strength and mechanical strength. However, traditional solvent-free polyurethane adhesives such as PUR are not only expensive, but also require high-temperature heating and special tools for application; solvent-based polyurethane is toxic and harmful to the environment; water-based polyurethane is expensive, slow to cure (usually heated), and water-res...

AI Technical Summary

Problems solved by technology

The inventor has tried to add a small amount of polyester, polyester polyol, plasticizer, etc. to the water glass component to further improve the toughness of the rubber compound, or because of its hydrophobicity, it will soon float on the liquid surface so that the conjunctiva will affect the use. A small amount of surfactants and dispersants or the use of their emulsions or water-based components, because the water glass is too far from its density, will gradually separate after adding, affecting the normal use and commodity value of the two-component adhesive, a variety of emulsification, dispersion and The effect of anti-sedimentation treatment is not great. Due to the mutual influence of many properties, it is often difficult to achieve the expected effect by conventional tests and conventional technical means, and the addition of a large amount of emulsifier will also significantly affect the bonding strength and water resistance.

Although a large number of hydroxide ions in the water glass in the water glass-polyisocyanate system will absorb the carbon dioxide produced by the reaction and make the system difficult to foam, it will often occur under the conditions of adding a large amount of filler and rapid reaction and the quality of the two components is close. Foaming with a larger magnification greatly reduces the bonding strength