Reactive polyurethane hot melt adhesive with ultrahigh shear strength at low temperature

Abstract

The invention discloses a reactive polyurethane hot melt adhesive with ultrahigh shear strength at low temperature. The hot melt adhesive comprises the following raw materials in parts by weight: 15-20 parts of isocyanate, 40-55 parts of polyol, 10-15 parts of polycondensation agent, 5-8 parts of tackifier, 8-12 parts of viscosity regulator and 2-5 parts of antioxidant, and the polyol is a combination of any one or more selected from the group consisting of pentaerythritol, ethylene glycol (EG)1,2-propylene glycol (1,2-PG), 1,4-butanediol (BDO), 1,67 hexanediol (HD), neopentyl glycol (NPG), diethylene glycol (EG), dipropylene glycol (I) (PG), trimethylolpropane (TMP) and glycerol. According to the reactive polyurethane hot melt adhesive with the ultrahigh shear strength at the low temperature, by adding the tackifier, the binding power of the reactive polyurethane hot melt adhesive at the low temperature is enhanced, the fluidity of the adhesive and the wettability to an adherend are improved, the binding performance is improved, the required binding strength is achieved, and the reactive polyurethane hot melt adhesive has the ultrahigh shear strength at the low temperature.

Description

technical field [0001] The invention belongs to the technical field of reactive polyurethane hot-melt adhesives, in particular to a reactive polyurethane hot-melt adhesive with ultra-high shear strength at low temperature. Background technique [0002] Reactive polyurethane hot-melt adhesive is an adhesive that combines hot-melt and reactive adhesive. Good and other advantages. The commonly used varieties are polyurethane prepolymers with isocyanate end groups, which are mostly used for hot-melt bonding of plastics such as metal, wood, glass and leather. Inspired by the resin structure of reactive adhesives, scientists introduce reactive active groups into the thermoplastic resin molecules, and the hot melt adhesive composed of them will be cross-linked and solidified through the reaction of the active groups after being applied to the adherend. Forms a thermosetting resin, which improves properties such as bond strength, heat resistance, solvent resistance, chemical resis...

AI Technical Summary

Problems solved by technology

[0003] At present, most of the widely used reactive polyurethane hot melt adhesives will greatly reduce their viscosity at low temperature, resulting in that the hot melt adhesive cannot play a role in various low temperature production and living environments, and does not have the shear strength at low temperature; and the existing The colloid of this type of hot melt adhesive cools too fast after the temperature decreases, resulting in a small adjustment space for the position of the colloid of the hot melt adhesive and the bonded object after contact, resulting in a low bonding success rate; the existing hot melt adhesive It is prone to aging and decomposition at high temperature, and it is easy to cause the bonded objects to fall off, etc.