Polyurethane sealant is a kind of middle and high grade adhesive, which has excellent flexibility, impact resistance, chemical resistance, abrasion resistance, and the most important is its low temperature resistance. Because of its series of advantages, polyurethane sealant is widely used in the following fields.

One, woodworking industry

With the improvement of people's awareness of environmental protection, the wood processing industry has gradually used a new type of environmental protection polyurethane adhesive to replace the formaldehyde based urea-formaldehyde resin in order to reduce environmental pollution. The one-component moisture-curing polyurethane adhesive used in the woodworking industry is liquid and used at room temperature. It usually has high bonding strength, flexibility and good water resistance, and can be bonded to many non-wood base materials (such as metal, plastic, rubber, etc.). The dry and wet strength of single-component polyurethane adhesive is better than that of phenolic adhesive. Before bonding, the bonding substrate surface coated with hydroxymethyl resorcol (HMR) coupling agent can improve the bonding strength.

Second, the shoe industry

China has always been a shoemaking country, and in recent years, the preparation technology of waterborne polyurethane has become increasingly mature. For the adhesion of some low-polarity shoe materials, such as SBS, the peeling strength of polyurethane adhesive is not up to the requirement. The adhesive with high crystallinity, high crystallization rate, high cohesion and high peel strength can be developed by adding viscosifying resin.

Third, packaging industry

Flexible packaging with its light and convenient, fresh for a long time, health, easy storage and transportation, easy to open, less garbage and good shelf effect and other unique comprehensive performance, is now more than hard packaging, such as plastic, glass bottles and cans. Polyurethane adhesive because of its excellent performance, can be different properties of film materials bonded together to get cold, oil, drug resistance, transparent, wear resistance and other properties of flexible packaging composite film. At present, in the domestic and foreign markets, polyurethane adhesive has become the main adhesive used in flexible packaging composite film processing.