What do we know about polyurethane adhesives?
Polyurethane adhesives are quite common products in our daily lives. Every day, we use many things that have to do with these types of adhesives, as they are used to stick materials such as wood, plastic, paperboard, metal or glass.
In construction, furniture and packaging industry, polyurethane adhesives are essential products. In the case of some insulating materials, they play a fundamental role in bonding both mineral and vegetal fibers against each other, or in the joining of insulating panels with metal sheets.
Types of polyurethane adhesives
There are 3 types of polyurethane adhesives:
- Those formed by a single component, which are divided into:
- Rigid, they are cured by heat, which produces a thermo-stable structure.
- Elastic, they are cured by humidity, which produces an elastomeric structure.
- Those formed by two components, which can also be rigid or elastic.
Two-component polyurethane adhesives.
Two-component polyurethane adhesives may be rigid or elastic, depending on the structure acquired by the adhesive once it is solidified or cured, which may be thermo-stable or elastomeric respectively.
The basic components of the 2-component polyurethane adhesives are polyols and isocyanate. Depending on their formulation, the chemical reaction of both components may result in a polymer that has either an elastomeric or thermo-stable structure, resulting in elastic or rigid adhesives respectively.
Applications and examples of polyurethane adhesives
Since two-component polyurethane adhesives can be both elastic and rigid, they are the most widely used, with very diverse applications both in product range and in sectors. As an example, we will mention two major sectors:
Elastic adhesives are widely used in the transport sector, especially in the joining of glass windows in cars, buses etc.
In the construction sector, polyurethane adhesives are used to form all kinds of multilayer elements, a perfect connection with materials such as plastic, wood, plaster, cement asbestos or metal, which allows the construction of sandwich panels, claddings, doors or containers, among others.
Polyurethane adhesives for panels SK11 Factsheet
Two component system, polyol and isocyanate free of blowing agents, which polymerise when mixed, achieving a product with excellent adhesion on any kind of wet and clean substrate.
Component A: Polyol SK10 and SK11 A mixture of polyols containing catalysts, stabiliser agents and mineral charges.
Component B: Isocyanate H MDI (Methylene diphenyl diisocyanate ) modified.
This system presents an excellent adhesion on different substrates (expanded polystyrene, wood, cement-asbestos, gypsum, ceilings…) in the industrial manufacturing of panelled ceiling, containers, etc…
Although it is highly recommended for polyurethane foam slab both applied on walls and sandwich panels. This system is also suitable for air filters industry.
Component polyol must be homogenised with a suitable mixer during 10-15 minutes before it is used.
Carefully mix both components (A and B) with the help of a mechanical stirrer, scraping off well and with care the walls and the bottom.
We recommend the use a gluing roller for the industrial applications, and brush and roller for handily application.
For further specifications such as the characteristics of components, specifications or characteristics of the foam systems, download the factsheet.
Components A and B are sensitive to moisture, and should be stored in sealed drums or tanks. Storage temperature must be kept between +15 and +25 ºC.
Avoid lower temperatures that may build up crystallizations in the isocyanate, as well as higher temperatures that may alter the polyol.
Properly stored, the shelf life is 12 months for the Component A (polyol) and 9 months for the Component B (isocyanate).
Appropriately handled, the system does not present significant risks. Avoid contact with eyes and skin. The instruction given in the Safety Data Sheet must be followed during manufacturing and handling of the system.
Normally, the product is supplied in non-returnable steel drums of 220 litres (blue for component A and black for component B).