Polyurethane systems; it takes place in our living spaces as a material by making it easier to use in many areas. In the adhesive family, polyurethane-based products are actively used in many areas from automotive to construction, from footwear to furniture.
Polyurethane adhesives are a compound that can be meticulously incorporated into different materials and have strength and durability properties that, when cured permanently, give a strong resistance to both water and solvents. Polyurethane based glues have the following advantages over general adhesives;
• Despite its solid structure, the advantage of flexibility,
• Good adhesion resistance in different structures,
• Fast curing time,
• Ability to react at low temperature,
• Good chemical and oil resistance.
There are multiple parameters to be able to talk about good adhesion. The materials to be bonded and the glues must have certain properties.
• Clean surfaces,
• Application of physical or chemical treatment on surfaces to be bonded,
• Suitable for physical and chemical properties of the bonded to be used,
• Ability to application parameters (temperature and humidity).
The interaction between the surface and the adhesive is essential in the bonding process and the strength derived from the molecular structure of the adhesive is important. We can chemically explain this as follows.
The effect caused by the surface layer of a substance showing properties similar to a flexible layer is called “surface tension”. If there is a large contact angle, it is an indication that the liquid-solid gravitational forces
are low, and a small contact angle is indicative of the large forces. Based on this data, as the angle grows, it is difficult for the adhesive to wet the surface, so the adhesion may be weak.
We often hear the terms adhesion and cohesion if glue is used in the bonding process. Adhesion is defined as the sum of the forces that hold the two surfaces to be bonded. In a microscopic measurement, it is seen that the two surfaces to be bonded are approached up to a certain distance, and in this distance range, the glue
molecules provide bonding on all surfaces. Cohesion is the gravitational force between the same molecules. The resistance of the bonded materials to external influences and their resistance to deformation depends on the size of the cohesive forces.
Kobe Polyurethane glue group, which shapes its operations according to customer needs by using this information, provides different advantages.
While rubber binder provides advantages in the amount of usage in hot or cold molds and mold opening time of, cast rubber binder in place provides very good adhesion strength as well as application comfort.
Discontinuous or continuous production of panel group adhesives also provides one-component and two-component products for different applications.
They are one-component systems that provide high adhesion strength together with low viscosity, high surface adhesion in the bonding of sponge foams. Due to its low viscosity, can use the spray application.
Filter adhesives offer fast and slow curing alternatives and high resistance to heat and chemicals. These solvent-free products are used for bonding plastic products as well as filter applications such as automotive, construction equipment, vacuum cleaners and compressors.
Also, outside these product groups;
• Sealant,
• Automobile,
• Furniture,
• Building group,
• Provides fast solutions with industrial glues.
When you contact Kobe Polyurethane for more information, you will be presented with suitable systems according to the characteristics of your application.
Gülhan Sarıgöl – Ar-Ge Mühendisi / R&D Engineer – Kobe Poliüretan / Kobe Polyurethane
Kaynaklar / References
• I.R. Clemitson, Castable Polyurethane Elastomer
• M. Lonescu, Chemistry and Technology of Polyols for Polyurethanes
• M. Szycher, Szycher’s Handbook of Polyurethanes
• U. Eichert, Journal of Coated Fabrics, vol. 24, July, 1994,
• Advances in Polyurethane Technology, Eds., J.M. Buist and H.A. Gudgeon, Maclaren and Sons, London, UK,1968.
• www.adhesiveandglue.com
