What is the reason for the degumming of polyurethane rubber rollers?

1. The choice of adhesive

Polyurethane rubber roller can form a valence bond and van der Waals force between the molecular polar geopolymer material and the surface of the metal material according to the theory of bonding valence bond to form a tight bond between the material and the metal, and the polyurethane liquid is poured around the metal roller core. There is a certain bonding force between the polyurethane elastomer formed from the raw material and the roller core, but the rice milling roller will generate a large shear force between the polyurethane elastomer and the roller core under the dynamic working state, which is equivalent to the bonding strength between the polyurethane and the metal. Highland requirements.

After the actual test, coating the roller core with multiple isocyanate-based primers (adhesives) has a good effect on enhancing the adhesion. This is because the polyisocyanate can react with the polyurethane material and form a rigid adhesive layer with The core of the iron roll is integrated, and the isocyanate group, benzene ring, and urethane group in the adhesive layer interact with the metro atoms and their oxides on the surface of the metal roll to form chemical bonds or secondary bonds (such as hydrogen bonds), etc. Produces high bond strength between metals.

2. Core processing

The treatment of the cast iron roller core is also one of the keys to prevent the rubber roller from de-cored. To ensure a good combination of the polyurethane rubber roller elastomer and the iron core, the iron core usually needs to be cleaned, such as pickling and rust removal, and organic matter to remove oil and so on. Make sure its surface is clean and free of contamination. Mechanical sandblasting is usually one of the most effective ways to improve bond strength.

The surface roughness of the roller core is increased by sandblasting, which can increase the surface area of the bonding interface several times or even dozens of times, and correspondingly improve the bonding force between the polyurethane and the metal iron core. Make more clinching connection between polyurethane and iron core to improve the bonding strength.

After the iron core is treated, it should be kept dry to prevent it from rusting again. Especially in summer, the moisture in the air will form a water film on the surface of the treated iron core, which will cause the iron core to rust. The roll reaction forms carbon dioxide bubbles in the bond interface layer which greatly increases the bond strength.