Cross Linking

[tbramel]

What is cross linking and how does it pertain to injection molding?

[meltflipper]

hi, with in all the plastic configurations in injection molding we have 2 basic plastics type thermoset and thermoplastic, thermoset plastics become a solid by CROSS-LINKING molecules attaching to each others this type of plastic can be molded only ones they can not be re-melted

[Suhas]

In materials like polyolefins one can get the required properties for the product, for example chemical resistance. But then they are not strong enough. Therefore you can cross link the material after it is molded to get the required strength. What cross linking does is that it 'joins' all the molecules to form a network and increase mechanical properties.
As MeltFlipper says above, all thermoset molding processes do the same but the base in this process is not a thermoplastic that you melt and inject.

Hope this helps.
Suhas

[Monomer]

hi, with in all the plastic configurations in injection molding we have 2 basic plastics type thermoset and thermoplastic, thermoset plastics become a solid by CROSS-LINKING molecules attaching to each others this type of plastic can be molded only ones they can not be re-melted

Cross linking in plastic means that the plastic molecules are chemically bonded to one another. The chemical reaction that bonds the thermosets together("cross-links") can be anything from a catalyst to heat. Once that chemical bond is created between the plastics molecular chains the part can no longer be recycled/re-melted due to the chemical bonds breaking apart. Thermoplastic resins are kind of like spaghetti where it is a bunch of polymer chains tangled together that form a plastic. There is no chemical bond between the chains and that's why thermoplastics can be recycled/reheated.

[tbramel]

Suhas,

I understand the cross linking that occurs in Thermoset materials. The reason for my question is, our company was approach by a customer that asked if we were capable to do cross linking on a given product they were thing of placing with us. I don't what material, but it was a thermoplastic resin. I did a little research and there seem to methods of creating a cross linking in thermoplastics that improves the given properties of the resin. For example: Electron Beam cross linking.

[Pilot]

can you post a brand name and type of the material please ....