Over-molding for nylon

[hexane]

We want to manufacture a product with 2 type of plastic with diferent hardness by over-molding process. The substrate would like to be nylon, but it is hard to find the material(another plastic) which has a good adhersion with nylon for over-molding. Can you give me a hand for that?

 

[patprimmer]

If you want a softer material for over moulding, polyurethane will adhere to nylon 6 in over moulding.

If you want harder, Glass Filled Nylon can be moulded over unfilled

Bayer has a technical data sheet on the process.

I will see if I can find my copy and e-mail direct.

Regards
pat pprimmer@acay.com.au
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[vonbad]

Hexane,
In a different life, I worked on the same issue. We were overmolding a nylon insert with pvc. Our system was a hand operation. We found the best way to get a solid adhesion between the two parts was to use an adhesive on mylon just prior to pvc overmolding. If you are in a fully automated process this may not be applicable

Regards
Ted

 

[aspearin1]

If overmolding in a two-stage process (i.e. two different molds, you could incorporate cavities into your nylon part, which would be filled with the overmold plastic. This would at least give a mechanical bond. I'm not sure how well it would work in a single two-shot stage process.

ChemE, M.E. EIT
"The only constant in life is change." -Bruce Lee