Attaching foam to plasticized PVC

[tffy]

Hey guys - have a question for you... a product that I am developing has an extruded length (32" long) of plasticized PVC covered by foam (not sure exactly what formulation is being used now by subcontractor) – but whatever is required/suggested can be obtained.

The profile of geometry in question is attached with PVC shown in black and foam in gray.

The question is – what’d be the easiest and best way to "weld" these two parts together? Currently 3M 467MP adhesive transfer tape is being used – because the bond has to take at least 250F temperature, and a margin of safety on top of that is nice – but an issue still exists – the attachment is a bit too soft, flexible, and the tips of the foam (which is cut out of a flat sheet) 'fly up' and out of 'containment slots' with significant deformation. Any suggestions for what chemicals that might create a no-fail bond (the word weld again comes to mind) between the two surfaces here?

Thanks a lot, everyone.

-Gene Gisin

 

[tffy]

Oh, and

is the picture referenced in the message above.

 

[btrueblood]

Use a foamed pvc and solvent bond it to the other part?

 

[tffy]

Thanks for the reply, sir. I will investigate that option, but I believe that foamed PVC is unlikely to provide enough resistance in normal usage - being either too hard or too brittle.

Thank you, however!

 

[btrueblood]

Err...no. PVC can have widely varying modulus depending on how much plasticizer (I think) is in the mix. Soft PVC (vinyl rubber) foam is available from McMaster.com for instance.

 

[tffy]

You are right. Thanks again! I'm pursuing this lead, with some good results from initial tests. Weld-on P-68 Primer (just primer, not even glue!) seems to glue PVC foam to reasonably heavily plasticized PVC quite well.