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Allan Waterfall
04-01-2009, 04:25 AM
Has anyone had any success gluing rubber to polypropylene ?

I'm thinking of making a special wheel for the model speed bike I run and thought of gluing a rubber tyre cap on,I'm having trouble with the tyre ballooning and leaving the rim on the wheels that are normally used for racing.
http://www.rcgroups.com/forums/attachment.php?attachmentid=2433974

Allan

Evan
04-01-2009, 05:37 AM
Loctite Glue for all Plastics.

It works on PTFE just fine and is advertised to work on ALL plastics.

http://metalshopborealis.ca/pics/tglue.jpg

JABautsch
04-01-2009, 07:12 AM
Try this web site. It has recommendations for gluing all types of things together.

http://www.thistothat.com/

ckelloug
04-01-2009, 11:24 AM
I've never tried gluing to polypropylene but my experience with polyethylene is that epoxy won't stick to smooth polyethylene.

Polyethylene and polypropylene have very low surface energies. It's hard to get stuff to stick to them well because nothing wants to wet them. If this were production, you could probably make the glue of your choice stick to the polypropylene with a corona discharge treatment. I'd assume that the glue that works has a solvent component that dissolves the surface of the polypropylene but that's just a guess.

Good luck.

aboard_epsilon
04-01-2009, 11:33 AM
doesn't polypropylene have some sort of wax in it ..if it has you're looking at the impossible .

all the best.markj

Evan
04-01-2009, 11:39 AM
I have no idea how the Loctite product works but it does work on PTFE very well. The two blocks in the image were some test pieces that I glued with the product. After allowing plenty of time to set I subjected it to a highly scientific and well instrumented shear test. I clamped one part in a vise and with a crescent wrench estimated how much torque I needed to apply to break the bond. Doing the math I estimated about 2000 psi shear required. What surprised me was that it tore away a thin layer of the PTFE instead of the glue failing to adhere to the surface. Also surprising to me is that my estimate was pretty close to the actual shear strength of PTFE at 2400 psi.

BTW, it isn't difficult to make a corona discharge device.

Allan Waterfall
04-01-2009, 02:38 PM
As I said in the opening post,I need to stick rubber to Polypropylene,I've since found out that loctite do a special primer for polypropylene to allow rubber to be stuck to it,so I'll probably go with that and use the black cyano to stick it.

Allan