Thermal Cure Adhesive that sticks to Polyimide film

[83118898]

hi,

Can someone recommend me a suitable glue that can be thermal cured (prob at less than 100 degree celsius) and can stick to polyimide film?

Also, it would be good if this glue can be commonly purchased and is safe for experiment testing in a lab without any gloves /ventilation.

I need a suitable glue just for some simple lab testing.

Thanks a lot.

 

[btrueblood]

Standard epoxy glues should work. You may want to lightly abrade the surface of the polyimide first.

 

[Compositepro]

Generally polyimide films do not bond well and require surface treatments or additives to improve bonding. Otherwise many adhesives will work. Strain gages are usually on Kapton film and there are adhesives made just for bonding these gages to subtrates.

 

[MintJulep]

From a guide to surface treatment for bonding published by Ciba adhesives:

Nylon (polyamide)
Degrease with detergent solution. Roughen by grit-blasting or with emery cloth (and degrease again).
Alternatively, for what are usually better results, prime with a mix of 100 g I&Redux K6 with 15 g para-toluene
sulfonic acid dissolved in 85 g ethyl alcohol.

Then epoxy should work fine.

 

[unclesyd]

I would give Reltek or Master Bond a call. Both companies of a variety of off the shelf products or can compound any type special purpose product as needed.

http://www.reltekllc.com/index.html

http://www.masterbond.com/

 

[Compositepro]

Nylon is a polyamide. Kapton is a polyimide. This is a very common oversight, however, the polymers are very different.

 

[btrueblood]

We had polyimide (Kapton) resistance heaters that were bonded to propellant lines for spacecraft; the glues used were just fancy grades of epoxy (fancy because they'd been tested for low outgassing, and had special high-thermal-conductance fillers). Other than abrading and cleaning/degreasing, we used no special primers that I recall, and the heaters generally stayed stuck. That's not to say that a primer isn't a good idea, especially if you are counting on a lot of stress transfer across the bond line. Our heaters were lightweight little things like a thick piece of tape, and were preformed to generally conform to the surface they were bonding to. The substrates and heaters would undergo qualification shock and vibration for typical spacecraft launch environments, thermal vacuum tests, and firing tests and performed at temperatures to around 180 F. 3M tried to sell us on their VHB acrylic adhesive tapes (this is what you get typically if you buy a sticky kapton tape, eg plater's tape), these adhesives generally worked, but would debond at the higher temperatures where the acrylic would soften. Buy a grade of epoxy rated to work at your worst-case temperatures, abrade and degrease both sides of the bond, clamp it in place and cure per the mfg. recommended cycle (hot cure epoxies generally give better performance, but if something else limits you to 100F, well, you're stuck...pun intended).