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Aluminum to polycarbonate bonding

 

I'm trying to bond an aluminum fitting to a flat piece of polycarbonate. What would be an appropriate adhesive for this. I would like the bond to be airtight and fairly strong.

Thanks,

Marty Verbic
engineered materials - Urbana, Illinois

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Marty,

Although I was nigh on 40 years in the thermoplastic (fabricating/acid resistant) industry, I know nowt about Polycarb as it is not a good acid/alkali resistant material.

There may be a way if you consider that epoxy is nbg.

Any supplier of Polycarb would be able to tell you just what solvents (if any) they use. Then get some and in a tin mix up a solution of, say, 25% Polycarb with the solvent. Mix thoroughly.

The next step is to coat the PC with a heavy layer and immediately lay on top either a piece of coarse cloth or, preferably, some (glass) woven roving. Allow the bottom loops of the roving to become saturated. Then let dry. This may take a day or so. Now you have (or should have!) exposed glass loops which, with epoxy, will glue very satisfactorily to the aluminum.

A convoluted method maybe ... but this method was used with very great success (before bonding resins came on the scene) in order to 'bond' fibreglass to PVC and make 20 foot dia tanks, etc.

This maybe totally impractical in your case ... but then you didn't give any sizing or idea of how big these parts are. (for that matter most 'inquirers' don't give enough data).

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).