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Finish that can be applied to a plastic surface to make it inert

2006

Is there some sort of finish that can be applied to a plastic surface to make said surface inert...seal against bleed through of possible chemical residues?

I want to purchase high density polyethylene large diameter pipe (2" thick and 28" diameter) recycled from a copper mine. It will possibly have had sulfuric acid pumped through it and possibly metal salts in solution. I want to grind out 1/8 to 1/4 inch of material from the inner surface and apply a chemically inert surface to trap any small amounts of materials possibly left behind. This resurface should not off-gas or be toxic in anyway.

Thank you for any suggestions you can give.

James W. Williams
James Wade Williams, P.C. - Mesa, Arizona

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Whatever you sealed it with, if you could perfectly seal it, could eventually erode or corrode away, releasing whatever it was that was sealed in.

If this is a critical application, forget it. But if it's merely your reasonable expectation that the pipe not contaminate anything, then washing it thoroughly, removing a 1/4 inch, visually inspecting for cracks, washing again, and testing for contaminants sounds workable if the pipe hasn't been badly abused to where it might have cracks running deep into it.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2006