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Subject: Re: [Homebrew_PCBs] Isopropyl Alcohol 90%

From: "Stefan Trethan" <stefan_trethan@...>
Date: 2006-11-28

On Tue, 28 Nov 2006 13:44:32 +0100, AnaLog Services, Inc.
<wireline@...> wrote:

> Most peculiar. I originally noticed this with denatured alcohol. The
> denaturing agent is usually methanol. I ∗THINK∗ I have seen the same
> effect
> with PGA ethanol, but now I am questioning my sanity. I will do some
> experimenting down in the lab later today.
> I did come across a mention of 0.37% solubility of polystyrene cup
> material
> in PGA, but not much else with a web search.


Polystyrene foam cups are virtually non-existent here. I can't remember
ever seeing one in my life.
Coffee machines use polystyrene cups, but not foam, they are vacuum formed
sheet with a rolled edge, or some cardboard polyethylene composite
material.

But still, expanded or extruded polystyrene should be the same all around
the world, since it is shipped as packing material everywhere. My ethanol
did not do anything to that, or vacuum-formed sheet polystyrene cups.
Acetone or laquer thinners will eat all that though.

ST