Ask A Scientist Materials Science Archive

name         Pete
status       other
grade        other
location     GA

Question -   What type of plastic can be "welded" with acetone?
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Thermoplastic acrylic plastics (Plexiglas) can be "welded" with acetone,
but that is not the solvent of choice because it is too volatile. There
are solvent blends available at hobby, art, and/or glass stores that work
better -- forming a stronger bond.

Vince Calder
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Pete,

The "welding" that you speak of is really just the action of dissolving 
some of the plastic and allowing the pieces to recrystallize or reform 
across pieces - forming a physical bond. Actually quite a few commercial 
plastics are soluble (or at the very least swollen) by acetone. 
Unfortunately, it is difficult to say exactly what plastics can weld since 
formulations and manufacturing processes applied to the plastic can impart 
a wide range of properties on the plastic part. In general, most 
polystyrene formulations can be dissolved by acetone (you can easily test 
this by applying just a little bit of acetone onto polystyrene foam packaging or 
on the clear plastic windows of envelopes).

Roberto Gregorius
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