View Single Post
  #2   Report Post  
nestork nestork is offline
Senior Member
 
Posts: 2,498
Default

Quote:
Originally Posted by Deodiaus View Post
Has any modern day alchemists tried and succeeded to reconstitute PVC cement which got wet. THis is probably hard as it involves a complex chemical reaction with water which might be very difficult to drive backwards.
But then, I am sure that I am not the only one who has had this happen.
No, there's no complex chemistry to it.

This web page offers a link to the MSDS form for Oatey Regular Clear PVC Cement:

PVC Regular Clear Cement | Plastic Pipe Cements & Primers | Oatey

If you click on the MSDS link, you'll find that PVC cement consists of a mixture of solvents, typically:

15 to 40 percent tetrohydrofuran - Tetrohydrofuran is a solvent that dissolves PVC

10 to 20 percent PVC resin

10 to 20 percent acetone - which is what nail polish remover is

10 to 30 percent Methyl Ethyl Ketone, which is chemically very similar to acetone, and

7 to 13 percent cyclohexanone, which is basically benzene with an oxygen double bonded to one of the carbon atoms.

Really, the tetrohydrofuran just dissolves the PVC, and as it and the other solvents evaporate from the joint the plastic reforms with the new PVC resins being incorporated into the joint. Physically, it's very much like melting ice and then letting it refreeze.

It's the tetrohydrofuran that does all the work here, and any place that makes PVC windows will have some they can sell you or at least know where you can get it. If your PVC cement is just thick rather than hard, I would just add some tetrohydrofuran to thin it out. If it's hard, what you have is a hunk of PVC plastic, and you may as well chuck that in the garbage.

Last edited by nestork : June 9th 14 at 01:41 AM