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Ted Mooney, P.E. RET
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Pmma authenticity test
2004
Hey all!
I machine stainless and other "bio-safer" materials and recently purchased some polymethly methacrylate, or so I have been told. The material seems to act different that other pieces of pmma I have, and I am suspicious that the material is not pmma, but pmmc (polymethly methylchloride) or some other plastic. Is there a test to confirm the item is methylmethacrylate? Any help is greatly appreciated!
Thanks!
owner /operator /machinist,etc... - Kelowna, B.C., Canada
Properties of PMMA (Polymethyl Methacrylate) such as Lucite® and Plexiglas® are given at www.matweb.com. Click on "Material Type" then under "Thermoplastic Polymers" select "Acrylic". I've never heard of a methyl chloride polymer ˜ perhaps you mean vinyl chloride. Comparing unfilled PMMA to rigid, unfilled PVC, the PMMA is clearer (transmits 92 % of visible light) and less dense (1.15-1.19 g/cc vs. 1.3). Also, PMMA burns relatively cleanly, while PVC emits an acrid black smoke containing hydrochloric acid.
Ken Vlach [deceased]- Goleta, California
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Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.
2004
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