CR-39

Poly(allyl diglycol carbonate)

Polymer structure
Names
Other names
2,5,8,10-Tetraoxatridec-12-enoic acid, 9-oxo-, 2-propen-1-yl ester, homopolymer
Identifiers
Abbreviations PADC
Properties
Density 1.31
1.498
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Diallyl diglycol carbonate

Monomer structure
Names
IUPAC name
2-(2-prop-2-enoxycarbonyloxyethoxy)ethyl prop-2-enyl carbonate
Other names
allyl diglycol carbonate (ADC); diethyleneglycol bis allylcarbonate
Identifiers
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
A piece of CR-39 manufactured for radiation detection

Poly(allyl diglycol carbonate) (PADC) is a plastic commonly used in the manufacture of eyeglass lenses alongside the material PMMA (polymethyl methacrylate). The monomer is allyl diglycol carbonate (ADC). The term CR-39 technically refers to the ADC monomer, but is more commonly used to refer to the finished plastic.

The abbreviation stands for "Columbia Resin #39", which was the 39th formula of a thermosetting plastic developed by the Columbia Resins project in 1940.[1]

The first commercial use of CR-39 monomer (ADC) was to help create glass-reinforced plastic fuel tanks for the B-17 bomber aircraft in World War II, reducing the weight and increasing the range of the bomber. After the war, the Armorlite Lens Company in California is credited with manufacturing the first CR-39 eyeglass lenses in 1947. CR-39 plastic has an index of refraction of 1.498 and an Abbe number of 58. CR-39 is now a trade-marked product of PPG Industries.[2]

An alternative use includes a purified version that is used to measure ionising radiation such as alpha particles and neutrons.

Although CR-39 is a type of polycarbonate, it should not be confused with the general term "polycarbonate", a tough homopolymer usually made from bisphenol A.[3]

  1. ^ "Optical Products". Corporateportal.ppg.com. Archived from the original on 2009-06-13. Retrieved 2012-09-15.
  2. ^ "Optical Products". Corporateportal.ppg.com. Archived from the original on 2006-04-19. Retrieved 2012-09-15.
  3. ^ "A Field study" (PDF). Dtic.mil. Archived (PDF) from the original on October 2, 2012. Retrieved 2012-09-16.