CR-39 is transparent in visible spectrum and is almost completely opaque in the ultraviolet range. It has high abrasion resistance, in fact the highest abrasion/scratch resistance of any uncoated optical plastic. CR-39 is about half the weight of glass and index of refraction only slightly lower than that of crown glass, making it an advantageous material for eyeglasses and sunglasses lenses. A wide range of colors can be achieved by dyeing of the surface or the bulk of the material. CR-39 is also resistant to most of solvents and other chemicals, to gamma radiation, to aging, and to material fatigue. It can withstand the small hot sparks from welding. It can be used continuously in temperatures up to 100 °C and up to one hour in 130 °C.
In the radiation detection application, raw CR-39 material is exposed to proton recoils caused by incident neutrons. The proton recoils cause tracks, which are enlarged by an etching process in a caustic solution of sodium hydroxide.
The enlarged tracks are counted under a microscope (commonly 200x), and the number of tracks is proportional to the amount of incident neutron radiation.
Effect of alpha-particle energies on CR-39 line-shape parameters using positron annihilation technique.(Polyally diglycol carbonate )
Jul 01, 2006; Polyally diglycol carbonate "CR-39" is widely used as etched track type particle detector. Doppler broadening positron...