[ffindling]

Lexan is a polycarbonate resin thermoplastic which is a different material
from PMMA (polymethyl methacrylate) which is main component of Plexiglass,
Perspex, Acrylite, Lucite, Altuglas and other acrylics. Lexan was manufactured
by GE, but GE sold off their plastics division to SABIC (Saudi Basic Industries
Corporation) in May 2007. SABIC was formed by Royal Decree in 1976 as a
means of finding new ways to exploit Saudi Arabia's petroleum resources.
SABIC is now one of the top chemical companies in the world and is one the
leading producers of ethelyne glycol.
Although polycarbonate resins are considerably harder than acrylics, I think
the main impediment to its greater use in the automotive industry is that it
still scratches far more easily then glass. It probably would be possible to
engineer a laminated polycarbonate resin windshield with the same frangibility
properties as safety glass, but scratch resistance would still remain an
issue.

....Fred