To begin with, let's
settle the naming issue.
Plexiglas® and
Lexan® are trademarked brand names (belonging to
Roehm
& Hass and
GE
Plastics,
respectively). Each belongs to a different family of plastics,
Plexiglas being an acrylic and Lexan being a polycarbonate. They are
quite different materials, and each has pros and cons.
As such, we're going
to give each its own section to explain their strengths and
weaknesses.
Plexiglas ®
- aka Acrylic,
Lucite, Perspex and Polymethyl
methacrylate
When compared to
glass, plexi is generally described as more optically clear ( none of
the green tint commonly seen in glass ), more impact resistant (about
10 times tougher) and it weighs about half as much as glass does.
It's also quite easy to bend using a little heat, and cut edges can
be polished easily. Using the right product, small scratches can be
polished out of a plexiglas sheet. Pieces can also be glued together
using cyanoacrylate cement (superglue).
Plexi is used in
architectural glazing, large aquariums, and in many kinds of
heat-formed items (furniture, store displays, curved windows in
aircraft). It is considered a safer alternative to common glass in
high risk areas, such as the 'glass' around hockey rinks. It is also
commonly used in the sign industry. Plexiglas powder is also used as
a dispersant for ceramic powders to stabilize colloidal suspensions
in non-aqueous mediums. I have no idea what that means, but it sounds
important.
Cons -
Plexi scratches. It can be chipped or cracked if dropped or hit hard
enough. It's more expensive than glass, and has a tendency to build
up a static charge which attracts dust. Under the right conditions
(or the wrong conditions, depending on your perspective) Plexiglas
will burn.
Lexan ®
- aka Makrolon,
Makroclear and Polycarbonate
Lexan is a step up in
safety from plexiglas. It's more impact resistant than common glass
or plexi (about 30 times tougher than glass) and almost as optically
clear as plexiglas. While a touch heavier than plexi, it is still
lighter than glass. Thermoforming Lexan is a bit harder, but it is
much easier to cut and drill, and with the right equipment it can be
formed at room temperature just like metal. It doesn't crack or chip
easily. Lexan is actually marketed as '
Virtually
Unbreakable.'
Lexan is used in
places where impact resistance is critical. Items such as safety
lenses, police riot shields and visors, instrument panels and
headlamp lenses. A lot of bullet proof glass is actually very thick
Lexan. Lexan is also commonly used for plastic drink bottles and CDs
/ DVDs.
Cons -
Lexan scratches. Very easily. It's also more expensive than plexi or
glass. Except for specially formulated UV resistant varieties, Lexan
will yellow over time. Under high heat conditions, Lexan will melt