Expert: George Maxwell - 8/31/2007

Question
QUESTION: what are the properties of polymethylmethacrylate?

thankyou

ANSWER: Thank you for your question.

PMMA, (now polymethyl-2-methylpropenoate) is the chemical name for Perspex: it's a transparent, strong plastic used where you need the see-through properties of glass without the risk of shattering (e.g. safety windows, street furniture and so on).

It's resistant to most forms of chemical attack, and is used to make food containers and laboratory ware. It's even used in medical implants (particularly bone-filling materials).

It is a thermoplastic material: it will soften when heated, and melts at about 130 degrees centigrade. Above that, it tends to decompose, and will catch fire at about 450 degrees centigrade.

It is made from crude oil products, and is not biodegradable, so its future as a long-term resource is uncertain.

Hope this helps: please let me know if you need more detail on any of these points.


---------- FOLLOW-UP ----------

QUESTION: thankyou very much for your answer. can you please tell me some common uses of PMMA?

thankyou for you time

Answer
Thanks for the follow-up.

Perspex uses fall in to two categories:

1) Where you're using its translucency
e.g.

Making covers for signs, lights and similar.
Making lenses for cameras etc.
Making some types of window (e.g. aircraft windows)
Making safety screens (e.g. for chemistry labs): though these also use polycarbonate

2) Where you're using its strength and resistance to chemical attack.
e.g.

Making Acrylic Cement for filling and setting bones.
Making kitchenware (e.g. microwaveable plastic food containers).
Making non-flexible piping and tubing for specialist applications (PVC is used in everyday tubing, because it's cheaper).

As Perspex can be coloured, it is also used in:

Toys.
Moulded furniture (particularly baths and sinks).
Small mounded plastic items (e.g. some pens, trays, storage boxes and so on).

Hope this helps, thanks again.