Naked Science Forum

Non Life Sciences => Chemistry => Topic started by: neilep on 22/08/2007 21:37:04

Title: Acrylic Glass Versus Real Glass
Post by: neilep on 22/08/2007 21:37:04
What's the advantage of Acrylic Glass over real glass and vice-versa ?

Real glass came first...and I presume Acrylic glass was made to serve a need yes?


REAL GLASS
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NOT REAL GLASS
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Title: Acrylic Glass Versus Real Glass
Post by: another_someone on 22/08/2007 21:59:28
Weight (plastics are lighter), and impact resistance.
Title: Acrylic Glass Versus Real Glass
Post by: neilep on 22/08/2007 22:29:58
Weight (plastics are lighter), and impact resistance.
THANKS GEORGE (Thanking you many times today )


What about the manufacturing ?

...which is greener ?...economically more viable ?
Title: Acrylic Glass Versus Real Glass
Post by: another_someone on 22/08/2007 22:48:43
Plastics are almost always going to be cheaper to produce, and their light weight makes them cheaper to transport.

Plastics generally take less energy to make, but glass is easier to recycle (if one ignore transportation costs).

In general we have seen a continual decline in the use of glass as a packaging material, because of cost of production, but at least as much because of the cost of transportation (due to weight).  Glass is also impossible to incinerate.

Glass has its advantages, because of its hardness (scratch resistance - although some plastics are improving in that regard), optical qualities, and relative inertness.
Title: Acrylic Glass Versus Real Glass
Post by: eric l on 23/08/2007 13:10:48
Weight (plastics are lighter), and impact resistance.
... and transparency (same thickness "real" glass will absorb more light than acrylic) and more easily moldable in different shapes (lower working temperature for moulding).  But acrylic is less scratch resistant and scratches reduce clearness of a pane or lens. 
Title: Acrylic Glass Versus Real Glass
Post by: Karen W. on 23/08/2007 13:49:22
Isn't the acrylic less likely to shatter?
Title: Acrylic Glass Versus Real Glass
Post by: lightarrow on 23/08/2007 15:54:35
Isn't the acrylic less likely to shatter?
Yes, this is another advantage: more safety.
Title: Acrylic Glass Versus Real Glass
Post by: Karen W. on 23/08/2007 20:42:46
Thanks Alberto I suspected as much!
Title: Acrylic Glass Versus Real Glass
Post by: Bored chemist on 23/08/2007 20:56:02
Depending on what optical property you want acrylic or ordinary (silicate) glass can be better.
If you want to make lenses then silicate glass gives a large range of dispersion and refractive index to work with, but if you want a window the acrylic can do a better job. It has a lower refractive index than most silicate glasses so it reflects less light. Less reflection means more light gets through. Also acrylic can be made with better UV transparent than cheap silicate glass. (If you really want good UV transparency in a glass, you use fused silica).
Title: Acrylic Glass Versus Real Glass
Post by: neilep on 23/08/2007 21:07:58
Plastics are almost always going to be cheaper to produce, and their light weight makes them cheaper to transport.

Plastics generally take less energy to make, but glass is easier to recycle (if one ignore transportation costs).

In general we have seen a continual decline in the use of glass as a packaging material, because of cost of production, but at least as much because of the cost of transportation (due to weight).  Glass is also impossible to incinerate.

Glass has its advantages, because of its hardness (scratch resistance - although some plastics are improving in that regard), optical qualities, and relative inertness.

THANK YOU for elaborating George.

 Does Acrylic glass though produce more caustic fumes during fabrication ?
Title: Acrylic Glass Versus Real Glass
Post by: neilep on 23/08/2007 21:09:46
Weight (plastics are lighter), and impact resistance.
... and transparency (same thickness "real" glass will absorb more light than acrylic) and more easily moldable in different shapes (lower working temperature for moulding).  But acrylic is less scratch resistant and scratches reduce clearness of a pane or lens. 

THANK YOU ERIC, so we won't see car windows being made from acrylic any day soon !

I appreciate your answers very much.
Title: Acrylic Glass Versus Real Glass
Post by: neilep on 23/08/2007 21:10:46
Isn't the acrylic less likely to shatter?
Yes, this is another advantage: more safety.

THANKS ALBERTO.....I am learning a lot thanks to you people.
Title: Acrylic Glass Versus Real Glass
Post by: neilep on 23/08/2007 21:13:28
Depending on what optical property you want acrylic or ordinary (silicate) glass can be better.
If you want to make lenses then silicate glass gives a large range of dispersion and refractive index to work with, but if you want a window the acrylic can do a better job. It has a lower refractive index than most silicate glasses so it reflects less light. Less reflection means more light gets through. Also acrylic can be made with better UV transparent than cheap silicate glass. (If you really want good UV transparency in a glass, you use fused silica).

THANK YOU VERY MUCH BORED CHEMIST.

SO, do you think it is possible then to fabricate a car window from Acrylic ?....well..I suppose the answer is yes but will it have a limited life span as it will scratch easier ?

Your guidance is most appreciated
Title: Acrylic Glass Versus Real Glass
Post by: daveshorts on 24/08/2007 13:54:37
If you were making car windows out of a plastic you would probably use polycarbonate, which is really tough, acrylic (perspex) will snap, but you have to work really hard to break polycarbonate. They are also coming up with coatings for it which mean it is more scratch resistant.

One of the first uses for perspex was for bubble canopies on aeroplanes like  spitfires.
Title: Acrylic Glass Versus Real Glass
Post by: Karen W. on 24/08/2007 14:13:57
Yeah, our sun roof in our blazer had been replaced with a piece of heavy duty acrylic sheeting. Bit as soon as it was hit with a basketball it split 4 ways. Although it did not shatter! which did offer us some happiness in the knowledge that we were not hurt! LOL
Title: Acrylic Glass Versus Real Glass
Post by: eric l on 24/08/2007 15:01:36
If you were making car windows out of a plastic you would probably use polycarbonate, which is really tough, acrylic (perspex) will snap, but you have to work really hard to break polycarbonate. They are also coming up with coatings for it which mean it is more scratch resistant.

One of the first uses for perspex was for bubble canopies on aeroplanes like  spitfires.

Polycarbonate is the stuff they use for the iuter shell of crash helmets.  It is surely tough
Title: Acrylic Glass Versus Real Glass
Post by: Karen W. on 24/08/2007 15:10:36
If you were making car windows out of a plastic you would probably use polycarbonate, which is really tough, acrylic (perspex) will snap, but you have to work really hard to break polycarbonate. They are also coming up with coatings for it which mean it is more scratch resistant.

One of the first uses for perspex was for bubble canopies on aeroplanes like  spitfires.

Polycarbonate is the stuff they use for the outer shell of crash helmets.  It is surely tough

So Poly carbonate is a bit different then the acrylic eh?? Tougher??