Polycarbonate is an excellent engineering polymer. PC has a good balance of properties, with good temperature resistance, excellent impact resistance and also superb optical properties.
“Hardie Polymers are a delight to deal with, with very friendly, knowledgeable and helpful staff.
Their ever-increasing range of products and their ability to source unusual grades is always greatly appreciated, and allows us to pass on material developments to our customers.
We would recommend them to all.”
Broanmain Plastics, Dorking
Polycarbonate is tough, durable, strong, hard, rigid, has good cold-temperature impact strength (up to – 100°C) is clear as glass, non-toxic, takes colour pigmentation well, has low moisture absorption and good weather resistance.
Resistant to oils, fuels, diluted acids, and alcohols.
Not resistant to strong acids, alkaline solutions and benzene
Polycarbonate is commonly used in electronic applications that take full advantage of its collective safety features. With good electrical insulation properties along with its good heat-resistant and flame-retardant properties, it is widely used in various products associated with electrical and telecommunications equipment.
Other applications are numerous and include lenses, automotive lighting, CD discs, safety helmets, electrical components, mobile phones, medical products, domestic goods, aerospace and defence applications.
With ‘light-weighting’ a major driver now within the automotive sector, car manufacturers have seen the benefits of changing from glass to polycarbonate for headlamp lenses.
Polycarbonate , so called since it is a polymer containing Carbonate groups.
Bis phenol A polycarbonate (PC) is a linear chain polymer with a stiff backbone (benzene rings) and methyl side groups, resulting in a high glass transition temperature (Tg) of 150 °C.
The structure is too bulky to crystallise and PC behaves as an amorphous thermoplastic. As such it is rigid and strong but, unexpectedly, it is ductile and is one of the highest impact resistant thermoplastics.
As an amorphous thermoplastic, PC is transparent but soluble in moderately polar organic solvents.
The high Tg allows PC to be used at temperatures in excess of 120 °C.
PC is flame retardant and will extinguish when removed from the flame. It burns with a luminous yellow and a smoky flame and will tend to char and blister. It gives off no particular odour.
Compared to PA and PET, polycarbonate is self-extinguishing and so performs better in fire situations.
Density – 1.2g/cm ³
Pre-Drying – 3 hours at 120 °C in a dehumidifying hot air drier
Melt Temperature – 280-310 °C
Mould Temperature -80 -110°C
Shrinkage – 0.6-0.8% and with glass filled grades 0.2-0.4%
Trade Names And Manufacturers
SABIC – Lexan
Covestro – Makrolon
Teijin – Panlite
LG Chem – Lupoy
Mitsubishi Plastics – Iupilon
Idemitsu – Tarflon
Chi Mei – Wonderlite
Polyram – Ramtough
Romira – Rotec
Trinseo – Calibre
Samyang Kasei – Trirex
Kotec – Carbotex
Hardie Polymers can help source grades from all of the above manufacturers
Although Polycarbonates were first discovered back in 1898 by a German scientist working at the University of Munich called Alfred Einhorn, it was not until much later in 1953, when Hermann Schnell working for the German chemical company Bayer in Uerdingen, patented the first linear polycarbonate. The brand name Makrolon was registered just a couple of years later in 1955.
Also in 1953, and bizarrely only one week after the invention at Bayer, across the Atlantic, a Mr Daniel Fox of General Electric in Schenectady, New York, independently synthesized a branched polycarbonate.
After some legal wrangling, the patent priority was eventually resolved in 1958 in Bayer’s favour, and they then began commercial production of polycarbonate under their new trade name Makrolon.
General Electric (GE) then began production of their polycarbonate under the name Lexan in 1960. To this day they remain the two predominant trade names in the field of polycarbonates. Both are available from Hardie Polymers.
More about Polyamides
Articles by Dr Charlie Geddes
Our longstanding partnerships allow us to specialise in sourcing and compounding most grades of engineering polymers. All brand names listed are trademarks of the manufacturers and we are not an authorised distributor for these manufacturers. We only supply prime grades in original packaging with the manufacturers documentation.
® – Trademarks owned or used by the producers.
™ – Registered in the U.S. Patent and Trademark Office (status in the U.S. only, registration status in other geographies may be different)