Bayer Plastics Makrolon Polycarbonate – Still UL approved?
The world of polycarbonate sheet has changed and evolved over the last several years. Most manufacturers have changed their formulation, and most new formulations no longer meet the tough UL certification ratings for flammability. Many manufacturers now do not rate their materials on the UL 94 series tests at all. Most suppliers don’t even meet the rating of UL 94 HB (which means it will burn horizontally!). The UL 94 V-0 means that when tested, the material did not burn vertically and was self extinguishing. In other words, it does not burn, puts itself out and will not add to the combustion. Bayer Material Science, formerly known as Sheffield Plastics, still certifies their materials to this high rating, and have a range of materials that can meet your requirements.
Bayer Material Science produces standard General Purpose Polycarbonate as Makrolon® GP, which meets the UL 94 HB rating. The next grade is their Makrolon® GP-V which carries the UL 94 V-0 at .210″ and thicker. They also have a superior grade called Makrolon® FI, and it meets the UL 94 V-0 at the thickness of .060″ and an amazing UL 5VA at .118″ and thicker.
Since the beginning of Polycarbonate, originally invented by General Electric Plastics, the most common trade name has been Lexan®. Today, the Lexan® trade name is owned and produced by Sabic Polymers (they purchased all of G.E. Plastics). Sabic is one of the best resin manufacturers in the world, and many of their resins are used to make products we supply (ie: Noryl® and Ultem®). The second largest – well known manufacturer of polycarbonate resins has been Bayer (yes, the company that makes your aspirin), and several years ago they purchased Sheffield Plastics. Sheffield has been a world leader in the manufacturing of Makrolon® Polycarbonate sheet and sheet. Now under the Bayer umbrella, this material is now the best rated polycarbonate sheet in the market.
Makrolon Polycarbonate Sheets Take A Beating
Both of these polycarbonate sheets are very high impact (considered unbreakable), and are exceedingly transparent, has the look of transparent glass. As one of the only clear plastic materials that is high impact, polycarbonate in glazing applications are very tough, and can take numerous hammer blows without cracking or breaking. Also, one of the distinct differences between these materials is the UL rating. Here is a copy of the current (May 2013) data sheets for these two brands of material – Bayer Makrolon®_GP, Makrolon® GP-V, Makrolon® FI and Sabic Lexan® 9034. Review these pages, with extra focus on the ‘Flammability’ ratings of these materials. You will see that Sabic does not list the UL 94 specification (the USA standard for flammability) at all, and that the Bayer – Sheffield material does meet the UL certification in a variety of materials. While this just one rating, it should not be the only factor when considering a polycarbonate purchase, it is important if your project needs a flammability rating. Both manufacturers produce very high quality sheet, and without the masking you can’t see a difference.