Why Is Lexan Glass So Strong?

History

• The strength of the polycarbonate resin used in Lexan glass was first discovered by Dr. Daniel Fox of General Electric (GE) in 1953. Fox discovered that the soft and slimy resin once hardened displayed remarkable strength that took tremendous force to destroy. In 1955, GE applied for a patent for the polycarbonate resin at the same time as Bayer, a pharmaceutical company. A deal was then struck between the two companies, allowing the losing applicant for the patent to develop and sell the product, in addition to paying a royalty to the winning company for the privilege.

Origin

• Lexan glass is manufactured by SABIC Innovative Plastics. Despite its name, Lexan glass is not glass in the true sense, but a resilient form of thermoplastic derived from polycarbonate resin. The strength of Lexan glass is produced by combining carbonyl dichloride with bispehnol A. The combination of these substances causes a chemical reaction that results in the formation of the resilient polycarbonate polymer material.

Structure

• The polycarbonate material used in Lexan glass is categorized as an amorphous solid. This means the molecules contained within the material are not structured in a firm, latticed pattern, as they are in diamonds, ice, and many forms of metal. Amorphous solids can exist in both a rubbery and a glassy state. The point at which they change from the soft to the hardened state is known as their glass transition temperature. Once hardened, Lexan glass achieves its extreme force-resistant qualities.

Resistance Qualities

• Lexan products are usually shatter resistant and can rarely be broken. Due to its enhanced strength compared to other materials, Lexan glass can be made both thinner and lighter, yet still be immune to breakage. Lexan glass is highly resistant to extreme temperatures as well as extreme force. According to the SABIC Innovative Plastics website, Lexan glass can withstand temperatures of up to 212 degrees Farenheit (100 degrees Celsius) and as low as -40 degrees Farenheit (-40 degrees Celsius). It is also resistant to inclement weather and ultraviolet light.