Bullet-resistant polycarbonate

Bullet-Resistant Polycarbonate. Bullet-resistant polycarbonate is listed by UL as resistant to super-power small arms in thickness of l in. or greater. In 0.125 in. thickness, polycarbonate is rated as burglar-resistant. 

Polycarbonates are mainly used as a glazing material in construction (transparent roofing, impact-resistant glazing, sheet and for structural parts in building and construction). Greenhouses and the dome of the Sydney Olympic stadium all have PC sheet glazing. PC sheets are virtually unbreakable (bullet resistant windows, protective PC glazing panels). PC resins and BPA are known to be safe and they pose no health risk to humans. 

Polycarbonates are condensation copolymers formed by the reaction of carbonic acid with compounds such as bisphenoi A (Figure 15-31). This reaction forms the polycarbonate termed Lexan. Polycarbonates form clear, tough plastic materials that, if thick enough, can even stop bullets. Consequently, polycarbonate is often used in eye protection, as a scratch-resistant coating for eye glasses, and in bulletproof windows. 

Polycarbonate was invented in 1953 in the United States at GE Plastics and at about the same time in Germany at Bayer. GE marketed the polymer as Lexan and Bayer as Makrolon . In 2007, GE sold its plastics business to SABIC (Saudi Basic Industries Corporation), but the Lexan name is still used. About 30 years after the original invention, Dow Chemical Co. began offering polycarbonate under the name Cahbre . Polycarbonate is an amorphous polymer and has excellent clarity, dimensional stability, and toughness. It is used for bullet-resistant windows and automotive headlamps. 

Most laminated safety glarings are glass—PVB—glass tdlayer composites, but bullet- and projectile-resistant laminates. Laminates for other specialty uses maybe made with more than three layers. In addition to glass, poly(ethylene terephthalate) (PET), acryUc, and polycarbonate stmctural components (92) are used in specialty laminated glaring products. 

Polycarbonate It is a tough, transparent plastic that offers resistance to bullets and thrown projectiles in glazing for vehicles, buildings, and security installations. It with stands boiling water, but is less resistant to weather and scratching than acrylics. It is notch-sensitive and has poor solvent resistance in stressed molded products. Use includes coffee makers, food blenders, automobile lenses, safety helmets, lenses, and many nonburning electrical applications. 

Lexan is a tough polycarbonate used to make molded articles and also for impact-resistant shields, including bullet-proof glass. ... 

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