What Is Shatterproof Glass

How does chemistry increase the resistance of glass to impact and shattering  

The shatterproof glass used in impact-resistant windows is actually not a glass material derived from silicon dioxide. Instead, shatterproof glass is a thermoset plastic or thermoplastic, i.e., a pliable material that is even easier to mold when hot. Shatterproof windows are made using a specific thermoset material known as polycarbonate of bisphenol A (or bisphenol A polycarbonate). This clear, 

General Electric markets the polycarbonate of bisphenol A as LexanJ I Similar bisphenol A polycarbonate sheets are marketed by Rohm and Haas as the product 

Polycarbonate is a generic term for the class of polymers consisting of long-chain linear polyesters of carbonic acid, H2CO3, and aromatic alcohols known as phenols that possess two hydroxyl groups. 

The synthesis of polycarbonate of bisphenol A begins with the reaction of bisphenol A and sodium hydroxide to obtain the sodium salt of bisphenol A, as in Fig. 14.4.3. The sodium salt of bisphenol A is then reacted with phosgene to 

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