Plastics Replacing Glass for New Car Windows

For many new cars, traditional window glass may soon be replaced by light weight plastics. Formally known as polycarbonate glazing, these plastics windows are already starting to appear in a handful of small vehicles coming onto the market today, such as the 2014 Fiat 500L, and some industry insiders believe that the material could become standard in the near future. Even large brands like Ford are hard at work testing and developing the material in hopes of bringing it into implementation.

Weight is the plastic’s most attractive attribute; as much as 50 pounds could be stripped from a vehicle if its glass windows were replaced. In a typical vehicle, the glass accounts for as much as 100 pounds, when combined with the housings and mechanics that hold the windows in place. With the plastic alternative, not only do the windows themselves weigh less, but fewer parts are needed to attach them into a car. With this reduction, a vehicle could see noticeable gains in fuel economy, among other benefits. Automakers could even offset the weight with stronger and heavier safety features to increase occupant protection without increasing overall curb weight.

“The technology is now at the point where it is ready for mass-scale production,” says V. Umamaheswaran, global marketing director for the automotive department of SABIC’s Innovative Plastics business. “It’s not just weight savings [either], it’s hugely the styling implications and the aerodynamics.” Being a strong synthetic material, the plastic could be molded into any number of shapes, expanding design possibilities, further increasing safety and fuel economy potential.

Other iterations of the material are already being used in other areas of the automotive industry today, as 95% of all vehicles using polycarbonate glazing to cover their headlights. The transition into window panels would therefore be a relatively straightforward one. To be used for windows however, the plastic would need to meet strict scratch resistance requirements, and must be able to withstand the heat from defrosters in the winter months. An ultraviolet protection would also be needed to preventing yellowing and clouding over time.

For the foreseeable future, these plastic windows would be used largely in fixed and rear windows, along with panoramic sunroofs. Before the material can be used for more essential uses like door windows or front windscreens, more research, testing, and development is needed to ensure that it can handle its tasks with the same effectiveness as glass. The crack-proof and shatter-proof qualities of the plastic make is difficult for rescue personnel to reach victims in the event of an accident, as an example.

Cost is another roadblock facing production today, as the plastic windows can cost as much as twice that of glass. Upon reaching mass implementation however, costs should drop significantly, according to Umamaheswaran. In small numbers, materials can be costly to manufacture, but on a large scale, processes can become highly systemized and the cost per window created diminishes greatly. Ford has also launched a 10,000 hour environmental durability test to examine the effects of long term use, and if all goes well, polycarbonate glazing could find its way into your next vehicle.