Annex XI: Automotive Glazing

1. Overview of scope
The objective of this annex is to develop environmental-friendly materials for automobile application, including lightweight glazing, replacing glass with polymeric glasses. This Annex intends to develop material specifications for automotive glass replacement materials, test method development & standardization of test methods.

2. Annex Participants
Korea: Dr. Yeo Seong Yoon, KATECH
China: Prof. Ping Jin, Shanghai Institute of Ceramics, CAS

3. Activity/Accomplishments
Polymeric glazings are desirable because of their ability to reduced weight by up to 40%-50%; improve thermal insulation properties, as compared with the original glass material. This improves fuel economy and provides enhanced optical properties as well improved safety due to higher impact resistance. The material issues are basic polymer formulation, functional coatings, and processing technology. With the automotive industries worldwide embarking on fuel economy improvement, lightweighting has become one of the major focuses. Replacing glass with polycarbonate-based materials and various coatings to improve the optical and UV resistance is the main thrust of this Annex. Since this is a new area, test methods and standards are lacking and it is also the objective for this Annex to address.

Coating on Polycarbonate
Hard coating was made on a polycarbonate plate using a sol-gel process with silicates for automobile glass. Methylated polymer and tetraethoxysilane (TEOS) were used to form a coating solution. The coatings on the polycarbonate plate were deposited using a sol-gel process. Poly (methyl methacrylate) was coated on the surface of polycarbonate in order to improve adhesion property. The optimum conditions and formulation to obtain excellent physical properties of the coating were determined. The hardness, abrasion resistance, and surface uniformity were found in the coated polycarbonate surface.

Fig. 1. Coating process concept of Sol-gel method on polycarbonate

Fig. 2. Coating on Thermoplastic polycarbonate

4. Significance and Impact
The vehicle manufacturers are challenged to develop the light-weight advanced materials to comply with government regulations as well as meet consumer needs. The glazing materials such as high performance glasses and plastics contribute to lowering pollutant emission thanks to the weight reduction and improved energy efficiency. Annex XI will provides weight reduction more than 40% when new glazing is used. Moreover, design flexibility allows complex and aerodynamic shape.