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Fiberglass composites are produced in the largest quantities and they consists of glass fibers (continuous or discontinuous), contained within a polymer matrix. The glass which is most commonly drawn into fibers is referred to as E-glass and its diameter usually ranges between 3 and 20 m. Glass is widely used as a fiber reinforcement material due to its:

1 a) facile processing into high-strength fibers from the molten state.

2 b) wide availability and its easy processability into glass-reinforced plastic.

3 c) ability to produce high specific strength composite when used as reinforcement in a plastic matrix.

4 d) its chemical inertness, which makes it extremely useful in corrosive environments.

In glass fibers, the surface characteristics are important attribute because even a single or minute surface flaw can significantly affect the tensile properties. Surface flaws can be incorporated with much ease by rubbing or abrading the surface with another hard material. The surface of glass which is exposed to the normal atmosphere even for short time interval tends to have a weakened surface layer which interferes with bonding to the matrix. The fibers are coated during drawing with a thin layer of a material that protects its surface from damage and other environmental interactions [6]. There are various limitations to GFRP materials. Although they have high strengths, still they are not very stiff and also do not display the rigidity which is crucial for some applications (airplanes and bridges). The GFRP materials can work perfectly below 200 °C; where after, most polymers begin to flow or to degrade. However, this working temperature can be extended to 300 °C by utilizing high-purity fused silica for the fibers and high-temperature polymers such as the polyimide resins. The fiberglass is utilized in a variety of applications such as automotive and marine bodies, plastic pipes, storage containers, and industrial floorings. In transportation industries the glass fiber-reinforced plastics can decrease the vehicle weight and boost fuel efficiencies.