Reinforced plastic continued glass content

Many fibers are used in laminates and reinforced plastics. The type of fiber used will depend on the cost, the properties required, and the nature of the polymeric system. Although glass fiber is the most common reinforcement, many others are used. Fiber reinforcements can also come in many forms such as discontinuous fibers, continuous fibers, mat and fabric. Fiber content is the amount of fiber present in reinforced plastics and composites, usually expressed as a percentage volume fraction or weight fraction. 

E glass—a calcium aluminosilicate with less than about 2 wt% alkali developed in the 1930s for electrical insulation applications. It has good electrical resistivity because of its low alkah content. Because of its excellent mechanical properties, its use has spread, particularly for glass-reinforced plastics. (Over 90 percent of all continuous-filament fiber is E glass.) However, it has poor acid durability. 

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