Fiberglass, (also called fibreglass and glass fibre), is material made from extremely fine fibers of glass. It is used as a reinforcing agent for many polymer products; the resulting composite material, properly known as fiber-reinforced polymer (FRP) or glass-reinforced plastic (GRP), is called "fiberglass" in popular usage. Glassmakers throughout history have experimented with glass fibers, but mass manufacture of fiberglass was only made possible with the invention of finer machine tooling. In 1893, Edward Drummond Libbey exhibited a dress at the World's Columbian Exposition incorporating glass fibers with the diameter and texture of silk fibers. This was first worn by the popular stage actress of the time Georgia Cayvan.

What is commonly known as "fiberglass" today, however, was invented in 1938 by Russell Games Slayter of Owens-Corning as a material to be used as insulation. It is marketed under the trade name Fiberglas, which has become a genericized trademark. A somewhat similar, but more expensive technology used for applications requiring very high strength and low weight is the use of carbon fiber.

Fiber formation

Glass fiber is formed when thin strands of silica-based or other formulation glass is extruded into many fibers with small diameters suitable for textile processing. The technique of heating and drawing glass into fine fibers has been known for millennia; however, the use of these fibers for textile applications is more recent..

 

Properties

Glass fibers are useful because of their high ratio of surface area to weight. However, the increased surface area makes them much more susceptible to chemical attack. By trapping air within them, blocks of glass fiber make good thermal insulation, with a thermal conductivity of the order of 0.05 The strength of glass is usually tested and reported for "virgin" or pristine fibers—those which have just been manufactured. The freshest, thinnest fibers are the strongest because the thinner fibers are more ductile. The more the surface is scratched, the less the resulting tenacity.

Gelcoat is a material used to provide a high quality finish on the visible surface of a fibre-reinforced composite material. The most common gelcoats are based on epoxy or unsaturated polyester resin chemistry. Gelcoats are modified resins which are applied to moulds in the liquid state. They are cured to form crosslinked polymers and are subsequently backed up with composite polymer matrices, often mixtures of polyester resin and fiberglass or epoxy resin with glass, kevlar and/or carbon fibres.

The manufactured component, when sufficiently cured and removed from the mould, presents the gelcoated surface. This is usually pigmented to provide a coloured, glossy surface which improves the aesthetic appearance of the article, such as a counter made with cultured marble.

Many marine craft are manufactured using composite materials. The outer layer is often a gelcoat, typically 0.5mm - 0.8mm in thickness. Gelcoats are designed to be durable, providing resistance to ultraviolet degradation and hydrolysis. The gelcoat will often carry a pigment that provides the finish colour to the moulded item. Specialised gelcoats can be used to manufacture the moulds which in turn are used to manufacture components. These require very high levels of durability to overcome the mechanical and thermal stresses encountered during the curing and demoulding processes.

 

 

 

 

 

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