STUDY UNIT 12: Mineral and inorganic fibres GLASS

Question 1

Glass

Answer 1

Glass is a manufactured fibre in which the primary fibre-forming substance is silica. It is produced in both filament and staple forms, and is also called fibre-glass. Glass fibres are made of silica, sand, soda ash, borax and limestone that are melted at 1650 oC and extruded through a spinneret. As the melted glass leaves the spinneret, it solidifies into fibres.

Question 2

Properties

Answer 2

Glass fibre is very strong. It has the tenacity of 56–61 cN/tex. It has virtually no elasticity and very little absorbency, and it will not burn. It has excellent resistance to age, sunlight, fungi and insects, but lacks abrasion resistance. Where a glass-fibre fabric repeatedly rubs against another surface such as a floor or window sill, it tends to crack.
Although glass fibres are non-allergenic, the cut ends of the fibres can be very irritating, causing a red rash similar to that of an allergic reaction.

Question 3

Care

Answer 3

Glass fibre fabrics should be laundered carefully, not dry-cleaned, and care taken to prevent excess abrasion. Never wring, spin-dry, iron or rub glass fibre fabrics. They should be washed separately, preferably not in a washing machine, as tiny fragments from the fibres may be left in the machine. Always wear gloves when working with glass fibre fabrics.

Question 4

End Uses

Answer 4

Glass fibre cannot be used in clothing, but can be used in curtaining, lampshade cloth, awnings and screens. It is mainly used in industry as insulating material, and also in filter cloth, fire blankets and the bodies of sports cars, dune buggies and boats.