Plastics Plastics and and

Synthetic FibresSynthetic Fibres

Topic 13

Synthetic Fibres• Many items of clothing contain

materials such as polyester, polyamide, terylene, rayon, dralon etc.

• The items previously mentioned are all man-made fibres, and are called synthetic fibres.

Origin of Plastics

• Crude oil is used to make plastics and synthetic fibres.

• Long chain hydrocarbons can be cracked or broken into a mixture of short chain hydrocarbons, some of which are saturated and others unsaturated.

Properties of Plastics

Plastics Uses Properties

Poly(ethene)

Plastic bags Strong, light, waterproof

Polyamide Blouses, tights Hard wearing

Polyester Shirts, blouses, quiltsWears well, helps keep shape of clothing, warm

BakelitePot handles, electrical sockets

Does not melt or conduct heat or electricity

Rubber Soles of shoes, tyres Flexible, waterproof

Dralon Furniture coversHard wearing, stain resistant

Uses of Natural and synthetic fibres

FibreFibre Natural / Man-madeNatural / Man-made OriginOrigin

Cotton Natural Cotton plant

Polyamide Synthetic Crude oil

Polyester Synthetic Crude oil

Silk Natural Silk worm

Viscose SyntheticCotton plant after

treatment

Wool Natural Sheep

Advantages and disadvantages of plastics

Plastic Advantages Disadvantages

Poly(ethene) Cheap, waterproofDoes not rot away

Melamine/FormicaHeat resistantNot as attractive as wood

Polyurethane foam

Makes cheap seating

Gives toxic fumes when burned

PolystyreneMakes protective TV cases

Made from crude oil which is a finite resource

Silk (Natural) More attractive More expensive

• Natural fibres such as silk, cotton, wood and paper are more likely to be BIODEGRADABLE (will break down naturally)