PLASTICS

- Plastics consist of long chains of atoms which are mostly composed of carbon.

- Plastics can be classified into natural and synthetic plastics.

- The process of manufacturing plastic is called polymerisation.

- Plastic materials are resistant, insultating, ductile, malleable, impermeable and light.

- There are three types of plastic recycling processes: chemical and mechanical recycling and energy recovery.

- Thermoplastics are usually made from petroleum products. The most common thermoplastics are:
· Polyethylene terephthalate (PET)
· High-density polyethylene
· Polyvinyl chloride (PVC)
· Low-density polyethylene
· Polypropylene
· Moulded polystyrene
· Expanded polystyrene or Styrofoam

- Thermosetting plastics are made from petroleum products. They include:
· Polyurethane
· Bakelite
· Polyester resins

- Typical elastomers include rubber and neoprene

- Various industrial techniques can be manufacture plastic products, such as: extrusion, calendering, vacuum forming and moulding.

- The main techniques for using moulds are as follows: blow moulding, injection moulding and compression moulding.

- Modification techniques use tools and machines to make changes to prefabricated materials, such as sheets, bars or muldings.

- Examples of these techniques include: measuring, drawing marks and lines, cutting, drilling, filing and sanding and joining.

- You must always pay special attention to health and safety rules.

- Both natural and synthetic fibres can be woven to make a variety of textiles.

- Natural fibres may come from animal sources (wool, silk), plant sources (cotton, linen, esparto, bamboo) and mineral sources (gold, silver and copper fibres).

- Synthetic fibres, such as nylon, polyester, rayon and Lycra, are plastic materials.