Key Concepts: Plastics and textiles.

1. Plastic Materials.

• Plastics consist of long chains of atons which are mostly composed of carbon.

• Plasticscan be classifield into natural and synthetic plastics

• Plastic materials are resistant, insulation (against electricity, heat and sound) ductile, malleable, impermeable and ligth.

• There are three types of plastics recycling processes: chemical and mechanical recycling and energy recovery.

2. The Clasification of Plastics.

• Thermoplastics are usually made from petroleum products. The most common theroplastics are:

- Polyethylene terephalate (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

- Melanine

- Polyester resins

• Typical elastomers include rubber and neoprene

3. Plastics Forming Techniques.

• Various industrial techniques can be used to manufacture plastics products, such as: Extrusion, calendaring, vacuum forming and moulding.

• The main techniques for using moulds are as follows: blow, moulding and compresion moulding.

4. Modification Techniques.

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

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

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

5. Textiles

• Both natural and syntheetic fibres can be woven to make a variety of textiles

• Natural fibres may come from animal sources (wool, silk), plant sources (cotton, line, esparto, bamboo) and mineral sources (gold, silver, and copper fibre)