How long is a piece of plastic string? ‘That may depend on the length of polymer chain it was made from’.
Plastic is one of mankind’s most useful and life-saving inventions. There are very few products that have contributed to the development of the modern world as much as plastic polymers. From containers for safe drinking water, insulating copper electrical cables in our buildings, phones, household goods, thermal insulation, bearings, sheeting, netting, medical, windows and plumbing just to mention a few. The list of the uses for plastics polymers are diverse and numerous.
The first plastics were invented over 100 years ago. The first plastic made from synthetic compounds was polyoxybenzylmethylenglycolanhydride, unsurprisingly, became commonly known as ‘Bakelite’ after the Belgian-born chemist Leo Baekeland. It is a thermosetting phenol formaldehyde resin. Thermoset resins are used today in Epoxy resins (glues, fibreglass) Polyester Resin Melamine (worktops) & urea formaldehyde (particle board/low-density fibreboard).
Another early plastic is cellulose acetate which is an organic plastic made from cotton or wood pulp first made in 1865. It is still in use today for camera film eyeglasses frames and laminating film and can be mixed with natural fibres to make a fabric.
Virtually all thermo polymers can be recycled:
a) back into the original product, or
b) into a lower specification product.
Manufacturers have difficulty in persuading buyers that some products could be made from reprocessed materials; although there appears to be a growing trend towards using part recycled materials. Some materials, especially engineering plastics, are more suitable for injection moulding rather than used in an extrusion process
In the next blog we will discuss the various use of the main polymers. It is very important that the correct polymer is used for any application. We would strongly advise any designer to ask advice on which type of plastic should be used from the manufacturers of the material or product.