Common Codes of Plastic
Codes of Plastics - Part One
1. PETE or PET (polyethylene terephthalate)
This code is a common code in transparent pet bottle like mineral water bottles, and other drink bottles. Plastic with this code has a good barrier against oxygen and carbon dioxide. So, many bottles use this kind of plastic, especially soft drinks. Bottle with this code may only used once. You can’t add new water when it’s empty or even add hot water. It can cause the polymer layer in the bottle to melt and produce carcinogenic materials that can trigger the growth of cancer. Nevertheless, this kind of bottle is also hard to clean and can trap bacteria, causing many kinds of stomach illness.
2. HDPE (high density polyethylene)
This one used to be milk jugs, water gallons, chairs, chemical bottles, toys, etc. On food containers, this bottle also can only used once. This plastic is much stronger than PETE or LDPE, lighter, and much cheaper than the other plastic. This plastic can be recycled by remolding, although the quality of the plastic will not as good as new.
3. V or PVC (polyvinyl chloride)
This is the hardest plastic to recycle, for example, plastic wrapper, and many kinds of bottle. This kind of plastic can melt and contaminate food in -15°C (59°F). It can cause liver and kidney damage. PVC is resistant to acids and bases. PVC is also a good barrier against weather. That’s why PVC usually used for water pipes, canoe, garden hoses, roofs, electric wires, etc.
4. LDPE (low density polythylene)
This plastic usually used for foods, wrapping foil, etc., and this kind of plastic usually flexible and easy to bend. Plastic wrapper for food or bottle with this code is safe enough for usage. But unfortunately, this plastic is barely can be destroyed. This plastic can only be recycled by remolding, same as HDPE. LDPE has a good resistance to water, moisture, and most organic solvents or chemical, except with strong aromatic.
Codes of Plastics - Part Two
5. PP (Polypropylene)
Plastic container with this code is the safest and good for foods and drinks. This plastic used for food plate and bottles for baby, and also suitcase, children`s toy bin, etc. The plastic surface is soft, and easy to scratch. Usually, the plastic is transparent. Try to use plastics with this code for food and drink.
6. PS (polystyrene)
This kind of plastic is not weather resistant, so it’s not suitable for outdoor uses. PS burns easily, but slowly. PS is resistance to water, acids, bases, and detergents, but not in almost all solvents.
For example, Styrofoam, used to be disposable drinking glass or food plate. This material can contaminate with food when the container filled with food. This styrene material could be dangerous for brain and nerve system.
Codes of Plastics - Other
This code usually divided by 4, which will be explained later in the end. This plastic used to be foods or drinks container, home appliances, computers, and other. Plastic with 7 SAN and ABS code are safe for foods or drinks. But, for PC code, better not for foods or drinks, because can produce dangerous chemical compounds.
a. SAN (styrene acrylonitrile)
SAN plastic is similar to ABS and PC, but this plastic is much more resistant to chemical solution and hot water.
b. ABS (acrylonitrile butadiene styrene)
This plastic has average strength and price, glossy, and suitable for outdoor appliances. Usually, this plastic used for LEGO building bricks, computer mouse, vacuum jug, etc. Resistant to some bases but not to other solvents than alcohol.
c. PC (polycarbonate)
PC is a very thick and strong plastic. It is very difficult to break. This plastic used for mixture in bullet-proof glass, and water container. PC is resistant to oils, fats, alcohols, and high temperatures. But hot water reduces its ductility.
d. Nylon
Nylon has good strength, lustrous, and usually for seat belts, tire cords, and other uses. Nylon is resistant to chemical solution. Nylon melts, instead of burning