This type of plastic is used for strength, impact resistance, clarity and barrier resistance to things such as moisture, oxygen and many chemicals. PETE is typically produced in clear, but can also be done in colors such as green and amber.
HIGH DENSITY POLYETHYLENE
The natural state of HDPE is a cloudy, slightly translucent color. It has good chemical resistance, does not absorb moisture and provides a good water vapor barrier. HDPE is one of the most popular plastics for molding bottles and containers.
Typically clear in appearance when used for containers, PVC has outstanding resistance to water, alcohols, concentrated acids and alkalines. PVC can be produced to yield superior flexibility.
LOW DENSITY POLYETHYLENE
Translucent in color with a tough, waxy texture, LDPE is a very flexible plastic with good barrier properties.
It is best known for flexibility and versatility. It can be molded into many applications, the most popular use in packaging is for closures. PP is very tough and has good chemical resistance. Although normally translucent in appearance, PP can be made a variety of colors.
A very clear, rigid plastic. PS has good chemical resistance, but no moisture or oxygen barrier properties. PS tends to be brittle, so cracks and breaks easily.
Can be any combination of plastics. Usually one of the above plastics mixed with an additive or barrier plastic to enhance the properties of the final container.