Flexible packaging (specifically plastic bags) are generically referred to as “Poly” products. They are manufactured from petroleum-derived resins known as thermoplastic polymers that have the capability of being shaped through the application of heat and pressure into plastic sheets. These sheets are then converted to various bag configurations.
The majority of poly bags are constructed from polyethylene and polypropylene thermoplastics. Polypropylene polymers produce a rigid clear plastic bag with exceptional clarity and high resistance to water, acid, and salt. Polyethylene polymers produce a tough, flexible plastic bag, which can be used a large variety of applications ranging from food to industrial uses.