The most popular type of thermoplastic used in the plastic bag industry is called polypropylene. This type of plastic is non-toxic, sturdy, flexible, and lightweight—making it perfect for poly bags. The diversity in poly bags makes them an option for many industries and applications. They can be standard sized or custom made with different strengths, colors, sizes, shapes, and prints.
In manufacturing industries, such as automotive or aerospace parts production, polypropylene bags can be used to store small parts. Housing these small parts in poly bags is done to protect them from environmental hazards such as dust and chemicals. Some of these parts can also be larger which may need a heavy plastic for strength and durability. Another major example is polypropylene bags used in the food and beverage industry, where strict FDA regulations require the use of non-toxic bags so that the food is not altered by chemicals seeping in from the plastic.
Another popular type of poly bag is the re-closeable zip bag. These types of bags can be used at home for lunches or for museum and archival storage, depending on the type of protection needed. Drawstrings may be attached for plastic shopping bags in commercial settings, and printed plastic bags are often made of polypropylene as well.
Every process that polypropylene goes through to become a plastic bag begins with melting down the polypropylene resins until it is a thick liquid that is then extruded through a die where air pressure is applied to make the plastic bubble-like. The plastic is then stretched out into a thin film where the thickness is carefully controlled. In the final stages, winding, casting, or sheet extrusion techniques can be used before cutting the plastic to form individual bags.
Polypropylene Bags
The most popular type of thermoplastic used in the plastic bag industry is called polypropylene. This type of plastic is non-toxic, sturdy, flexible, and lightweight—making it perfect for poly bags. The diversity in poly bags makes them an option for many industries and applications. They can be standard sized or custom made with different strengths, colors, sizes, shapes, and prints.
In manufacturing industries, such as automotive or aerospace parts production, polypropylene bags can be used to store small parts. Housing these small parts in poly bags is done to protect them from environmental hazards such as dust and chemicals. Some of these parts can also be larger which may need a heavy plastic for strength and durability. Another major example is polypropylene bags used in the food and beverage industry, where strict FDA regulations require the use of non-toxic bags so that the food is not altered by chemicals seeping in from the plastic.
Another popular type of poly bag is the re-closeable zip bag. These types of bags can be used at home for lunches or for museum and archival storage, depending on the type of protection needed. Drawstrings may be attached for plastic shopping bags in commercial settings, and printed plastic bags are often made of polypropylene as well.
Every process that polypropylene goes through to become a plastic bag begins with melting down the polypropylene resins until it is a thick liquid that is then extruded through a die where air pressure is applied to make the plastic bubble-like. The plastic is then stretched out into a thin film where the thickness is carefully controlled. In the final stages, winding, casting, or sheet extrusion techniques can be used before cutting the plastic to form individual bags.