The annual U.S. consumption volume of polypropylene is approximately 37 billion pounds and is second only to polyethylene.
Polypropylene comes in many different grades which offer a wide range of properties. Some general characteristics of PP include; good tensile and impact strength, high chemical resistance, relatively low cost, and versatility.
PP has a glass transition temperature of approximately -20 degrees Celsius, which makes it flexible at room temperature. It also has a relatively high melting point of approximately 165 degrees Celsius. PP is a semi-crystalline material that has a relatively high crystallinity of 50%-85%. This accounts for its translucency or hazy appearance in its natural form. The crystalline regions refract the transmission of light through the PP matrix and destroy clarity. Clarified grades of PP are available for applications that require excellent contact clarity.
PP is flexible and is easily processed. PP typically does not have great UV resistance, but a clear protective topcoat can be applied to packages made from PP. These combined properties make PP a viable and cost-effective material for high production volumes. PP is used in a wide variety of applications, including, but not limited to automotive, agriculture, medical / healthcare, packaging, fibers, building and construction, leisure / outdoors.