Polypropylene is a synthetic fiber that is tough enough to use outdoors. These fibers are strong, and can withstand heavy foot traffic. They are also abrasion resistant, mildew resistant, UV-resistant, and quick-drying. Because it is solution-dyed, it is also the most colorfast of all fibers. These traits make many polypropylene rugs ideal for use where the sun and weather conditions may wear out rugs made of different materials. They often work well on a porch or poolside. These rugs can also be cleaned using strong cleaners without risk of damaging the fibers. Polypropylene rugs are machine-made, which reduces their cost significantly.
Polypropylene is widely used in the creation of toys, cars, rugs, food packaging, technology, and virtually everywhere plastic is found. Despite being used in industrial applications, it's actually soft to the touch - some have compared it to wool or other dense textiles.