These naturally white continuous filaments are almost as strong as nylon, and equally resistant to the effects of chemicals and marine organisms. With the best abrasion resistance of any fiber, filament polyester fibers stay strong wet or dry and remain flexible in all kinds of weather. Ropes constructed from polyester resist internal wearing and UV degradation. In contrast to nylon, polyester has relatively little tendency to stretch. Low elongation in relation to high strength afford superiority where strength, abrasion resistance, and low stretch are required.
Polyester has excellent repeat loading ability and continuous flexible, easy handling.
Wet or dry, the strength is virtually the same. It is so light it floats, and is unaffected by water, as well as resistant to most common industrial solvents and chemicals. Naturally clear, but extremely receptive to color at the time of extrusion, polypropylene consists of long molecular chains made by rearranging the chemical structure of simpler compounds derived from petroleum or natural gas. If unstabilized, it is easily destroyed by combinations of light, moderate heat, and oxygen. With the help of stabilizer systems and light protective pigments, polypropylene ropes can be made resistant to sunlight, though this quality varies greatly among manufacturers.