(1) Synthetic polymers such as polyethylene and polypropylene are produced by free radical addition reactions.(2) high-impact polypropylene(3) Woven and nonwoven geotextiles, usually made from polyester and polypropylene , are two types of geosynthetics.(4) polypropylene underwear(5) Polyethylene, polypropylene , polystyrene, silicone, and rubber are among the materials that are not responsive to the process.(6) Examples of linear polymers include polyethylene, polyvinyl chloride and polypropylene .(7) Taking along some extra clothing like lightweight polypropylene underwear and a balaclava in your cave pack can make your trip more comfortable and might be a life saver.(8) Wear a wicking material like polypropylene against your body to keep your skin dry, and top it with a waterproof jacket that's also wind resistant.