Abstract: Synthetic roofing products such as simulated slate and clay tile shingles, and other products, such as flower pots, floor coverings, plastic pallets and the like are compression molded from a mixture of ultra low density polyethylene binder and a filler which may comprise recycled rubber products such as E.D.P.M (ethylene propylene diene monomer) and S.B.R. (styrene butadiene rubber). Colorants may be added to the mixture prior to final molding. Many of the products, especially synthetic shingles, are less expensive, easier to handle, and more durable than the slate or clay tile shingle product simulated.

Abstract: An improved continuous crumbing machine for recycling rubber tires and other materials such as polyethylene containers, gypsum, hardboard, tin cans, glass jars and bottles. The device comprises a pair of rotating rolls having negative rake teeth of interlocking sprocket design formed on the outer periphery of each roll. The materials to be fragmented or crumbed are fed between pairs of rotating rollers having negative rake teeth. A plurality of stages of rotating rollers are placed in series to obtain the desired particle size.