Plastics Lumber

As a stmctural element to support paneling and wall mounts, there is growing iaterest ia the use of plastic lumber produced usiag the recycled scrap or waste of polyethyleae (HDPE), polypropyleae, and PET materials from various packagiag and other high turnover appHcations (12,17,18,21,23,24,32,34,44,62,68-71). 

One outlet for polypropylene, polyethylene, and polyvinyl chloride waste is plastic lumber. These materials, often containing more than one polymer and a wide variety of additives, provide superior weather resistance in humid environments when compared to natural wood. To manufacture these materials, the compound incorporates compatibilizers, which allow dissimilar polymers to mix evenly, Additionally, they assist in the incorporation of fillers and additives, such as wood flour, calcium carbonate, and pigments. 

Plastic lumber can be manufactured from mixed-polymer post-consumer recycled materials. One example incorporates polyethylene and polypropylene into a final material. How do processors achieve this incorporation in light of the immiscibility of the two polymers ... 

CPRR, another pilot plant with an ET/1 extruder has been installed to make plastic lumber out of mixed plastics. Lower-melting plastics in the mixture act as a matrix that carries other plastics, and even up to 40%... 

Profiles, was recently opened to make plastic lumber profiles using a proprietary, continuous-extrusion process developed in-house. 

Another type of plastic recycling doesn t involve a phase change at all. Instead, plastics are chopped into small pieces and pasted back together in new forms. Such plastic lumber can be used to construct park benches, porches, and playground equipment. 

Mixed waste paper can also be utilized for uses other than paper. The uses include (1) molding of paper fibers mixed with PE or polypropylene to form door panels, trunk liners, and plastic lumber (2) nonwoven mats of up to 90% paper fibers held together by synthetic fibers and (3) composites of wood, paper fiber, and gypsum. 

Plastic lumber is made from recycled plastic, especially soft drink bottles and polyethylene waste. 

Some of the procedures of value for processing of mixed plastic wastes may also be useful for the recovery of value from the laminates used for efficient packaging of food and beverages (e.g., milk cartons, Tetrapaks). A combination of heat and pressure may be employed on a recycle stream of this type of material to fuse the mixed fibrous and resin components into a dense board-like product [31, 32]. This highly weather and insect resistant product, Eco Superwood Plastic Lumber, may be sawn, nailed, drilled, etc., like wood, and it resists rotting in direct contact with the soil without the need for preservatives. 

B.A. Hegberg, Technologies for Recycling Postconsumer Mixed Plastics Emerging Plastic Lumber Production, Office of the Univ. of Illinois Center for Solid Waste Management and... 

Lem, K.W. Letton, A. Izod, T.P.J. Lupton, F.S. Bedwell, W.B. Composition Containing Caprolactam-Free Residue from Depolymerization of Nylon 6 Carpet and Use Thereof in Paving Asphalt, Plastic Lumber and Crack Sealants. US Patent 6,214,908, April, 10, 2001, USP 6,414,066, July 2, 2002. 

Residential carpets are continuing to be more visible in MSW. Carpets are quite complex with polyamide/PP/PET face libers, PP backing, latex adhesive, and calcium carbonate as tiller. In addition, the recycled carpet will have a higher amount of dust particles. There have been efforts in the United States to collect residential carpet. As it is very difficult to separate the different components of the carpet, the reasonable way is to shred the carpets and pelletize it so that the pellets can be used in products such as plastic lumber. Only a small percentage of the face materials (nylonb and nylon 66) are recovered and recycled. 

The extension of life for a polymer in a "down-graded" application may tolerate a wide range of mixtures. "Plastic lumber" can be made from various mixtures where the application (thick-walled containers, park benches) can compensate for low... 

This book summarizes information on plastics recycling based on studies conducted for the state of Illinois. Part I discusses characterization, collection, costs, and markets for mixed plastics recycling. Part li discusses recycling technologies, Including those for processing and separation, buyer specifications, and the manufacture of plastic lumber. Appendices Include lists of scrap plastic handlers and brokers, manufacturers of recycling equipment, and information sources. 

Note According to The Freedonia Group, composite and plastic lumber decking demand in 1999, 2004, and 2009 (forecast) was/will be (in million) 317, 662, and 1,370, respectively. According to Principia Partners, only composite decking was sold in North America in 2004 for 670 million. 

CompositeA Plastic Lumber, The Freedonia Group, Cleveland, OH, 2006. 

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