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The suppliers of Sheet Molding Composite to the automotive industry recognize their responsibility to ensure that environmentally sound recycling techniques are in place for SMC as its use increases in automotive applications. To this end, automotive SMC molders and their material suppliers are investigating recycling processes which create the opportunity to produce viable products from recycled SMC. This paper will: introduce recycling processes available for SMC. describe the preparation of scrap SMC, from the point at which discarded vehicles and scrap SMC is collected, to the point at which SMC enters the recycling process. describe alternative recycling processes including pyrolysis and regrinding. describe the equipment necessary for recycling processes. discuss the characteristics and structural properties of the products from recycling processes and offer potential applications for those products.

The technology to recycle thermosets exists as reported in the bibliography. The purpose of this article is to explore the economics of recycling thermosetting sheet molding composite (SMC) wastes generated by the molding plants. The principles discussed here equally apply to other thermoset composites and, in general, to other plastics. A recycling model is presented that will accept waste SMC as input and delivers value-added end product for reuse as output. Recycling methods considered are briefly reviewed. A cost model is developed to illustrate the economics of various proposed recycling paths. SMC is assumed to be shredded at the molding sites and delivered to the “RECYCLING PLANT” (RP) in lieu of being shipped to a landfill site. A fee equal to landfill fees is charged for this service; a source of income for the RP.

A large variety of technological advances in materials, processing, equipment and design developed recently help further enhance the use of SMC automotive body panels. These developments include: 1. low profile, fast-cure and easy-flow SMC pastes; 2. fast-cure adhesives and bonding techniques; 3. in- mold coating, vacuum molding and paste degassing; 4. fast moving and "forced-parallelism" short stroke molding presses with precise controls on pressure, time and speed; 5. design optimization for molded parts, tooling and processing; 6. simultaneous engineering; and 7. continuous flow and information intensive manufacturing. These technologies help improve surface quality, lower manufacturing cost and reduce development time of SMC parts.