Meeting the Challenge of Thermoset Recycling for Under-the-Hood Applications

The composites industry has made considerable progress toward the recycling of sheet molding compound (SMC) and bulk molding compound (BMC). Composite recyclate generated from the grinding of thermoset parts is being used commercially in several “primary” applications; that is, in applications where performance requirements are comparable to those of applications which use virgin product. In order to increase the utilization of composite recyclate, the industry must overcome the paradox that recyclate-containing SMC is cost effective relative to alternative recyclable materials but is more expensive than virgin SMC. It is also desirable to develop formulations which utilize greater proportions of recyclate and which perform in the full range of applications which presently use SMC.

Although the utilization of post-consumer scrap for recyclate appears to be technically feasible, the lack of an infrastructure to economically recover the scrap presents a challenge. As the industry addresses that challenge, the opportunity to incorporate non-SMC post-consumer wastes as inputs to SMC and BMC may be an effective approach to achieve substantial post-consumer content in current products. Utilization of currently extractable post-consumer wastes for incorporation into composites may be the most effective short term means for our society to integrate its waste management needs and should not be overlooked in the quest for environmentally-friendly materials.