Current State of Recycling Sheet Molding Compounds and Related Materials

Recycling of thermoset molding compounds has been intermittently investigated for roughly the past 15 years. The use of sheet molding and bulk molding compounds has steadily increased over the same time period, but no closed-loop recycling regime has been developed. First, a general discussion is made on the materials involved and some of their applications. The major recycling methodologies, energy recovery, chemical breakdown, thermal breakdown, and size reduction are all reviewed. Also, some of the new technologies being developed and areas where further work is needed are outlined.