All of the case studies are presented to show that whatever the source of manufacturing scrap, it can be recycled and good properties are possible. The most unique case study, to me, deals with the machining residue of an E-glass/epoxy (70 wt. percent glass fiber) composite from Gordon Composite. Trim offs, reject parts and end-of-life components are obvious options for recycling, but machining and finishing scrap are not so obvious. This residue alone accounts for several million pounds of scrap waste per year at Gordon Composites and other fabricators. The study involved compounding 30 wt. percent of this residue with 5 wt. percent MAPP and 65 wt. percent PP using a Leistritz twin screw extruder to produce pellets that were then extrusion-compression molded into 6-inch by 6-inch plates. Flexure and tensile specimen were cut from these plates and tested in our facilities at UAB. Neat PP plates and test samples were also produced for comparison purposes. The flexural strength and modulus showed an increase of 20 percent and 30 percent respectively, while the tensile strength and modulus of elasticity showed an increase of 15 percent and 50 percent respectively.

You hope to one day see a composite recycling database where composite professionals can go to list their scrap or find scrap that they or another company can use in their own facility. How can other companies help make this a reality?

The answer is simple: help facilitate data. The work behind the answer, of course, is not so simple. From what I’ve experienced thus far, whether that be through research or interactions with companies through projects or conferences, there are three main things a company needs to focus on in order to help make the composite recycling database, and composite recycling in general, a reality. First, companies need to change their perception of scrap. Most companies call it “waste.” It cannot be thought of in that way. This material holds value. If it’s thought of as waste, then it will be treated as such. Most operators or handlers will let it fall to the floor, perhaps not worrying about stepping on it here and there, or even may throw it in with other types of “waste” that may ruin its integrity. Scrap needs to be thought of as a front-runner alongside raw materials when contemplating a new product. Utilizing scrap compared to virgin materials has its benefits even excluding costs. “Scrap” is definitely a better term than “waste.” Second, each company needs to take a stance on sustainability or even make it a priority and mandate it in their facility. Third, companies in our industry need to be educated about the types of scrap, the methods for preparing them for reuse (shredding, grinding, pyrolysis, solvolysis, etc.), and the various processing methods (compounding, extrusion-compression, etc.). This calls for companies to be willing to work with research facilities like the Materials Processing Applications Development (MPAD) Center here at UAB. These companies can provide a sampling of their scrap and at UAB we can do all the in between work including testing for mechanical properties. On a small scale, the MPAD can help companies work towards implementing a successful recycling program in their facility, all the while helping the recycling sector of the composite’s industry grow with their contribution to the database.

How do you think creating more sustainable composite products will advance the industry?

Creating more sustainable composite products will open up a secondary market in the industry where composite scrap that was previously being landfilled can now be stretched to a greater number of applications. Not to mention, the companies that participate will become more profitable by cutting out specific costs (landfill tipping fees, storage and transportation fees, legislative fees, etc.) and potentially bring in revenue from the secondary product. Reusing composite scrap will increase the market share in industries where sustainability/recyclability is mandated much like LEED building materials.

What other ways can the industry become involved in advancing sustainable composites options?

Companies collectively forming consortiums to provide resources towards research and development of common core problems that hold back the industry from recycling is key to advancing the growth of sustainable and recyclable composites. This is a new and upcoming sector in the composites industry where next generation engineers and researchers may hold the key to advancement and growth. Companies have the unique opportunity of working with university research facilities on a smaller and more intimate scale where their needs can be more properly addressed for the given project, as opposed to a bigger research facility. This requires company cooperation and student funding, but in the end, wouldn’t you rather spend your money to advance your company and the industry instead of sending it straight to the landfills?