James Drummond, who leads plastics engineering at Lexmark, has a very interesting and aggressive view about the future of post-consumer recycled (PCR) plastics. He is espousing—and implementing—a concept that Lexmark refers to as “the circular economy”.
“It is not hard to visualize a day where there will be demand for all used products to be broken down into each material type and have each material directed back into the supply chain. Whether this is a mechanical or chemical process is yet to be determined, but the advances seen in the last decade indicate a bright future for the reuse of all forms of plastic.”
Drummond made those comments in a paper presented last March to the Annual Technical Conference of the Society of Plastics Engineers (Antec). His paper reviewed how Lexmark revived its use of PCR starting about six years ago after the program had drifted when so much manufacturing moved to Asia.
In 2014, Lexmark recycled or reused more than 10,000 metric tons of plastic, metals and packaging. That’s up more than three-fold since 2004, according to the Lexmark 2014 Corporate Social Responsibility Report.
Lexmark’s most ambitious program is its cartridge collection program, in which it takes back its own cartridges and reuses some components and shreds others for use in its own captive compounding system.
In an interview, Drummond said that new cartridges can include up to 25 percent PCR content, but that number could grow. The primary materials used in new laser cartridges are high-impact polystyrene, ABS and polyacetal.
A much bigger challenge is boosting PCR content in printer hardware, where Lexmark buyers and engineers have had to identify third-party global suppliers. PCR materials represented 808 metric tons of the content of new printers in 2014 (about 10 percent). Lexmark’s latest laser printers are qualified to include as much as 40 percent PCR content.
Getting there is Drummond’s job and his Antec paper reads like a textbook on how to overcome all of the technical issues as well as resistance by third-party molders.
Here are a few highlights:
Bromine. Much older electronics waste from third parties contains bromine, which had been widely used as a flame retardant, but is now restricted. X-ray Florescence (XRF) can be used to keep out the brominated waste.
Polymer contamination. Fourier Transform Infrared Spectroscopy (FTIR) can be used to identify and help separate plastics that can contaminate the feedstock and weaken mechanical properties.
Aesthetics. Good cleaning and process control at the recycler is essential to avoid splay and inclusions that can affect part cosmetics.
Cost control. Customers want sustainability, but they don’t what to pay a premium for it. As a result, all of the engineering criteria must be achieved while also keeping costs below virgin materials, or at least neutral.
In one other interesting note, Lexmark has looked at bioplastics, but so far they aren’t a good fit. In some cases, their properties are not a match for the types of plastics Lexmark is using, such as ABS and HIPS. Also, the costs of bioplastics are often a significant premium above virgin and PCR materials.
Note: Antec papers are available to members of the Society of Plastics Engineers.