The Steelcase team focused on one area of the current plastic manufacturing process that would require changes to execute polymer modularity — additives. The team chose the colorants used for the polypropylene Node chair line as the baseline for substitution and as a test for the concept of modularity. These colorants can be hazardous. For example, carbon black, a common colorant, is a well-known occupational hazard and probable carcinogen. The team was faced with two distinct but entwined parts of the challenge: finding more benign materials, like torrefied walnut shells for black, and better ways to affix the colorants. Rather than following the current methods of introducing separate colorants to a master batching process, however, they were on the hunt for how they could manipulate the polypropylene itself. They proposed grafting polypropylene, and using maleated polypropylene, and polypropylene binding peptides to achieve this. These strategies are a first step toward the concept of modular polymer manufacturing techniques, but understandably would require alterations to the current manufacturing and recycling processes and are therefore longer-term strategies.
