This Small Business Innovation Research Phase I project will develop an innovative, environmentally benign process for forming net shape products of superior quality and performance from dissimilar biomaterial components. Plastics and foams are dependent upon inherently unsustainable raw materials, require a high embodied energy to produce, and do not readily biodegrade at the end of their useful lives. This project will focus on the further development of an alternative material system: a self-assembling biocomposite which is literally grown in the dark using fungal tissue to bind heterogeneous particles of agricultural waste. The biodegradable material exhibits mechanical properties that rival synthetic foams and offers the potential to transform the multi-billion dollar protective packaging and structural cores industries. However, the thin-walled plastic forms used to shape resulting products during growth have a limited service life and must be replaced frequently. Removing or reducing dependence on these forms, through development of a gelatinizing growth substrate and process, will increase sustainability and yield, and reduce costs to further incentivize widespread adoption. The proposed research will answer questions that will determine whether this gel-assisted casting process is technically and commercially feasible, and therefore laying the groundwork for a Phase II project.
The broader impact/commercial potential of this project is difficult to overstate. Conventional methods of producing low-cost, high strength-to-weight ratio materials for protective packaging and building construction use up to 10% of the world's petroleum as feedstock and consume considerable energy in the production process. Mycological material technology eliminates the need for fossil fuel feedstock and currently requires only one-eighth of the energy to produce an equivalent volume as compared to synthetic foam. In addition, the products are non-toxic, fire-retardant, and readily biodegradable. The commercial potential is high, as products made of this material, as currently manufactured, already successfully compete in the marketplace with products made of expanded polystyrene and expanded polypropylene. The benefits to society at large include safer materials, the transition to regional manufacturing which will bolster local economies, the use of domestic byproducts as the primary raw material, lower energy consumption, and a production method which creates less waste and pollution. The successful completion of this project will help United States manufacturers to emerge as world leaders in the production and supply of sustainable materials, with the potential to serve numerous global markets.
. The existing process, MycoBond™, joins dissimilar materials using the growth of fungal tissue (basidiomycete mycelium) to bond heterogeneous particles (lignocellulosic agricultural waste) into a cohesive, uniform solid. The resulting product is a high performing, low cost alternative to synthetic foams ("Styrofoam", expanded polystyrene, expanded polypropylene) for protective packaging and construction materials. The existing MycoBondTM process relies on thin walled polyethylene (PE) tools (i.e., "forms") to hold the growing fungal mycelium in the net product shape during material incubation. The principal objective of this research was to reduce or eliminate reliance on this consumable plastic tooling, which accounts for approximately 40% of the total cost of goods sold (CoGS). A new fungal tissue cultivation method served as the preliminary adhesive for the process and permitted the substrate features to be retained during mycelium growth. The process tested four different particle and fiber sizes of raw material, three different angles of repose, three different inoculation methods, and 16 incubation conditions. The casted materials all had comparable growth rates to the controls grown in an enclosure, and offered increased compressive strength. The coarser particle sizes were unable to hold the feature resolution without significant draft angles, but finer particles and fibers retained dimensional stability. The second phase of this research will focus on process scaling, additional optimization of the incubation conditions, and obtaining better feature resolution.
