Mycelium was grown in a soft mold in the shape of a sole—“No waste
from cutting it into that shape,” said Cao—and the team settled on a
type of vegan “leather” to cover the sole and make it more durable.
Tang then designed and made the top of the shoe, using discarded
scraps from the muslin fabric that apparel design students use in the
clothing they create. She used a sewing technique called smocking, in
which she gathered the fabric to give it bulk and shape.
“I used vegetable dyes and 100
percent cotton thread,” Tang said. “The design looks like mushrooms look
when they’re stacked, and everything is completely biodegradable.”
More work remains on moving from a prototype to a potentially marketable shoe, but the team is optimistic.
With nearby Kennett Square, Pennsylvania, known as the Mushroom Capital of the World
and Delaware one of America’s top producers of broiler chickens, the
new composite has an ample supply of regional raw materials.
The researchers have partnered with Phillips Mushroom Farms in
Kennett Square and with Goodwill, which has a recycling center in New
Castle, Delaware. The feathers used so far came from a previous project
involving agricultural waste.
“The University of Delaware research combines the sustainability
strategies of local production and the use of bio-based renewable
resources to solve environmental problems related to the apparel and
footwear industries,” the EPA said in announcing the P3 grant award.
“This year’s P3 teams are applying their classroom learning to create valuable, cutting-edge technologies.”
Article by Ann Manser; photos by Wenbo Fan