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Greener Solutions 2017

Mushrooms and Silver Ragwort Leaves

Ten students in two interdisciplinary teams investigated alternatives to perfluorinated compounds for DWR (durable water repellancy) in outdoor clothing (WLGore), and increasing strength, flexibility and durability in mycelium-based leather (MycoWorks). They presented their findings to partners and a public audience of approximately 35 people on December 6, 2017.

Many of their ideas came from nature, such as the hydrophobic and self-cleaning characteristics of the lotus leaf. While neither team ultimately used the lotus leaf as a model for performance, other nature-based strategies were also investigated and then translated to the molecular scale.

The Gore team was challenged to create a high-performance fabric treatment that could resist both water and oils. They recommended silica nanosols and blow spinning as the two most promising solutions; these reported the best hydrophobicity, potential for oleophobicity, and application to textiles.

A silica nanosol coating provides hierarchical structuring through silica nanoparticles that bond with the surface of a synthetic fabric (e.g. polyester). Silica nanosols are highly hydrophobic but not as oleophobic as desired. The team suggested adding a liquid-like coating such as dimethyldimethoxysilane to the silica solution to improve oleophobicity.

Blow spinning is a process to create textured, microfiber mats which are hydro- and oleophobic, similar to the Silver Ragwort leaf. Blow spinning seemed less hazardous than other processes (such as electrospinning) since the process uses a non-toxic compressed gas (i.e. air or argon) and can use ethanol or propanol as a solvent for a variety of synthetic polymers that then form the fibers. The team recommended that Gore use blow spinning to create microfiber mats to coat their clothing textiles.

Here is their full report:

Gore Final Report 

Gore Final Presentation Slides

The MycoWorks team also worked in the apparel space as they were challenged with improving performance in a product that was already more sustainable than traditional leather making and included no toxic materials in either the finished product or manufacturing process. Their main concern was in producing a supple mushroom-based “leather” that held up to mechanical stresses and environmental moisture.

They proposed three methods to increase the strength and flexibility of the product by cross-linking chitosan in the material, using genipin among other materials, and applying a moisture barrier of corn zein to prevent leaching of the plasticizer.

Here is their full report:

MycoWorks Final Report

MycoWorks Final Presentation Slides




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