Mycelium-Cellulose Integration Yields Water-Resistant Textiles with Sixfold Strength Increase
- Gauri Khanna
- 56 minutes ago
- 3 min read
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Researchers at Purdue University engineered textiles combining Ganoderma sessile mycelium with cellulose fibres, achieving water contact angles up to 139° and tensile strength increases of 6× in nonwoven materials and 56% in woven cotton
The semi-interpenetrating network leverages hydrophobins on aerial mycelium for water resistance whilst maintaining breathability at 48 mL cm⁻² s⁻¹ air flow rate and 94% water vapour transmission
Life cycle assessment demonstrates 54% lower ecosystem impact, 62% lower human health impact, and 71% lower resource depletion compared to polyester textiles
The textile industry's dependence on petroleum-based synthetic fibres, comprising roughly two-thirds of the global market valued over $2 trillion, presents persistent sustainability challenges. While cellulose represents the most abundant biopolymer and offers renewable alternatives, its inherent hydrophilic nature limits its applications that require moisture resistance. Research published in Advanced Functional Materials demonstrates a biomaterials approach that addresses this limitation through the integration of mycelium.
Interface Engineering for Functional Properties
Scientists at Purdue University developed bio-textiles by cultivating Ganoderma sessile mycelium within cellulose fibre scaffolds, creating what they term mycelium-cellulose fibre (MCF) networks. The process exploits cellulose's hydrophilic properties and porous structure as a microfluidic substrate supporting mycelial colonisation. Cellulose fibres, soaked in nutrient solution containing glucose and corn steep solids, were inoculated with fungal cultures and incubated at 28°C for one to four weeks.
The resulting semi-interpenetrating network exhibits mycelial hyphae, ranging from 0.3 to 3.6 micrometres in diameter, infiltrating and adhering to cellulose fibres approximately 10 micrometres in diameter. Scanning electron microscopy revealed numerous smaller hyphal filaments connecting to larger cellulose fibres, forming junctions through physical entanglement and hydrogen bonding mediated by extracellular polymeric substances, including glucan and chitin on mycelial surfaces.
Critically, the mycelium adheres through surface interactions rather than invasive penetration into fibre cores, preserving cellulose structural integrity. Cross-sectional imaging confirmed uniform mycelial distribution throughout materials, with hyphae binding cellulose fibres in multiple planes and increasing network density.
Water Resistance and Mechanical Enhancement
The technology's functional advantages derive from the properties of aerial mycelium. These structures express hydrophobins, self-assembled proteins that impart hydrophobic characteristics. After three weeks' incubation, MCF nonwoven textiles achieved water contact angles of 139°, attributed to synergistic effects between increased surface roughness and hydrophobin presence.
According to the Cassie-Baxter model, air pockets form between hydrophobic mycelial surfaces and incoming water droplets, preventing penetration. Calculated hydrostatic pressure peaked at 209 kilopascals after three weeks, indicating maximum water resistance. Despite network densification, materials maintained breathability with sufficient air flow rates of and water vapour transmission rates, amounting to up to 94% of original nonwoven textile values.
Mechanical properties improved substantially through interface formation. MCF nonwoven textiles demonstrated tensile strength increasing from 0.7 to 4.0 megapascals after two weeks, a sixfold enhancement. This improvement exceeds what network densification alone could achieve, as density measurements showed only twofold increases. The researchers attribute mechanical gains to multiple mechanisms: physical entanglement between cellulose and mycelium, adhesive effects reinforcing the matrix, and interfacial hydrogen bonding.
The methodology proved adaptable across natural fibres. Mycelium integration with cotton, jute, and flax yielded tensile strength enhancements of 56%, 22%, and 38% respectively, with final strengths ranging from approximately 20 megapascals (cotton) to 570 megapascals (flax).
Durability and Environmental Performance
Durability testing demonstrated practical viability. MCF textiles retained 88% of original tensile strength and 90% of water resistance after 50 washing cycles. Following 100 abrasion cycles, materials maintained tensile strength at 2.5 megapascals, exceeding original cotton fabric values, with water contact angles of 129°. Environmental aging tests (acid rain exposure, humidity, temperature) reduced tensile strength minimally, with materials retaining over 85% of original strength and water contact angles above 125° in most conditions.
Life cycle assessment using 'Eco-indicator 99' methodology revealed substantial environmental advantages over polyester textiles: 54% lower ecosystem impact, 62% lower human health impact, and 71% lower resource depletion. Carbon emissions (approximately 2.4 kg CO₂ per kilogram) and energy consumption (25.9 megajoules per kilogram) were significantly lower than polyester equivalents (6.2 kg CO₂ per kilogram and 104.6 megajoules per kilogram respectively).
The research demonstrates scalability through uniform 20 cm × 20 cm prototypes, suggesting potential for commercial textile manufacturing whilst offering biodegradable alternatives to petroleum-derived materials dominating current markets.