Fibers & textiles

Twenty-five subjects, from spider silk to diapers, that keep making the same point: performance lives in a structure, not in a material name. Leather works because of a three-dimensional collagen network, which milled plant biomass and fungal mats do not reproduce — so the coating and the backing carry the mechanics. Keratin must have its disulfide bridges destroyed to be extracted and then rebuilt from scratch. Dragline silk is a protein plus a spinning process, and the process is the hard half.

The second recurring idea: biology entered this industry through finishing, and cost per kilogram decides where it goes next. Enzymes clean hides but do not tan; the recycling enzyme cuts only amorphous polyester, so the problem becomes feeding it plastic in the right physical state; denim’s whole aesthetic rests on dye that never reaches the yarn core.

The third: fibre-to-fibre recycling is blocked by identification, not chemistry — by whether a machine can read a garment in a fraction of a second.

Start with biotechnology in textiles, which sets out that economics; the fibre, finishing and recycling pages then apply it.

Recombinant spider silk Spidroin architecture, the pH and shear gradient inside a spider's spinning duct, why repetitive genes are unstable in microbes, and why fibre-strength comparisons need reading with care.
Cork and mycelium in accessories Suberised closed-cell cork, chitin-glucan hyphal felts, and why bags and wallets made from them fail at the coating, the crease line and the stitch hole rather than in the biomaterial itself.
Bio-based baby diapers Why superabsorbent polymers swell, why cellulose-based cores lose capacity under load, why a hydrophilic topsheet is the wrong topsheet, and what actually causes nappy rash.
Bacterial cellulose sheet masks How Komagataeibacter spins cellulose ribbons at an air-liquid interface, why the resulting hydrogel conforms to skin, and the limits set by pore size, hornification and water activity.
Bio-based elastane in swimwear Hard and soft segments in segmented polyurethane-urea, why chlorine attacks the urea domains, why polyether soft segments photo-oxidise, and what a renewable-carbon claim does and does not change.
Biotechnology in textiles The cross-cutting constraint on biological routes into textiles: commodity fibre prices set a cost ceiling that fermentation must meet, which is why enzymes arrived first and grown materials remain at the premium end.
Cotton fibre grown in cell culture Fibre initiation, turgor-driven elongation, helical secondary wall deposition and the twist that makes cotton spinnable — and why detached cells in suspension produce cellulose without producing fibre.
Bio-based antimicrobial and odour finishes Why protonated chitosan disrupts bacterial envelopes, the enzymes that actually generate body odour, wash durability testing, and why a plant-derived active is still a biocide under EU law.
Algal pigments and living textile coatings Phycobiliproteins and why they photobleach, the difference between a pigment and a dye with fibre affinity, and the water and light budget that limits photosynthetic textile coatings.
Recombinant collagen in skincare The Gly-X-Y repeat, prolyl-4-hydroxylase and helix stability, why hosts must co-express the enzyme, and the difference between a topical film-former and an implanted structural protein.
Bio-based activewear Why moisture regain works against a cellulosic base layer, why the sonic behaviour of a knit is set by yarn geometry rather than fibre origin, and why elastane remains the unreplaced component of stretch garments.
Bio-based camouflage and armour materials The near-infrared red edge that a dyed fabric has to imitate, why sonic velocity and specific modulus decide ballistic performance, and where biological composites genuinely outperform: crack deflection rather than raw stopping power.
Bio-based footwear: mycelium, algae foam and pineapple leaf The chitin-glucan wall of a mycelium mat and why it needs a coating, why algae biomass is a filler in EVA rather than a foam polymer, and the binder problem in a pineapple-leaf nonwoven.
Bio-based underwear Why viscose and lyocell diverge sharply when wet, how skin bacteria convert odourless secretions into thioalcohols and branched acids, and why an antimicrobial finish is a regulated biocide rather than a fibre property.
Chitin and chitosan Why α- and β-chitin behave differently, what deacetylation actually changes, the pKa that governs chitosan solubility and its antimicrobial action, and why batch-to-batch variability limits regulated uses.
Enzymatic leather processing What shrinkage temperature measures, why bating and enzymatic unhairing act on non-collagenous proteins, why no enzyme forms the crosslink that tanning requires, and what the chrome alternatives cost in hydrothermal stability.
Industrial natural dyes Mordant coordination chemistry, why indigo is a vat dye that needs no mordant, how fastness is actually graded, and the land and variability constraints that keep plant colourants out of commodity dyeing.
Natural fibres and bio-textiles Microfibril angle and why flax is stiff and cotton is not, why bast fibres must be retted out of a pectin matrix, how staple length governs spinnability, and the variability that separates a fibre from an engineering material.
Recombinant collagen and gelatin The Gly-X-Y repeat and the triple helix, why 4-hydroxyproline is required for thermal stability, what prolyl-4-hydroxylase co-expression solves, and why Bloom strength does not follow automatically from a pure protein.
Bio-denim Ring dyeing with indigo, reduction to the leuco form, enzymatic and microbial routes to the dye, cellulase biostoning, and backstaining as its physical limit.
Antifungal socks The microclimate of the shod foot and the physiology of Trichophyton, wool's hygroscopicity and odour-acid binding, why regenerated cellulose inherits no bamboo chemistry, and how biocidal finishes are tested for durability.
Textile collection and sorting Near-infrared spectroscopy as the basis of automated textile sorting, why black fabrics and elastane blends defeat identification, and how the contamination threshold sets the boundary between fibre-to-fibre and downcycling.
Enzymatic textile recycling Cutinases and PET hydrolases, the role of glass transition and crystallinity, separating polycotton with cellulases, and the economic threshold set by the price of virgin terephthalic acid.
Keratin-based materials The disulfide network of keratin, reductive and oxidative extraction, the difference between the α-form in wool and the β-form in feather, re-crosslinking, and molecular-weight scatter as the governing limit.
Plant-based leather alternatives The collagen hierarchy and what tanning actually does, the substrate–polymer–filler construction behind plant alternatives, the tear and flex tests that separate them, and the legal protection of the word leather.