Biobased Poly(ester amide)s as Sustainable Coating Materials for Vegan Leather with Improved Haptic Sensation

Increased consumer awareness of animal welfare and environmental sustainability has driven the development of vegan leather alternatives to natural leather. Fossil-derived leather substitutes offer superior strength and thermal stability but often lack biodegradability, carbon neutrality and aesthetics. Biorenewable alternatives are more eco-friendly but typically suffer from insufficient thermal and mechanical properties and poor moisture resistance. This study presents the synthesis of mechanically reinforced, thermally enhanced and biodegradable poly(ester amide)s (PEAs) incorporating hydrogen bonds as vegan leather coating materials. Synthesized from biobased 1,4-butanediol, adipic acid and nylon 46 via a two-step transesterification/polycondensation process, the resulting PEAs exhibit over eight times higher tensile strength, 3-fold greater toughness, and enhanced thermal stability compared to their constituting homopolymers, poly(butylene adipate) and nylon 46. All PEAs disintegrate within 18 weeks and achieve over 60% biodegradation rate relative to cellulose under composting conditions within one month. When applied to mushroom fabrics, the PEA coating provides haptic sensations (slipperiness and softness) comparable to commercially available leather. Life-cycle assessment indicates that PEA-coated leather imposes considerably lower environmental impacts than both bovine and polyurethane-based leather. This novel material holds promise as a sustainable, high-performance vegan leather substitute.