Fibroin Grafting Onto Wool Fibers: Recent Advances and Applications

Abstract High amounts of short fiber by-products not suitable for spinning are produced from silk manufacturing. These high protein content materials (about 94% wt) are suitable as a source of purified fibroin for biopolymer applications. An application not yet thoroughly studied is the use of fibroin solutions as a functional textile auxiliary for permanent finishing of wool garments. The aim of this work was to obtain sheath/core bicomponent fibers by coating wool fibers with thin films of silk fibroin. A polyfunctional chemical to graft fibroin onto the wool fiber surfaces without damaging the physical and chemical properties was searched to obtain wash-resistant finishing. Bifunctional as well as trifunctional epoxides were investigated. The finishing of wool with fibroin confers to the fabric innovative shine and handfeel effects, associated with an improvement of shrink resistance (antifelting) properties. The best operating conditions to obtain wool fabrics with homogeneous fibroin coating were determined.