Polylactide fibers (PLA), textured by false twist at different temperatures (135, 150 and 165º C) and draw ratios (1.30, 1.35 and 1.40) were stabilized by the application of a continuous thermal treatment at 100º C and 50 m/min. The effect of thermal stabilization on the microstructure was determined by physicochemical tests such as iodine sorption or differential solubility. Iodine sorption and differential solubility are closely related to the crystallinity of the samples. Stabilization enhances crystallinity and orientation with the result that differences between the samples are diminished. Color value differences, albeit reduced, in some cases exceed the accepted limits. Color absorption is mainly dependent on the orientation and accessibility of the amorphous phase
Naik, A.; Montero, L.; Riva, A.; Prieto, R.; Riba, M.; Vidal, E.; Cayuela, D. International Textile, Clothing & Design Conference p. 142-145 Presentation's date: 2010-10 Presentation of work at congresses
Electronic version of an article published as "Enzyme and microbial technology", 08 Desembre 2009, p. 1-5
Wool fibres have been modified with nordihydroguaiaretic acid (NDGA) to improve their performance at use. This water insoluble bi-functional phenolic compound has been grafted on wool through a laccase enzyme catalyzed reaction in an aqueous-ethanol mixture. The capacity of laccase to oxidise NDGA in this aqueous-organic medium has been studied electrochemicaly. The increase of CH2, CH3 and aromatic groups signal in the DRIFT spectra, together with SEM images of the enzymatically-modified fabrics confirmed the covalent grafting of NDGA on wool. This one step enzymatic process for grafting of NDGA improved the physical and mechanical properties of wool fabrics such as shrink resistance, crease recovery and tensile strength. Furthermore, the NDGA imparted to the textile material strong antioxidant activity and UV-protection.