New man-made fibres under the microscope - Lyocell fibres and Nylon 6 block co-polymers

Two new synthetic fibre types are now being produced and marketed commercially. The first type is known collectively as Lyocell fibres, a new generic name given to solvent spun cellulosic fibres which are produced by the NMMO (Amine oxide N-methylmorpholinoxide) process. The second type, a Nylon 6-based block co-polymer, is designated as a polyoxyamide fibre. Samples of both types were examined to determine how they might be characterized. The Lyocell fibre ''Tencel'' (Courtaulds, UK) and ''Lenzing Lyocell'' (Lenzing AG) were found to be very similar to high wet modulus viscose, but could be distinguished from viscose and modal fibres by a careful examination of their morphology and by accurate birefringence measurements. ''Vivrelle'' (Snia, Italy) and ''Hydrofil'' (Allied Signal Inc., USA) very closely resembled Nylon 6, but had differences in their infrared spectra.