Dyeing of N-modified viscose rayon fibres with acid and metal-complex dyes

Viscose rayon N -modified by the incorporation of polydiallyldimethyl ammonium chloride gave good dye exhaustion and colour yield on dyeing with acid or metal complex dyes. The amount of additive present in the fibre was assessed from its nitrogen content, and percentage exhaustion was found to increase with increasing quantity of additive. Changes in hue, in addition to an increase in the light fastness of deeper shades, are attributed to aggregation of dye within the fibre. The light fastness of metal complex dyes on N -modified fibre was very good but acid dyes gave poor results. Wash fastness was improved after treating with a dye fixing agent.     

Effect of molecular mobility on the deformation characteristics of polycaproamide fibres

The deformation characteristics of PCA fibres are a function of the deformation temperature to a significant degree. The character of the curves of E(ε), E_max(t), σ_b(t), and ε_b(t) indicate a pronounced change in the mechanical properties of PCA fibres not only in “thawing” of segmental mobility in amorphous regions of the polymer, but also in passage of crystallites into the mesomorphic state, which is characterized by pronounced weakening of interchain interactions in the crystallites. The first segment of σ(ε) is only observed in the curves for PCA fibres in the glassy state. In activation of segmental mobility, the σ(ε) curves only contain the second and third segments. St. Petersburg State University of Technology and Design. Translated fromKhimicheskie Volokna, No. 6, pp. 30–31, November–December, 1999.     

The fatigue properties of viscose rayon cord yarn containing structure-forming and thermo-oxidation inhibiting additives

Conclusions 1. It has been shown that it is desirable to combine a limited intensity of stretch-draw with a fairly prolonged exposure of the fibrous filament or thread in the hot-draw zone if increased modulus of elasticity is to be obtained.2. It has been made clear that the ratio of the intensities of plasticised to hot stretch-draw has little effect on the properties of polyvinyl alcohol fibre.3. It has been shown that the mechanical properties and the water resistance of stretch-drawn polyvinyl alcohol fibre is determined, in the first instance, by the intensity of hot draw, i.e., the orientation processes. The effect of the duration of the hot draw on these properties is manifested only over a limited interval of time, which may enable the orientation processes either to proceed or may worsen them.Leningrad Branch of the All-Union Scientific-Research Institute for Man-Made Fibre (VNIIV). Translated from Khimicheskie Volokna, No. 6, pp. 45–47, November–December, 1969.