A series of novel monomeric dyes has been prepared by diazotization of 2-amino-3-carbethoxy-4, 5-dimethylthiophene and coupled with various N-arylmaleimides. The polymeric dyes were prepared by free radical polymerization of monomeric dyes. The resultant polymeric dyes were characterized by IR spectra, intrinsic viscosity, elemental analysis, number average molecular weight by VPO and thermogravimetry analysis. The monomeric dyes have been also characterized by elemental analysis and IR spectra. The purity of all the dyes were checked by thin layer chromatography and they have been applied on cellulose triacetate fibre as a disperse dye. Colour and dyeability of the polymeric dyes are discussed by comparing them with those of the corresponding monomeric dyes. The dyed fiber showed various colour shades with good to very good depth and levelness. The percentage dyebath exhaustion and fixation of the dyes on the fibre have been found to be good to very good. The light, washing, perspiration, sublimation and solvent fastness properties of the dyed fibre has been found to be very good to excellent.

View full abstract

It is well known that liquid ammonia is effective to improve the hand of cotton fabric and the treatment is carried out practically at present. In this study, we have done liquid ammonia treatment of regenerated cellulose fiber lyocell produced by the solvent spinning with N-methyl morphorine N-oxide. Change of the fiber structure by the treatment was investigated on the basis of the X-ray diffraction, dyeing properties, and KES shearing and bending hystereis characteristics. CelluloseII of the untreated lyocell was partially transformed to CelluloseIII_II by the treatment and crystallinity decreased only a little compared with the untreated. Apparent dyeing rate, diffusion coefficent and saturation dye uptake were decreased a little by the treatment, while hand of the fabric was changed a little to stiffer. From these results, the NH₃ treatment of lyocell was not effective for improvement of the hand in comparing with the cotton fabric. Furthermore, polynosic fabric was treated with NH₃ and the effect was investingated with X-ray diffraction and dyeing rate.

View full abstract

For recycling of textile wastes and for environmental preservation, preparation of carbonaceous adsorbent from cotton waste and its application to removal of endocrine-disrupting chemicals in water were investigated. In cotton towel carbonized at 600°C and activated at 850°C with steam, increasing activation time caused a decrease in microporous carbon yield and a linear increase in specific surface area. The specific surface area of microporous carbon with 50% yield was approximately 1000m²/g. Activation with air produced an equal yield of microporous carbon to steam activation, but a smaller mean pore diameter. The amount of 4-nonylphenol adsorbed onto both of the cotton waste-based microporous carbons was very high, even in extremely dilute solution, and efficient removal from aqueous solution was achieved.

View full abstract

The miscibility and interactions in blends of poly(N-vinylpyrrolidone) (PVP) and poly(styrene-co-methacrylic acid) (P(S-co-MAA)) with several MAA contents were investigated by DSC analyses and Fourier transform infrared (FT-IR) spectroscopy. It was found that PVP/P(S-co-MAA) blends were immiscible in most of blend compositions when MAA content of P(S-co-MAA) is smaller than 4.8 mol%. However, the miscible region of the PVP/(S-co-MAA) blends become wider with increasing MAA content in P(S-co-MAA). In addition, the PVP/ P(S-co-MAA) blends are miscible when MAA content of P(S-co-MAA) is larger than 12 mol%. It was suggested by FT-IR analyses that the miscibility of the PVP/P(S-co-MAA) blends were derived by associative interaction between carbonyl groups of PVP and MAA units of P(S-co-MAA).

View full abstract

Mechanical properties for four Nylon6 fibers of different diameters have been examined. The diameters of the fibers are 82, 24, 9.1(micro-fiber), and 2.5(super-micro-fiber)μm. The apparatus for the tensile test has been newly designed for measuring the mechanical properties of the super micro fiber. The breaking forces measured for many super micro fibers have been grouped into those with large and small values. The distribution of the breaking forces has been correlated to the distribution of the diameters. The super micro fiber has finally been clustered into five groups in order to evaluate mechanical properties. The breaking strength, breaking strain and the elastic modulus of super micro fiber at standard state were similar to those at wet.

View full abstract

Cellulose acetate films were uniaxially and simultaneous biaxially stretched at room temperature in the swell-wet agent bath, as previously, and then they were saponificated by alkali aqueous solution. The effects of stretching systems on the molecular orientation and mechanical properties of the stretched cellulose films were examined. Following results were obtained:
(1) The molecular chaos of the cellulose films uniaxially stretched with free width showed a uniaxial orientation with cylindrical symmetry around the stretching axis, and the anisotropy of mechanical properties in the machine direction was greater than that of the other samples by stretched systems.
(2) For the uniaxially stretched cellulose films with constant width, the molecular chaos showed a uniplanar-axial orientation, in which the chaos are oriented uniaxially to the stretching axis and also a certain crystallo-graphic plane is parallel to the film surface, and the anisotropy of mechanical properties was smaller than that of the films uniaxially stretched with free width.
(3) For the simultaneous biaxially stretched cellulose films, the molecular chaos showed a uniplanar orientation, which are random orientation within the films along with parallel to film surface, at all stretch ratios. The balanced mechanical properties, which were isotropic in the film plane regardless of the stretch ratio, were improved by stretching.

View full abstract