Preparation and characterization of PA6/titania conductive fibres

The surface activity of TiO2 has been modified by using sodium hexametaphosphate to improve its dispersibility in matrix. The modified TiO2 nanoparticles have been mixed with polyamide 6(PA6) into granulation, and then white conductive fibres are prepared using different weight ratios by melt spinning. The as-spun fibres are characterized by using high insulation resistance meter, scanning electron microscopy, X-ray diffraction and differential scanning calorimeter. The results show that the treated conductive TiO2 material is well dispersed in the PA6 matrix with good compatibility and that the electrical conductivity of as-spun fibres is excellent. Considering the mechanism of its electrical conductivity,it is concluded that the conductive mechanism is tunnel when the TiO2 content is less than 5%, the mechanism is composition of both tunnel and ohmic when TiO2 content is between 10% and 15%, and it is ohmic conductive mechanism if the TiO2 content is more than 15%

Effect of disperse red dye on spectral red-shift of green-emitting luminous fibre

Green-emitting rare earth luminous fibre has been dyed with disperse red fluorescent dyestuff and ordinary disperse red dyestuff respectively, and the effects of disperse red dyestuffs on the spectral red-shift of green-emitting rare earth luminous fibre are studied by testing the luminescent properties. The emission spectra of green-emitting luminous fibre dyed with Red 3B, Red SE-GFL and Red S-2GFL show that the emission peak of fibre moves towards 620 nm from 520 nm after being dyed with Red 3B, and the spectrum has the strongest emission intensity when the concentration of Red 3B dye is 1.0% (o.w.f). The result of colorimetric analysis shows that the luminous fibre dyed with Red 3B dye at different concentrations has similar color purities, and the emission color of fibre is found closest to red color for the dyestuffs concentration of 1.0% (o.w.f). The analysis of energy transfer model of the dyed luminous fibre indicates that the light emitted by the SrAl2O4:Eu2+, Dy3+ phosphor could be used as a light source to excite the Red 3B dye, and the color of dyed luminous fibre is due to the blended luminescence color of the SrAl2O4: Eu2+, Dy3+ phosphor and Red 3B dye

Preparation and characterization of PA6/titania conductive fibres

150-155<span style="font-size:11.0pt;mso-bidi-font-size: 10.5pt;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" mso-bidi-font-family:mangal;position:relative;top:7.0pt;mso-text-raise:-7.0pt;="" letter-spacing:-.4pt;mso-font-kerning:16.0pt;mso-ansi-language:en-gb;="" mso-fareast-language:en-us;mso-bidi-language:hi"="" lang="EN-GB">The surface activity of TiO2 has been modified by using sodium hexametaphosphate to improve its dispersibility in matrix. The modified TiO2 nanoparticles have been mixed with polyamide 6(PA6) into granulation, and then white conductive fibres are prepared using different weight ratios by melt spinning. The as-spun fibres are characterized by using high insulation resistance meter, scanning electron microscopy, X-ray diffraction and differential scanning calorimeter. The results show that the treated conductive TiO2 material is well dispersed in the PA6 matrix with good compatibility and that the electrical conductivity of as-spun fibres is excellent. Considering the mechanism of its electrical conductivity, it is concluded that the conductive mechanism is tunnel when the TiO2 content is less than 5%, the mechanism is composition of both tunnel and ohmic when TiO2 content is between 10% and 15%, and it is ohmic conductive mechanism if the TiO2 content is more than 15%.</span

Influence of fluorescent pigments on the spectral characteristics of luminous coated fabrics

In recent years, luminous coated fabrics based on SrAl _2 O _4 : Eu ^2+ , Dy ^3+ luminescent materials have attracted more attention. However, due to the single emission color of SrAl _2 O _4 : Eu ^2+ , Dy ^3+ luminescent materials, the application of prepared coated fabrics has certain liminations. Therefore, at present, there is a need to develop a kind of luminous coated fabric which has the capability of emitting multiple colors of light. In this work, fluorescent pigments and SrAl _2 O _4 : Eu ^2+ , Dy ^3+ luminescent materials were added to a coating slurry and uniformly coated over a woven fabric substrate. The effects of adding fluorescent pigments on the spectral characteristics of luminous coated fabrics were evaluated. The blue fluorescent pigment causes a significant blue shift in the emission spectrum of the blue light-emitting coated fabric, whereas the emission spectra of the orange and red light-emitting coated fabrics exhibit a significant red shift. The yellow-green fluorescent pigments significantly affect the coated fabric. The emission spectrum shows no evident change and is similar to the emission spectrum of white (without any fluorescent pigment) luminescent coated fabric. The afterglow brightness of the colored luminous coated fabrics decreases exponentially with time. Adding blue fluorescent pigments has a greater impact on the brightness of the coated fabrics. The initial brightness is lower and the afterglow brightness loss is higher when using yellow-green fluorescence. The pigment has little effect on the brightness loss of coated fabrics, and the initial brightness of the coated fabric increases when adding yellow-green fluorescent pigments. Fluorescent pigments result in relatively low color purity for each colored coated fabric. However, the color rendering index is high, and the color rendering performance for the light source is excellent

A Heat-Stimulated Luminous Fiber Using Heat-Sensitive Green TF-G Pigment

In this study, we fabricated a heat-stimulated luminous fiber (HSLF) by wet spinning. The HSLF consists of Sr2ZnSi2O7: Eu2+, Dy3+ (SZSO), Y2O2S: Eu3+, Mg2+, Ti4+ (YOS), and heat-sensitive green TF-G pigment (HSGP). SZSO and YOS serve as a source of luminescence to yield a long afterglow system. HSGP is a heat-stimulating agent which develops the link between luminescence and temperature for HSLF. The luminescence of the HSLF is dull below 30 °C, but vivid above 30 °C. The luminescence of HSLFs can be stimulated by low heat (human body temperature). Emission spectra were recorded at 20 °C and 30 °C to investigate the heat-stimulated luminescent performance of HSLFs. HSLF is a smart material which can discern the exciting light to change color because of the photo-thermal effect. This characteristic provides optimum conditions for SZSO and YOS to store energy. The results demonstrated that most luminescence from SZSO and YOS could be absorbed by HSGP at 20 °C, but the luminescence could be liberated at 30 °C. The heat-stimulated phenomenon could also be verified by afterglow and the naked eye

Effect of disperse red dye on spectral red-shift of green-emitting luminous fibre

342-346Green-emitting rare earth luminous fibre has been dyed with disperse red fluorescent dyestuff and ordinary disperse red dyestuff respectively, and the effects of disperse red dyestuffs on the spectral red-shift of green-emitting rare earth luminous fibre are studied by testing the luminescent properties. The emission spectra of green-emitting luminous fibre dyed with Red 3B, Red SE-GFL and Red S-2GFL show that the emission peak of fibre moves towards 620 nm from 520 nm after being dyed with Red 3B, and the spectrum has the strongest emission intensity when the concentration of Red 3B dye is 1.0% (o.w.f). The result of colorimetric analysis shows that the luminous fibre dyed with Red 3B dye at different concentrations has similar color purities, and the emission color of fibre is found closest to red color for the dyestuffs concentration of 1.0% (o.w.f). The analysis of energy transfer model of the dyed luminous fibre indicates that the light emitted by the SrAl2O4:Eu2+, Dy3+ phosphor could be used as a light source to excite the Red 3B dye, and the color of dyed luminous fibre is due to the blended luminescence color of the SrAl2O4: Eu2+, Dy3+ phosphor and Red 3B dye

Effect of Geometry on Performance of Interlacer

Interlacer is the key part of interlacing technology that is adopted to improve the cohesion between loose multifilaments. Aimed at finding the interlacers with better performance, the present research designed five interlacers that can be classified into round type and cornered type. These five interlacers are different in cross-sectional shapes of yarn channel but are the same in the cross-sectional area. The evaluation of the performance of the interlacer includes the number and the strength of the tangles of the interlaced yarn it produces. Experiments are carried out at various supplied air pressures, yarn speeds and feed ratios. It was found that the interlacer with round cross-sectional shape of yarn channel is capable of producing an interlaced yarn with a large number of tangles and the cornered cross-sectional shape is effective in improving the strength of tangles. Among these five interlacers, the interlacer with an elliptical or an inverse-triangular shape has the best processing performanc

Disc swirl spinning — A novel approach

179-183A new spinning method ‘disc swirl spinning’, which consists of a combing roller drafting device, funnel fibre conveyer, disc fibre collector and swirl twister, has been developed. The spinning process, the design of the mechanism and its applications have been described and a preliminary comparative performance of the yarn quality analyzed. Scanning electron microphotographs of the disc swirl core-spun yarn have been compared with those of the air-jet spun and rotor-spun yarns. It is observed that the appearance of disc swirl core-spun yarn is similar to that of rotor-spun yarn, while the inner structure of the disc swirl core-spun yarn is found similar to that of the air-jet spun yarn. The breaking strength of disc swirl core-spun yarn is little lower than that of the ring core-spun yarn, while its breaking elongation CV﹪ is higher. The other quality parameters of the two kinds of yarn are found to be similar. The quality of the disc swirl core-spun yarn can basically meet the need of the processes