In order to study the effect of anisotropic feature of mechanical properties of various top sheet on the fabric hand, primary hand values and total hand value (=THV) were calculated from objective evaluation equation of various top sheets. Top sheet samples were classified into three groups as air-through, spunbond, and spunbond⁄meltblow groups. It was shown that THV became higher in the case of spunbnd top sheet in machine direction (=MD). THV was evaluated subjectively and objectively in the order of spunbond, spunbond⁄meltblow, air through, spunlace, woven fabrics. THV of spunbond top sheet in MD becomes the highest from both objective and subjective evaluations.
The preparation condition of poly(L-lactic acid) (PLLA)/ single-wall carbon nanotube (SWNT) composite films with highly dispersed SWNTs from solutions was examined and the thermo-mechanical properties of the resultant composite films were evaluated by tensile tests, DSC measurements and dynamic mechanical analyses. The dispersion of SWNTs in PLLA/SWNT composites significantly affected by the solvents used and the polymer concentrations. The PLLA/SWNT composite with the highest dispersion of SWNTs was obtained from a 5 wt% PLLA solution in chloroform. The tensile modulus and strength increased with increasing the SWNT content. The glass transition temperature shifted higher and the heat resistance remarkably improved with increasing the SWNT content. The PLLA/SWNT composite (PLLA-5) added with 5 wt% SWNT showed a glass transition temperature of 81°C and a storage modulus of 0.91 GPa at 100°C, which were 14°C and 3.3 times higher, respectively, than those pure PLLA film (PLLA-0). It is important to note that the rigid-amorphous fraction determined from the DSC thermogram increased with increasing the SWNT content suggesting the specific interaction between PLLA chains and SWNTs. The tensile modulus of 9.2 GPa for a PLLA-5 film drawn to an EDR of 9 was significantly higher than that of 7.2 GPa for the PLLA-0 drawn to the maximum achieved EDR of 12. These results indicate that the mixing of small amounts of SWNT (< 5 wt%) into a PLLA significantly improves the thermal stability and thermo-mechanical properties of PLLA films.
The sorption of natural thermosetting resin, Shellac, by the Kroy-finished wool and the effects of Shellac on enzymatic degradation and dyeability were investigated. The amounts of Shellac sorbed by the Kroy-finished and the regularly scoured wools were almost the same. Although the weight loss of the Kroy-finished wool by enzymatic degradation was significantly larger than that of the scoured wool, the values of strength retention for both wools were substantially the same at the same sorption amounts of Shellac. The color change and color fastness of the Shellac modified wools were tested for the fabrics dyed with three different acid dyes and three different reactive dyes. It was found that the sorption of Shellac on the Kroy-finished wool improves considerably the color fastness of rubbing and brings about the color change in higher levels as compared with the scoured wool. Present results obtained led to the conclusions that the sorption site of Shellac is the cell membrane complex (CMC) and Shellac retards enzymatic degradation for both the Kroy-finished and regularly scoured wools.
In this study, adsorption control and estimation of stimuli-reducing function of hydrophobic phospholipid polymer were carried out. The hydrophobic phospholipid polymer consisting of 2-methacryloyloxyethyl phosphorylcholine and stearyl methacrylate (PMS) was synthesized by ordinary radical polymerization. PMS nano-dispersion was prepared by the self-aggregation technique. Surface potential changes of PMS nano-dispersion were studied by laser-Doppler electrophoresis at pH conditions of 2 to 8. PMS nano-dispersion was positively charged under acidic conditions, and electrostatic adsorption to cotton fiber was observed by X-ray photoelectron spectroscopy (XPS) analysis. On the other hand, under neutral and basic conditions, non-charged and negatively charged nano-dispersions were not adsorbed. A fluorescence microscope observation of cotton fibers treated with PMS nano-dispersion that contained Nile Red suggested that a lamellar structure was formed in the PMS coat layer. The sulfur/carbon ratio (S/C) evaluated by XPS analysis showed that the amount of alkyl sulfate, which is a main component of laundry detergent, on the PMS treated cotton fibers was smaller than that on non-treated fibers after a laundry/rinse process. Cytotoxicity studies using three-dimensional skin models showed that the toxicity of surfactant was reduced by the PMS treatment.
A method to measure the three-dimensional deformation of fabrics by using an optical microscope tomography using magnified projections with various illumination directions is proposed. The CT reconstruction of the optical microscope tomography was simulated with a test phantom. A good image reconstruction was obtained with the test phantom (x:128×y:128×z:64 voxel) using a conjugate gradient algorithm with nonnegative constraint. To obtain good images reconstruction by using the optical microscope tomography, it is necessary that the number of projections is 12 or over and illumination directions are at an angle of 20 degrees or over to the optical axis of the optical microscope, and it is more desirable that the digital camera has 4096 different brightness levels (12bit) or over.