Mobility is one of the most important factors for garment design. In this paper, we examined the relationship between joint torque and mobility with cloth samples of different elongation at maximum tensile force (EMT) by motion measurement and sensory test. In the experiment, twenty subjects bent and stretched their arms with the cloth sample attached. In the motion measurement, the elbow joint torque was calculated on the basis of acceleration and angular velocity measured by sensors on the hand, forearm, and upper arm. In addition, impressions including “elbow flexibility”, “elbow extensibility”, “restraint feeling”, and “mobility” were evaluated by paired comparison test. As a result, the low EMT cloth was found to have high joint torque power, which is required for motion, and it was evaluated to give an excessive restrained feeling. On the other hand, the high EMT cloth was found to have low joint torque power, and it was evaluated to be flexible and ease of movement. Therefore, there was a tendency that the impressions of elbow flexibility and mobility were lower with increase of joint torque power. The results indicate that joint torque power is effective for quantitatively evaluating the mobility of garments.

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Fiber‐reinforced single‐polymer composites were fabricated through the compression molding of sheath‐core bicomponent fibers consisting of low and high molecular weight poly(ethylene terephthalate), LMPET and HMPET, as the sheath and core components, respectively. The LMPET/HMPET bicomponent fibers were prepared through the high‐speed melt spinning process. When the take‐up velocity exceeded a certain level, orientation‐induced crystallizaion started to occur in the HMPET while the LMPET remained in an amorphous state. After the starting of the crystallization of the HMPET in the melt spinning process, orientation relaxation of the LMPET proceeded. Accordingly, the sheath‐core fibers consisting of the highly oriented and crystallized core component (HMPET) and the amorphous and low oriented sheath component (LMPET) were obtained. Compression molding of such sheath‐core fibers was conducted at a temperature above the glass transition temperature and below the melting temperature of PET where the rubbery softening of the amorphous phase was utilized for the fusion of the sheath component to form matrix phase while maintaining the well‐developed fiber structure of the core component intact. The fabricated fiber‐reinforced single‐polymer composites showed fairly high mechanical properties. Good recyclability of the composites is expected because the composites are consisting of only pure PET.

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Activated carbon fiber (ACF) was oxidized by different concentrations of HNO3 solution and different contact time. Both the original and the oxidized ACFs were tested to adsorb Pb(II) from aqueous solution. Properties of ACFs were characterized by BET surface area, elemental analysis, Boehm titration and the pH of the point of zero charge (pH_pzc). The results showed that the maximum adsorption ability of Pb(II) on the oxidized ACF was 0.34 mmol/g at pH 3.0, which was 3 times larger than that on the original ACF, and was enhanced to 0.96 mmol/g by increasing the solution pH from 3.0 to 5.9. The adsorption isotherm of all ACFs obeyed the Langmuir isotherm model. Moreover, the Pb(II) adsorption rate for the oxidized ACF was about 3‐fold faster than that of the original ACF.

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Cotton fabrics were oxidized with TEMPO/NaClO/NaClO₂ or 4‐acetamido‐TEMPO/NaClO/NaClO₂ system in water at pH 3.8 or 6.8 and 40-80℃ for 0-120 min. As references, cotton fabrics were oxidized with TEMPO/NaBr/NaClO system in water at pH 10 and room temperature for 0-45 min. In all cases, the higher the carboxylate content of the oxidized cotton fabric, the lower its viscosity‐average degree of polymerization (DP_v). However, the oxidation at pH 3.8 and 6.8 gave cotton fabrics with higher DP_v values at carboxylate contents > 0.3 mmol/g, compared to those prepared at pH 10. When the cotton fabrics oxidized with 4‐acetamido‐TEMPO/NaClO/NaClO₂ system in water at pH 3.8 or 6.8 were heated at 105℃ for 2 h, clear whiteness reductions were observed, a part of which may have been caused by thermal degradation of 4‐acetamido‐TEMPO‐related compounds physically adsorbing on the oxidized cotton fabrics and slightly remaining in them even after repeated washing with water. When ethylene glycol, gluconic acid or glucose was directly added to the aqueous solution containing the cotton fabric after the oxidation, the oxidized cotton fabrics had relatively low whiteness reduction and low bending resistance (or better softness for clothes) even after heating at 105℃ for 2 h. Thus, the TEMPO‐ or 4‐acetamido‐TEMPO‐mediated oxidation in water at pH 3.8 or 6.8 may be applicable to chemical modification of cotton fabrics to be used as clothes for functionalized underwear.

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