This study examines the feasibility of co-electrospinning vapor grown carbon nanofibers (VGNF) within thermoplastic elastomer. The reinforcement effect was studied. The diameter of the thermoplastic elastomer was found to range from 0.5 to 3 μm. The mechanical properties of the electrospun fibrous structure were found to be similar to that of cast elastomeric films. However, the electrospun fibrous membranes have superior tactile properties. The addition of VGNF significantly increases the bulkiness of the fibrous elastomeric membranes.

Examination was made of different tensile properties of wet natural cellulose fiber (cotton) and regenerated cellulose fibers (rayon filament). Influence of the crystal region and molecular weight on tensile properties was investigated using mercerized and acid hydrolyzed cotton fibers. No influence of crystal region on tensile properties of cotton fiber was found. The effect of moisture regain on the strength and elongation of cotton decreased with decreasing molecular weight. The slope in the plot of tensile properties against moisture regain became negative, when the molecular weight of the cellulose approximated that of rayon. Changes in tensile strength and elongation with wetting may depend mainly on the number of the molecular chain ends in the amorphous region.

Structural models of yarn, plain weave fabrics, and plain weave fabric/resin composites were derived and theoretical formulas for the effective thermal conductivity were developed from these models. First the effective thermal conductivity of the transverse direction of the yarn was obtained by using the effective thermal conductivity of the fiber. Then the effective thermal conductivity in the direction of the thickness of both plain weave fabrics and composite materials was calculated from the yarn thermal conductivity. Also, we analyzed heat flow in plain weave fabrics using the finite element method. Heat flows not only in the direction transverse to the yarn, but also in the parallel direction, however heat flow in the direction of the thickness of the plain weave fabric became only twice that calculated by assuming that heat does not flow in the direction parallel to of the yarn at all. We confirmed that the heat conduction anisotropy of fibers must be considered when designing the effective thermal conductivity of plain weave fabrics and of plain weave fabric/resin composites.

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