Nowadays, thanks to the electrospinning process, polymeric fibers in nanoscale diameters (10–500 nm) are easily producible. During the last decade, the electrospinning technique has been greatly investigated and developed. One of the most important fields of study on the electrospinning process is the influence of effective parameters on electrospun nanofibers and nanoweb properties. In this study, using polyamide-6 (PA-6)/formic acid polymer solution, three important parameters of the electrospinning process, including polymer solution concentration, needle-tip-to-collector distance, and needle length, were precisely studied. The solution concentration is a very important parameter that affects the nanowebs’ homogeneity and nanofibers’ diameter evenness. Scanning electron microscopy (SEM) analysis of the electrospun nanowebs showed that among five polymer solution concentrations (5, 10, 15, 20, and 25 wt%), 25 wt% was more suitable and provided the homogeneity and reproducibility of PA-6 nanowebs. It has been found that the needle-tip-to-collector distance had a considerable influence on the nanofibers’ diameter and the nanoweb collection zone. Morphological investigation and statistical studies showed that the nanofibers’ diameter increased with the reduction of the needle-tip-to-collector distance. Moreover, the average diameter of the nanoweb collection zone decreased by the reduction of this distance. The effect of needle length on the nanofibers’ morphology and nanowebs’ collection zone was investigated. Statistical analysis of the obtained results revealed that the increase of needle length significantly increased the average nanofibers’ diameter. Inversely, the diameter of the nanoweb collection zone reduced when needle length increased. All previously mentioned studies helped to define the optimal electrospinning condition to produce the bead-free, non-branched, and homogeneous PA-6 electrospun nanofibers and nanowebs.

Fabric inspection has an importance to prevent the risk of delivering inferior quality product. Until recently, the process was still undertaken offline and manually by humans, which has many drawbacks. The continuous development in computer technology introduces the automated fabric inspection as an effective alternative. In our work, Fast Fourier Transform and Cross-correlation techniques, i.e. linear operations, are first implemented to examine the structure regularity features of the fabric image in the spatial domain. To improve the efficiency of the technique and overcome the problem of detection errors, further thresholding operation is implemented using a level selection filter. Through this filter, the technique is able to detect only the actual or real defects and highlight its exact dimensions. A software package such as Matlab or Scilab is used for this procedure. It is implemented firstly on a simulated plain fabric to determine the most important parameters during the process of defect detection and then to optimize each of them even considering noise. To verify the success of the technique, it is implemented on real plain fabric samples with different colors containing various defects. Several results of the proposed technique for the simulated and real plain fabric structures with the most common defects are presented. Finally, a vision-based fabric inspection prototype that could be accomplished on-loom to inspect the fabric under construction with 100% coverage is proposed.

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A new computer model is developed to predict the tensile behavior of nonwoven fabrics from the stress-strain behavior of their constituent fibers and distributions of fiber orientation angles. The finite element method is used to calculate the numerical solution of stress and strain distribution in different regions of the samples during tensile deformation. Stress-strain curves of fabrics are simulated. Tensile testing is done on several nonwoven fabrics to verify the simulated results, which are in a good agreement with those obtained from tensile experiments.

In this study, the bundle elongation and tenacity of cotton fibers were measured using a modified tensile testing instrument to which Pressley clamps (1/8” gage length) were adapted. 32 cotton genotypes with a range of bundle tenacity and elongation were carefully selected based on their distinct physical properties. The work of rupture was calculated from the load vs. elongation curves for each type of cotton. Results demonstrated the importance of fiber bundle elongation in the work of rupture of fiber bundles, which is critically important to processing performance. This study lays a foundation for future efforts to calibrate the high volume instrument elongation measurements and to breed new cultivars with improved work of rupture. This should result in lower fiber breakage when the cotton fibers are submitted to different mechanical stresses (ginning, carding, spinning, and weaving).

The study is focused on the water diffusion phenomenon through the Raffia vinifera fibre from the stem. The knowledge on the behavior of those fibres in presence of liquid during the realization of biocomposite, is necessary. The parameters like percentage of water gain at the point of saturation, modelling of the kinetic of water absorption, and the effective diffusion coefficient were the main objectives. Along a stem of raffia, twelve zones of sampling were defined. From Fick's 2nd law of diffusion, a new model was proposed and evaluated compared to four other models at a constant temperature of 23°C. From the proposed model, the effective diffusion coefficient was deduced. The percentage of water gain was in the range of 303–662%. The proposed model fitted better to the experimental data. The estimated diffusion coefficient was evaluated during the initial phase and at the final phase. In any cross section located along the stem of Raffia vinifera, it was found that the effective diffusion coefficient increases from the periphery to the centre during the initial and final phases.

A lot of fibre and fabric structures or finishing parameters influence the functional properties of fabrics. In order to assess the thermal properties of conventional polyester and microfibre types of fabrics the plate/fabric/plate method for conductivity or cool/warm feeling was used. Fabrics made of microfibres show lower heat conductance and therefore higher thermal insulation properties. Microfibre fibres exhibit a warmer feeling than conventional polyester fabrics depending on pressure, which may be due to the difference in the fibre and fabric surface in contact with the human skin.