Flax yarn and polypropylene yarn were used as weft and warp, respectively, for producing interwoven fabric. Unidirectional flax fiber-reinforced composites with different fiber orientation such as (0)₆, (45)₆, (60)₆, (90)₆, and (0/90)s were fabricated by hot pressing method. The effects of different angle orientation such as parallel, off-axial, and cross lamination on tensile, flexural, and impact energy of unidirectional flax yarn composites were studied. Thermal behavior of fiber and composite was observed by thermo gravimetric analysis and differential scanning calorimetry. Tensile, flexural, and impact value of the composites are showing the decreasing trend for off-axial laminates compared to (0)₆axial-oriented laminates. Tensile and flexural strength values of (0)₆laminates are showing the maximum value such as 71 and 79 MPa, respectively. But, flexural strength value of ((0/90)s cross-ply arrangement is showing the reasonable value compared to off-axial lamination such as (45)₆, (60)₆, and (90)₆layup combination. Maximum impact energy value is observed around 334.66 J/m for (0)₆axial-oriented laminates. The influence of interwoven fabric on the processability of the composite fabrication is explained in detail. Fractography studies of the damaged surface are also demonstrated.

The management of the electromagnetic interference (EMI) of thin, light, and inexpensive materials is important for consumer electronics and human health. This paper describes the development of conductive films that contain a silver (Ag) flake powder and multiwall carbon nanotube (MWCNT) hybrid grid on a polytetrafluoroethylene (PTFE) film for applications that require electromagnetic shielding (EMS) and a conductive film. The Ag and MWCNT hybrid grid was constructed with a wire diameter and spacing of 0.5 mm. The results indicated that the proposed conductive films with 0.4 wt% MWCNTs had higher electromagnetic shielding effectiveness (EMSE) and electrical conductivity than those with other MWCNT loading amounts. The results also showed that the film with 0.4 wt% MWCNT loading had a high 62.4 dB EMSE in the 1800 MHz frequency and 1.81 × 10⁴ S/cm electrical conductivity. This combination improved stretchability, with 10% elongation at a 29% resistivity change rate. Conductive films with Ag/MWCNT electronic printing or lamination technologies could be used for EMI shielding and electrically conductive applications.

The triacetin and nitroglycerin barrier properties of layered-silicate reinforced ethylenepropylenediene monomer/chloroprene rubber (EPDM/CR) nanorubbers were investigated as rocket-propellant inhibitors. EPDM/CR nanorubbers with intercalated structures were formulated and prepared by the melt-compounding method. The triacetin permeability and nitroglycerin absorption were observed to decrease with increasing layered-silicate content. The layered silicates also improved the flame retardancies of the nanorubbers by forming silicate reinforced carbonaceous chars. Layered-silicate reinforced EPDM/CR nanorubbers are potentially effective rocket propellant-inhibiting materials.

The plasma treating process used to adjust the functional groups and modifying surface properties and mechanical behavior is a very important treatment method. Many researches have shown the results, especially in the versatility of polymer material fields. In this study, a pen-type radio frequency plasma system was used to modify the surface of various organic materials, such as polyester, polypropylene, and polyamide 6. Because of the short distance between two stainless steel electrodes, argon has been selected to trigger the plasma. The Taguchi method was used to decide the optimal combinations of the experimental parameters such as argon gas flow amount, plasma irradiation power and time, and the distance between the plasma torch and the organic fabric samples. The L₉ orthogonal arrays were also used to analyze the nine combinations of samples and achieve the optimal results for improving the hydrophilic ability of polyester, polypropylene, and polyamide 6. Then, the analysis of three different types of conductive resin coating on the matrix and surface resistance of the polyester, the 50d fabric type, exhibited much higher conductive ability. After washing, the fabric treated with poly-3,4-ethylenedioxythiophene showed higher decent resistance. The experimental results found that the surface resistivity of the polyester fabric would improve by three orders and the contact angle, until reaching 180°.

In flexible electronics, a highly electroconductive, flexible, and durable material is important for various applications. This study describes the property changes in graphene nanosheets (GNSs) doped into a conductive silver (Ag) paste that is used to form a grid-style pattern on a polyurethane hot melt film (PU HMF) for electromagnetic wave shielding. Electrical conductivity, thermal conductivity, and bending tests were performed for materials fabricated by an electronic printing method. The results showed that the conductive paste with a loading of 0.3 wt% GNSs (3SC) had good electromagnetic shielding effectiveness (EMSE, 49.9 dB at 1800 MHz), much better electrical conductivity (4.63*10⁴ S/cm) than the pure silver paste (1.38*10⁴ S/cm), and an improved bending ability. The coefficient of variation of GNS loading (3.01% to 3.80%) under 1000 cyclic bending tests was better than that of the pure silver paste (6.94%) at 2.4% strain, but the results under 500 cyclic elongation tests at 10.0% strain did not exhibit the same pattern. The coefficients of variation (CVs) of all samples in the GNS group (8.3–13.3%) were worse than those of the pure silver group (6.3%) after the elongation test. The reason for the differences in the electrical conductivity and flexibility was explained by the SEM results, which indicated notable damage after the bending and elongation tests. Woven fabrics laminated with a PU/Ag/GNS conductive film that were doped with different amounts of fillers were successfully manufactured by electronic printing and can be used for Electromagnetic Interference (EMI) shielding materials, electrodes for sensor components, wearable elements, smart home textiles, and conductive materials, for example.

This study showed an improvement in how functional groups activate on to the polymer surface by using the pen-type plasma treatment. These functional groups will graft on to the original polymer bonds and activate the surfaces of polymer products such as synthetic fabrics, films, and plastics. This research discussed the modifications of the hydrophilicity and conductivity in Polyamide 6 woven fabrics prior to and following the surface plasma treatment. First, without considering any processing, such as calendering, fabrics with the same denier but different numbers of filament were compared after the plasma treatment. The analysis of the experiment verifies that after the plasma treatment, the finer the filament the fiber has, the better improvements are obtained in the surface properties, such as hydrophilicity and surface resistivity. Next, after including the factor of calendering, the experiment also confirmed that the Polyamide 6 fabric processed with calendering exhibits better modification affects than those without it. In addition, the hydrophilicity modification result increases with irradiation time for fabrics treated with pen-type plasma, where the hydrophilicity modification benefit improves by 20–30%. Moreover, fabrics coated with poly-3, 4-ethylenedioxythiophene (PEDOT) are tested by washing. It has been confirmed that the washing resistance of the conductivity benefit appears to improve with the number of calendering times and irradiation time. The spectra show formation of COOH-groups (3300–2400 cm⁻¹), after impregnated acrylic acid process, and also show formation of O–H (alcohol) groups (3650–3200 cm⁻¹), after PEDOT coating.