Graphene-based e-textiles have attracted great interest because of their promising applications in sensing, protection, and wearable electronics. Here, we report a scalable screen-printing process along with continuous pad-dry-cure treatment for the creation of durable graphene oxide (GO) patterns onto viscose nonwoven fabrics at controllable penetration depth. All the printed nonwovens show lower sheet resistances (1.2–6.8 kΩ/sq) at a comparable loading, as those reported in the literature, and good washfastness, which is attributed to the chemical cross-linking applied between reduced GO (rGO) flakes and viscose fibers. This is the first demonstration of tunable penetration depth of GO in textile matrices, wherein GO is also simultaneously converted to rGO and cross-linked with viscose fibers in our processes. We have further demonstrated the potential applications of these nonwoven fabrics as physical sensors for compression and bending.

This study covers the micro- and macrostructural changes that take place prior to and after foaming in polypropylene (PP). Four industrial grades of PP with varying molecular weights and amorphous contents were considered. Batch foaming of the samples was carried out using supercritical CO2 at three different temperatures, keeping the saturation pressure constant. A straight correlation between the cell size and the density of foams was drawn. Differential scanning calorimetry measurements in coherence with wide-angle X-ray analysis gave unique insights into the crystallinity of foams. Furthermore, dynamic mechanical analysis (DMA) showed shifts in the transition peaks of foamed PPs as compared with their corresponding unfoamed states. The tensile properties of foams of impact copolymers, foamed at low temperature, possessed superior tensile toughness to that of the foams obtained from homopolymers and random copolymers. This tensile characteristic of foams was in coherence with the DMA analysis.

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