Smart textiles are fabrics able to sense external conditions or stimuli, to respond and adapt behaviour to them in an intelligent way and present a challenge in several fields today such as health, sport, automotive and aerospace. Electrically conductive textiles include conductive fibres, yarns, fabrics, and final products made from them. Often they are prerequisite to functioning smart textiles, and their quality determines durability, launderability, reusability and fibrous performances of smart textiles. Important part in smart textiles development has conductive polymers which are defined as organic polymers able to conduct electricity. They combine some of the mechanical features of plastics with the electrical properties typical for metals. The most attractive in a group of these polymers are polyaniline (PANI), polypyrrole (PPy) and poly(3,4-ethylenedioxythiophene) (PEDOT) as one of the polythiophene (PTh) derivatives. Commercially available smart textile products where conductive polymers have crucial role for their development are medical textiles, protective clothing, touch screen displays, flexible fabric keyboards, and sensors for various areas. This paper is focused on conductive polymers description, mechanism of their conductivity, and various approaches to produce electrically conductive textiles for smart textiles needs. Commercial products of conductive polymers-based smart textiles are presented as well as the objective of a number of lab-scale items.

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The island of New Guinea is the result of continent-arc collision that began building the island's Central Range during the late Miocene. Recent studies have shown that rapid subduction, uplift and exhumation events took place in response to rapid, oblique convergence between the Pacific and the Australian plates. The tectonic and sedimentary evolution of Cenderawasih Bay, in the northwestern part of the New Guinea Island is still poorly understood: this bay links a major structural block, the Kepala Burung block, to the island's Central Ranges. Previous studies have shown that Cenderawasih Bay contains a thick (> 8 km) sequence of undated sediments. One hypothesis claims that the embayment resulted from a 3 Ma opening created by anticlockwise rotation of the Kepala Burung block with respect to the northern rim of the Australian plate. Alternatively, the current configuration of Cenderawasih Bay could have resulted from the southwest drift of a slice of volcanics and oceanic crust between 8 and 6 Ma. We test these hypotheses using i) a geomorphologic analysis of the drainage network dynamics, ii) a reassessment of available thermochronological data, and iii) seismic lines interpretation. We suggest that sediments started to accumulate in Cenderawasih Bay and onshore in the Waipoga Basin in the late Miocene since the inception of growth of the Central Range, beginning at 12 Ma, resulting in sediment accumulation of up to 12200 m. This evidence is more consistent with the second hypothesis, and the volume of sediment accumulated means it is unlikely that the embayment was the result of recent (2-3 Ma) rotation of structural blocks. At first order, we predict that infilling is mainly composed of siliciclastics sourced in the graphite-bearing Ruffaer Metamorphic Belt and its equivalent in the Weyland Overthrust. Ophiolites, volcanic arc rocks and diorites contribute minor proportions. From the unroofing paths in the Central Range we deduce two rates of solid phase accumulation (SPAR) since 12 Ma, the first one at a mean SPAR ranging between 0.12-0.25 mm/a with a maximum SPAR of 0.23-0.58 mm/a, and the second during the last 3 Ma, at a mean SPAR ranging between 0.93-1.62 mm/a and with a maximum SPAR between 2.13-3.17 mm/a, i.e., 6700-10000 m of Plio-Pleistocene sediment accumulation. Local transtensional tectonics may explain these unusually high rates of sedimentation in an overall sinistral oblique convergence setting.

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Three-dimensional preforms have been developed in order to remedy and minimize the out-of-plane damage caused by 2D structures. Several researches have been done on more complex structures which have more interesting mechanical characteristics through-the-thickness. A wide spectrum of 3D textile technologies encompassing weaving, knitting, stitching, z-pinning, tufting, etc. is used to manufacture through-the-thickness reinforced materials. This kind of reinforcement aims to achieve a balance between the in-plane and out-of-plane properties. Recently, tufting shows more opportunities to develop through-the-thickness reinforcements especially with the advances in devices from manual to fully automatic. In literature, the mechanical behaviour of tufted composites has been one of the main subjects, however, few studies outline the mechanical behaviour of dry tufted fabrics. Dry stage is an essential step to understand the influence of through-the-thickness reinforcement and the formability of multilayer preforms. In this context, the present paper reviews the various technologies of through-the-thickness reinforcement as well as the microstructural defects related to both the impregnation and the kind of reinforcement. Also, this work highlights the mechanical performance of tufted 3D structures at dry and composite scales.

The tensile behaviour of braid reinforcement is classically described by the behaviour of composite elaborated from these reinforcements. Few studies concern the tensile behaviour of braided fabrics. In this paper biaxial and triaxial braids are manufactured on a braiding loom. The evolution of key parameters as linear mass and braiding angle in function of process parameters is presented. Braid reinforcements are characterized in uniaxial tensile. The mechanical behaviour is analysed and compared in function of the braiding angle, but also different kinds of braid are considered. A specific behaviour called ''double-peak'' is identified for triaxial braids which have a higher braiding angle. The evolution of the braiding angle measured during tensile tests gives a comprehension on the mechanical behaviour of dry braids. Associated with this experimental study, an analytical model is also proposed, to predict mechanical properties of braid reinforcements.

Natural flax fibres have been extensively recognized by automotive industries to reduce the weight of vehicles and obtain recyclable composite parts. Most of composite parts are produced by using resin transfer moulding or thermoforming processes. As the first step of these two composite manufacturing processes, the preforming is quite important. Braided and woven fabrics are widely used as textile reinforcements to manufacture the advanced composite parts. But few research works concern the preforming of the reinforcements based on natural fibres and also there is no analysis of dry braided fabrics forming. In the present work, the studies of formability behaviour of braided and woven fabrics made of the same flax/polyamide 12 commingled yarns are performed. Furthermore, an experimental comparison between the preforming behaviour of braided and woven flax/polyamide fabrics is investigated under identical preforming conditions. The different formability behaviour and the defects developed during preforming stage are analysed. First results obtained on hemispherical shape show a higher deformability for the braided reinforcements, which can generate some forming defects, in particular buckles.