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Nanoplasmonic hydrogen sensors are predicted to play a key role in safety systems of the emerging hydrogen economy. Pd nanoparticles are the active material of choice for sensor prototype development due to their ability to form a hydride at ambient conditions, which creates the optical contrast. Here, we introduce plasmonic hydrogen sensors made from a thermoplastic nanocomposite material, that is, a bulk material that can be molded with standard plastic processing techniques, such as extrusion and three-dimensional (3D) printing, while at the same time being functionalized at the nanoscale. Specifically, our plasmonic plastic is composed of hydrogensensitive and plasmonically active Pd nanocubes mixed with a poly(methyl methacrylate) matrix, and we optimize it by characterization from the atomic to the macroscopic level. We demonstrate meltprocessed deactivation-resistant plasmonic hydrogen sensors, which retain full functionality even after SO weeks. From a wider perspective, we advertise plasmonic plastic nanocomposite materials for application in a multitude of active plasmonic technologies since they provide efficient scalable processing and almost endless functional material design opportunities via tailored polymer- colloidal nanocrystal combinations.

Hemicelluloses are regarded as one of the first candidates for the development of value-added materials due to their renewability, abundance, and functionality. However, because most hemicelluloses are brittle, they can only be processed as a solution and cannot be processed using industrial melt-based polymer processing techniques. In this study, arabinoxylan (AX) was hydrophobized by incorporating butyl glycidyl ether (BuGE) into the hydroxyl groups through the opening of the BuGE epoxide ring, yielding alkoxy alcohols with terminal ethers. The formed BuGE derivatives were melt processable and can be manufactured into stretchable thermoplastic films through compression molding, which has never been done before with hemicellulose modified in a single step. The structural and thermomechanical properties of the one-step synthesis approach were compared to those of a two-step synthesis with a pre-activation step to demonstrate its robustness. The strain at break for the one-step synthesized AX thermoplastic with 3 mol of BuGE is ≈200%. These findings suggest that thermoplastic polymers can be composited with hemicelluloses or that thermoplastic polymers made entirely of hemicelluloses can be designed as packaging and stretchable electronics supports.

The impact of a small amount of polystyrene-b-poly(ethylene-co-butylene)-b-polystyrene (SEBS) on the thermomechanical and electrical properties of blends comprising low-density polyethylene (LDPE) and isotactic polypropylene (PP) is investigated. SEBS is found to assemble at the PP:LDPE interface as well as within isolated PP domains. The addition of 10 wt% SEBS significantly increases the storage modulus between the melting temperatures of the two polyolefins, 110 and 160°C, and results in improved resistance to creep during both tensile deformation as well as compression. Furthermore, the ternary blends display a very low direct-current (DC) conductivity as low as 3.4 × 10 S m at 70°C and 30 kV mm , which is considerably lower than values measured for neat LDPE. The here presented type of ternary blend shows potential as an insulation material for high-voltage direct current power cables.

The emergence of "green"electronics is a response to the pressing global situation where conventional electronics contribute to resource depletion and a global build-up of waste. For wearable applications, green electronic textile (e-textile) materials present an opportunity to unobtrusively incorporate sensing, energy harvesting, and other functionality into the clothes we wear. Here, we demonstrate electrically conducting wood-based yarns produced by a roll-to-roll coating process with an ink based on the biocompatible polymer:polyelectrolyte complex poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS). The developed e-textile yarns display a, for cellulose yarns, record-high bulk conductivity of 36 Scm-1, which could be further increased to 181 Scm-1 by adding silver nanowires. The PEDOT:PSS-coated yarn could be machine washed at least five times without loss in conductivity. We demonstrate the electrochemical functionality of the yarn through incorporation into organic electrochemical transistors (OECTs). Moreover, by using a household sewing machine, we have manufactured an out-of-plane thermoelectric textile device, which can produce 0.2 μW at a temperature gradient of 37 K.

Electrically conducting fibers and yarns are critical components of future wearable electronic textile (e-textile) devices such as sensors, antennae, information processors, and energy harvesters. To achieve reliable wearable devices, the development of robust yarns with a high conductivity and excellent washability is urgently needed. In the present study, highly conductive and machine-washable silk yarns were developed utilizing a Ag nanowire and PEDOT:PSS composite coating. Ag nanowires were coated on the silk yarn via a dip-coating process followed by coating with the conjugated polymer:polyelectrolyte complex PEDOT:PSS. The PEDOT:PSS covered the Ag nanowire layers while electrostatically binding to the silk, which significantly improved the robustness of the yarn as compared with the Ag nanowire-coated reference yarns. The fabricated conductive silk yarns had an excellent bulk conductivity of up to ∼320 S/cm, which is largely retained even after several cycles of machine washing. To demonstrate that these yarns can be incorporated into e-textiles, the conductive yarns were used to construct an all-textile out-of-plane thermoelectric device and a Joule heating element in a woven heating fabric. ispartof: ACS APPLIED MATERIALS & INTERFACES vol:12 issue:24 pages:27537-27544 ispartof: location:United States status: published

The most common type of extruded power cable insulation is based on cross-linked polyethylene (XLPE), which cannot be recycled as a thermoplastic material. Hence, thermoplastic insulation materials...

Abstract To realize the full gamut of functions that are envisaged for electronic textiles (e-textiles) a range of semiconducting, conducting and electrochemically active materials are needed. This article will discuss how metals, conducting polymers, carbon nanotubes, and two-dimensional (2D) materials, including graphene and MXenes, can be used in concert to create e-textile materials, from fibers and yarns to patterned fabrics. Many of the most promising architectures utilize several classes of materials (e.g., elastic fibers composed of a conducting material and a stretchable polymer, or textile devices constructed with conducting polymers or 2D materials and metal electrodes). While an increasing number of materials and devices display a promising degree of wash and wear resistance, sustainability aspects of e-textiles will require greater attention. Graphical abstract

Valorization of argi-waste polymers into value-added materials is essential for sustainable development of polymeric industry. Reported herein is a 1-step and 2-step strategy for fabrication of flexible and stretchable thermoplastics prepared by compression molding from two structurally different arabinoxylans (AX). The synthesis was accomplished using n-butyl glycidyl ether whose epoxide ring opened on hydroxyl group and resulted in introduction of alkoxide sidechains for the 1-step synthesis. AX was preactivated by periodate oxidation as 1st step for the 2-step synthesis. Two structurally different AXs, i.e. wheat bran extracted arabinoxylan (AXWB, araf/xylp=3/4) and barley husk extracted arabinoxylan (AXBH, araf/xylp=1/4) were used to understand the effects of the araf/xylp on thermoplastic properties because melt processability has been rare for low araf/xylp AXs. AXBH-derived samples demonstrated melt compression processability. AXWB and AXBH derived thermoplastics featured dual and single glass transition (Tg) characteristics respectively as confirmed by DSC and DMA, but AXBH derived thermoplastics had lower stretchability (maximum 160%) compared to AXWB samples (maximum 300 %). Higher araf/xylp and thus in turn longer alkoxide side chains in AXWB derived thermoplastics explained differences in stretchability.

Developing flexible, stretchable, and thermally processable materials for packaging and stretchable electronic applications from polysaccharide-based polymers contributes to the smooth transition of the fossil-based economy to the circular bioeconomy. We present arabinoxylan (AX)-based thermoplastics obtained by ring-opening oxidation and subsequent reduction (dA-AX) combined with hydrophobization with three different glycidyl ethers [n-butyl (BuGE), isopropyl (iPrGE), and 2-ethyl hexyl (EtHGE) glycidyl ether]. We also investigate the relationship between structural composition, thermal processing, and thermomechanical properties. BuGE- A nd iPrGE-etherified dA-AXs showed glass-transition temperatures (Tg) far below their degradation temperatures and gave thermoplastic materials when compression-molded at 140 °C. The BuGE (3 mol)-etherified dA-AX films at 19 and 31% oxidation levels show 244% (±42) and 267% (±72) elongation, respectively. In contrast, iPrGE-dA-AX samples with shorter and branched terminals in the side chains had a maximum of 60% (±19) elongation. No studies have reported such superior elongation of AX thermoplastic films and its relationship with molar substitution and Tg. These findings have implications on the strategic development of chemical modification routes using commercial polymer processing technologies and on fine-tuning structures and properties when specific polysaccharide-based polymers are used to engineer bio-based products for film, packaging, and substrates for stretchable electronic applications.

The thermoelectric power factor of a broad range of organic semiconductors scales with their electrical conductivity according to a widely obeyed power law, and therefore, strategies that permit this empirical trend to be surpassed are highly sought after. Here, tensile drawing of the conjugated polymer poly(3-hexylthiophene) (P3HT) is employed to create free-standing films with a high degree of uniaxial alignment. Along the direction of orientation, sequential doping with a molybdenum tris(dithiolene) complex leads to a 5-fold enhancement of the power factor beyond the predicted value, reaching up to 16 mu W m(-1) K-2 for a conductivity of about 13 S cm(-1). Neither stretching nor doping affect the glass transition temperature of P3HT, giving rise to robust free-standing materials that are of interest for the design of flexible thermoelectric devices. Funding Agencies|Swedish Research Council [2016-06146]; Knut and Alice Wallenberg Foundation through a Wallenberg Academy Fellowship; European Research Council (ERC) [637624]; U.S. National Science Foundation through the DMREF program [DMR-1729737]

Stretchable conducting materials are appealing for the design of unobtrusive wearable electronic devices. Conjugated polymers with oligoethylene glycol side chains are excellent candidate materials owing to their low elastic modulus and good compatibility with polar stretchable polymers. Here, electrically conducting elastomeric blend fibers with high stretchability, wet spun from a blend of a doped polar polythiophene with tetraethylene glycol side chains and a polyurethane are reported. The wet-spinning process is versatile, reproducible, scalable, and produces continuous filaments with a diameter ranging from 30 to 70 µm. The fibers are stretchable up to 480% even after chemical doping with iron(III) p-toluenesulfonate hexahydrate and exhibit an electrical conductivity of up to 7.4 S cm-1 , which represents a record combination of properties for conjugated polymer-based fibers. The fibers remain conductive during elongation until fiber fracture and display excellent long-term stability at ambient conditions. Cyclic stretching up to 50% strain for at least 400 strain cycles reveals that the doped fibers exhibit high cyclic stability and retain their electrical conductivity. Finally, a directional strain sensing device, which makes use of the linear increase in resistance of the fibers up to 120% strain is demonstrated.

To realize thermoelectric textiles that can convert body heat to electricity, fibers with excellent mechanical and thermoelectric properties are needed. Although poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is among the most promising organic thermoelectric materials, reports that explore its use for thermoelectric fibers are all but absent. Herein, the mechanical and thermoelectric properties of wet‐spun PEDOT:PSS fibers are reported, and their use in energy‐harvesting textiles is discussed. Wet‐spinning into sulfuric acid results in water‐stable semicrystalline fibers with a Young's modulus of up to 1.9 GPa, an electrical conductivity of 830 S cm−1, and a thermoelectric power factor of 30 μV m−1 K−2. Stretching beyond the yield point as well as repeated tensile deformation and bending leave the electrical properties of these fibers almost unaffected. The mechanical robustness/durability and excellent underwater stability of semicrystalline PEDOT:PSS fibers, combined with a promising thermoelectric performance, opens up their use in practical energy‐harvesting textiles, as illustrated by an embroidered thermoelectric fabric module.

[Image: see text] Because of their attractive mechanical properties, conducting polymers are widely perceived as materials of choice for wearable electronics and electronic textiles. However, most state-of-the-art conducting polymers contain harmful dopants and are only processable from solution but not in bulk, restricting the design possibilities for applications that require conducting micro-to-millimeter scale structures, such as textile fibers or thermoelectric modules. In this work, we present a strategy based on melt processing that enables the fabrication of nonhazardous, all-polymer conducting bulk structures composed of poly(3,4-ethylenedioxythiophene) (PEDOT) polymerized within a Nafion template. Importantly, we employ classical polymer processing techniques including melt extrusion followed by fiber spinning or fused filament 3D printing, which cannot be implemented with the majority of doped polymers. To demonstrate the versatility of our approach, we fabricated melt-spun PEDOT:Nafion fibers, which are highly flexible, retain their conductivity of about 3 S cm(–1) upon stretching to 100% elongation, and can be used to construct organic electrochemical transistors (OECTs). Furthermore, we demonstrate the precise 3D printing of complex conducting structures from OECTs to centimeter-sized PEDOT:Nafion figurines and millimeter-thick 100-leg thermoelectric modules on textile substrates. Thus, our strategy opens up new possibilities for the design of conducting, all-polymer bulk structures and the development of wearable electronics and electronic textiles.

Polar polythiophenes with oligoethylene glycol side chains are exceedingly soft materials. A low glass transition temperature and low degree of crystallinity prevents their use as a bulk material. The synthesis of a copolymer comprising 1) soft polythiophene blocks with tetraethylene glycol side chains, and 2) hard urethane segments is reported. The molecular design is contrary to that of other semiconductor‐insulator copolymers, which typically combine a soft nonconjugated spacer with hard conjugated segments. Copolymerization of polar polythiophenes and urethane segments results in a ductile material that can be used as a free‐standing solid. The copolymer displays a storage modulus of 25 MPa at room temperature, elongation at break of 95%, and a reduced degree of swelling due to hydrogen bonding. Both chemical doping and electrochemical oxidation reveal that the introduction of urethane segments does not unduly reduce the hole charge‐carrier mobility and ability to take up charge. Further, stable operation is observed when the copolymer is used as the active layer of organic electrochemical transistors., A soft polythiophene with tetraethylene glycol side chains is copolymerized with hard urethane blocks. The copolymer exhibits improved ductility and stiffness, owing to a reversible network formed through hydrogen‐bonding between urethane segments, while electrical and electrochemical properties are retained to a great extent. The hydrogen‐bonded network reduces the degree of swelling of the copolymer as compared to the homopolymer.

Conducting polymers offer new opportunities to design soft, conformable and light-weight thermoelectric textile generators that can be unobtrusively integrated into garments or upholstery. Using the widely available conducting polymer:polyelectrolyte complex poly (3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) as the p-type material, we have prepared an electrically conducting sewing thread, which we then embroidered into thick wool fabrics to form out-of-plane thermoelectric textile generators. The influence of device design is discussed in detail, and we show that the performance of e-textile devices can be accurately predicted and optimized using modeling developed for conventional thermoelectric systems, provided that the electrical and thermal contact resistances are included in the model. Finally, we demonstrate a thermoelectric textile device that can generate a, for polymer-based devices, unprecedented power of 1.2 μW at a temperature gradient ΔT of 65 K, and over 0.2 μW at a more modest ΔT of 30 K. ispartof: Journal Of Power Sources vol:480 status: Published online

Organic semiconductors are the centerpiece of several vibrant research fields from single-molecule to organic electronics, and they are finding increasing use in bioelectronics and even classical polymer technology. The versatile chemistry and broad range of electronic functionalities of conjugated materials enable the bridging of length scales 15 orders of magnitude apart, ranging from a single nanometer (10-9 m) to the size of continents (106 m). This work provides a taste of the diverse applications that can be realized with organic semiconductors. The reader will embark on a journey from single molecular junctions to thin film organic electronics, supramolecular assemblies, biomaterials such as amyloid fibrils and nanofibrillated cellulose, conducting fibers and yarns for e-textiles, and finally to power cables that shuffle power across thousands of kilometers.

[Image: see text] Free-standing bulk structures encompassing highly doped conjugated polymers are currently heavily explored for wearable electronics as thermoelectric elements, conducting fibers, and a plethora of sensory devices. One-step manufacturing of such bulk structures is challenging because the interaction of dopants with conjugated polymers results in poor solution and solid-state processability, whereas doping of thick conjugated polymer structures after processing suffers from diffusion-limited transport of the dopant. Here, we introduce the concept of thermally activated latent dopants for in situ bulk doping of conjugated polymers. Latent dopants allow for noninteractive coprocessing of dopants and polymers, while thermal activation eliminates any thickness-dependent diffusion and activation limitations. Two latent acid dopants were synthesized in the form of thermal acid generators based on aryl sulfonic acids and an o-nitrobenzyl capping moiety. First, we show that these acid dopant precursors can be coprocessed noninteractively with three different polythiophenes. Second, the polymer films were doped in situ through thermal activation of the dopants. Ultimately, we demonstrate that solid-state processing with a latent acid dopant can be readily carried out and that it is possible to dope more than 100 μm-thick polymer films through thermal activation of the latent dopant.

The development of an entirely polymer-based motion sensing glove with possible applications, for example, in physical rehabilitation is described. The importance of comfort for the wearer and the possibility to clean the glove in normal laundering processes were important aspects in the development. The glove is all textile and manufactured using materials and methods suitable for standard textile industry processes. For the first time, melt-spun piezoelectric poly(vinylidene fluoride) (PVDF) fibers with conductive cores were machine embroidered onto a textile glove to function as a sensor element. Electrodes and electrical interconnections were constituted by a screen printed conductive poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) formulation. The screen printing of the interconnections was shown to be a reliable method for reproducible material deposition, resulting in an average surface resistivity value of 57 Ω/square. A repeated strain of 10% only influenced the resistance of the interconnections initially and to a very limited extent. The influence of washing on the electrical resistance of the printed interconnections was also studied; after 15 wash cycles the average surface resistivity was still below 500 Ω/square, which was deemed sufficient for the polymeric sensor system to remain functional during long-term use. Sensor data from the glove was also successfully used as input to a microcontroller running a robot gripper, in order to demonstrate its potential applications.

Thermoelectric textiles that are able to generate electricity from heat gradients may find use as power sources for a wide range of miniature wearable electronics. To realize such thermoelectric textiles, both p- and n-type yarns are needed. The realization of air-stable and flexible n-type yarns, i.e., conducting yarns where electrons are the majority charge carriers, presents a considerable challenge due to the scarcity of air-stable n-doped organic materials. Here, we realize such n-type yarns by coating commercial sewing threads with a nanocomposite of multiwalled carbon nanotubes (MWNTs) and poly(N-vinylpyrrolidone) (PVP). Our n-type yarns have a bulk conductivity of 1 S cm–1 and a Seebeck coefficient of −14 μV K–1, which is stable for several months at ambient conditions. We combine our coated n-type yarns with poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) dyed silk yarns, constituting the p-type component, to realize a textile thermoelectric module with 38 n/p elements, which are capable of producing an open-circuit voltage of 143 mV when exposed to a temperature gradient of 116 °C and a maximum power output of 7.1 nW at a temperature gradient of 80 °C.

Durable, electrically conducting yarns are a critical component of electronic textiles (e-textiles). Here, such yarns with exceptional wear and wash resistance are realized through dyeing silk from the silkworm Bombyx mori with the conjugated polymer:polyelectrolyte complex PEDOT:PSS. A high Young’s modulus of approximately 2 GPa combined with a robust and scalable dyeing process results in up to 40 m long yarns that maintain their bulk electrical conductivity of approximately 14 S cm–1 when experiencing repeated bending stress as well as mechanical wear during sewing. Moreover, a high degree of ambient stability is paired with the ability to withstand both machine washing and dry cleaning. For the potential use for e-textile applications to be illustrated, an in-plane thermoelectric module that comprises 26 p-type legs is demonstrated by embroidery of dyed silk yarns onto a piece of felted wool fabric.

This study reports on the poling and characteristics of a melt-spun piezoelectric bicomponent fiber with poly(vinylidene fluoride) (PVDF) as its sheath component and a conductive composite with car ...

Analysis of the torsion angle distribution of poly(vinylidene fluoride) (PVDF) structures at temperatures above its melting point is addressed by combining first principles methods, atomistic simulations and laboratory experiments. Amorphous, alpha- and beta-conformations of PVDF structures have been considered. The results from the atomistic simulations as well as the experiments show that there is a larger probability of the PVDF torsions to be near +/- 180 degrees at temperatures above the melting point, which is associated more with the beta-conformation than the alpha-conformation.

Nanoclay and carbon nanotubes (CNT) have been in focus recently as means of enhancing β phase crystals formation in poly(vinylidene fluoride)(PVDF). Dominantly, the so-far work has been carried out on films/thin sheets filled with nanoclay. It has been found, mainly from combined XRD and DSC data, that nanoclay influences the PVDF structure, and particularly the β phase crystals formation is enhanced. Results published by various groups are in fairly good agreement. There are no results for nanoclay filled melt-spun PVDF fibres.The influence of CNT on PVDF structure has been less studied. XRD data indicating an enhancing role of multi-wall carbon nanotubes (MWNT) on β phase crystals formation in solution compounded PVDF films are available. Published results for MWNT/PVDF films are not in good agreement. The only study into single-wall carbon nanotube (SWNT)/PVDF has been made on electrospun nanofibres.We explore above findings towards melt-spun nanofilled PVDF fibres. We present new results obtained by us for melt-spun PVDF fibres containing non-functionalized and amino-functionalized double-wall carbon nanotubes (DWNT). The key finding is that amino-DWNT can influence the β to α polymorphic balance.

When poly(vinylidene fluoride) (PVDF) is to be used as a piezoelectric material, the processing must include the formation of polar beta-phase crystallites, as well as the application of electrically conducting charge collectors, that is, electrodes. In this article, results from the melt spinning of PVDF yarns and a novel bicomponent PVDF-yarn with a conductive carbon black/polypropylene (CB/PP) core are presented. Melt spinning has been done under conditions typical for industrial large-scale fiber production. The effects on the resulting crystalline structure of varying the spinning velocity, draw rate, and draw temperature are discussed. The results show that, for maximum alpha-to-beta phase transformation, cold drawing should take place at a temperature between 70 and 90 degrees C, and both the draw ratio and the draw rate should be as high as possible. It was observed that the cold drawing necessary to form beta-phase crystallinity simultaneously leads to a decrease in the core conductivity of the bicomponent yarns. In this work, the melt spinning of bicomponent fibers with high-beta-phase PVDF in the sheath and a CB/PP core was successfully accomplished. The core material remained electrically conductive, paving the way for the use of a CB-polymer compound as inner electrode in the melt spinning of piezoelectric bicomponent fibers.

KGaA, Weinheim Textiles are a promising base material for flexible and wearable electronic applications such as sensors, actuators, and energy harvesters. An essential component in such electronic textiles (e-textiles) is electrically conducting yarns. Here, a continuous dyeing process is presented to convert an off-the-shelf silk sewing thread into a wash and wear resistant functional thread with a conductivity of about 70 S cm−1; a record high value for coated yarns. An aqueous ink based on the conducting polymer:polyelectrolyte complex poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) is modified, to produce more than 100 m of dyed conducting threads, which are subsequently converted into e-textiles by both hand weaving and machine embroidery. The yarns are resistant to abrasion and wear, and can be machine washed at least 15 times with retained electronic properties. The woven fabric is used to design a capacitive touch sensor which functions as an e-textile keyboard.

Multi-wall carbon nanotubes (MWNT) were used as reinforcement for melamine-formaldehyde (MF). They were oxidised in HNO3/ H2SO4 mixture and analyzed by means of X-ray Photoelectron Spectroscopy (XPS). Two anionic surfactants: sodium dodecyl sulphate (SDS) and sodium dodecylbenzenesulfonate (NaDDBS) were used to assist the dispersion of nanotubes. The MWNT content was varied from 0 to 1.0 wt%, and the influence of nanotubes on viscosity (flow curves) was measured. The viscosity of SDS-assisted aqueous solution of MF containing a small amount (0.1 wt%) of MWNT is low, and thus promising towards manufacturing processes. A film stacking-like manufacturing route was adapted to prepare ternary MWNT/cellulose/MF thin composite layers. Transmission electron microscopy (TEM) and Light microscopy (LM) were used to observe dispersion. The addition of 0.1 wt% MWNT assisted with SDS increased the storage modulus and tensile strength by 50%. Conventional calculations of the Young's modulus were made. Values underestimating the modulus were found. The observed discrepancy was attributed to polymer chain immobilisation as a result of crosslinking.

We here present results and analysis from a study of affective tactile communication between human and humanoid robot (the NAO robot). In the present work, participants conveyed eight emotions to the NAO via touch. In this study, we sought to understand the potential for using a wearable affective (tactile) interface, or WAffI. The aims of our study were to address the following: (i) how emotions and affective states can be conveyed (encoded) to such a humanoid robot, (ii) what are the effects of dressing the NAO in the WAffI on emotion conveyance and (iii) what is the potential for decoding emotion and affective states. We found that subjects conveyed touch for longer duration and over more locations on the robot when the NAO was dressed with WAffI than when it was not. Our analysis illuminates ways by which affective valence, and separate emotions, might be decoded by a humanoid robot according to the different features of touch: intensity, duration, location, type. Finally, we discuss the types of sensors and their distribution as they may be embedded within the WAffI and that would likely benefit Human-NAO (and Human-Humanoid) interaction along the affective tactile dimension. Design, textil och hållbar utveckling

The effect of melt spinning and cold drawing parameters on the formation of β-phase crystallinity in Poly(Vinylidene Fluoride) (PVDF) fibres, and ways of increasing such crystallinity, were studied. Fibres were melt-spun using four different melt draw ratios, and subsequently cold-drawn at different draw ratios. The maximum draw ratio in cold drawing was dependent on the draw ratio used in the melt spinning. The crystalline structure of the fibres was studied mainly by DSC and XRD. Results showed that the degree of crystallinity in the fibres was determined by the melt draw ratio, and that before cold drawing the crystalline structure of the fibres was predominantly in the α form. By cold drawing, α-phase crystallites could be transformed into the β-phase. It was established that, at certain conditions of melt spinning and cold drawing, PVDF fibres containing up to 80% of mainly β form crystallinity can be prepared. It is further proposed that fibres spun at a sufficiently high melt draw ratio consist to a large extent of extended-chain crystals, and this greatly affects the melting point of the PVDF. Thus DSC melting point data were shown to be insufficient to determine the crystalline phase of PVDF.