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Poly(3,4-ethylenedioxythiophene) (PEDOT) is a highly valuable polymer material for modern electronics due to its impressive electrical conductivity (up to 1000 S.cm−1). Combined with poly(styrenesulfonate) (PSS), PEDOT can beprocessed into thin film for a multitude of applications [1]. However, the introduction of PEDOT in melt-state processes of the plastic industryis still challenging because PEDOT is infusible and only commercially available as highly diluted aqueous solutions. Nevertheless, previous study showed that extrusion processing of PEDOT:PSS solutions with PEO as a melting carrier is possiblebut sophisticated pre/post-treatments are mandatory to maintain high level of electrical conductivity up to 5 S.cm−1 [2]. In this context, the goal of this study is to synthesize electrically conductive polymeric particles of PEDOT. An oxidative chemical polymerization of EDOT was carried out using two different oxidants: Fe2(SO4)3 and FeCl3. Resulting polymeric particles were studied thanks to SEM observations and resistivity measurements. The influence of parameters such as the ratio (monomer/oxidant), the polymerization time or the use of surfactants on the conductivity of PEDOT particles was studied. Interestingly, as-prepared PEDOT particles display conductivities between 0.1 and 10 S.cm−1 without any posttreatment. This result is nearly 1000 times higher than previously reported by Jiang et al. [1]. A first explanation can be the presence of the oxidant/surfactant combined with PEDOT particles and acting as a dopant. Besides, comparison between the samples allows us to highlight the impact of the monomer-oxidant ratio on the electrical conductivity of the pellets. To better understand these results, correlations between (i) the polymerization process, (ii) the particles morphology and (iii) final electrical properties are currently being investigated. [ABSTRACT FROM AUTHOR]

The following paper focuses on designing an innovative method for connecting 3D printed components. This is an important topic to weakness the problem of printer dimensions. The idea of connecting different parts in a larger one using compliant mechanism starts from a real application concerning the building of molds with dimensions beyond the desktop size for carbon fiber lamination. The goal is to maximize the mold quality without the need of excessively increase in printing time. These aspects provided an opportunity to delve into the topic of dividing 3d printed molds and the subsequent assembly, as well as disassembly for the extraction stages of the laminated part. The goal of the paper is to propose a mechanism capable of facilitating all stages of part production, from mold assembly to component extraction. In addition, the idea is to develop a mechanism that does not require the use of specific tools. [ABSTRACT FROM AUTHOR]

Copper nanoparticles (Cu NPs) have inherent optical and electronic properties and hence they find potential applications in the fields of printed electronic technologies, electronic device fabrication, sensors and conductive ink based electronic devices. Synthesis of pure Cu NPs through bottom up wet chemical route is a tough task because copper is highly prone to the surface oxidation and copper oxide is a very stable form at ambient conditions. In this work, crystalline metallic Cu NPs are synthesized in a one-step, eco-friendly route with L-ascorbic acid as both stabilizing and antioxidant agent and sodium borohydride as the reducing agent at the room temperature, without any inert atmosphere conditions. The structural properties of Cu NPs are studied using XRD, FTIR, FE-SEM etc. Optical properties of Cu NPs are probed through UV-Visible and fluorescent spectra. [ABSTRACT FROM AUTHOR]

Films of fluorinated graphene (FG) and structures containing them, deposited on flexible substrates, were investigated in this work under tensile deformations with a varying bend radius of 5 to 1 mm. The possibility of using FG films for flexible electronics has been demonstrated. A generalization of the electrical characteristics of films formed from a fluorinated graphene suspension is given. Three characteristic regions of the electrical characteristics of the FG films are revealed, which depend on the degree of fluorination and, in particular, on the particle size and surface morphology. [ABSTRACT FROM AUTHOR]

Due to its unique properties, graphene is a promising material for a wide range of applications, including for printed electronics. Suspensions of graphene and reduced graphene oxide (rGO) are in demand for creating conductive layers for 2D and 3D printing. Currently, technologies for the preparation of suspensions and inks from these materials are being actively developed. In this paper we consider a rather simple method for obtaining suspensions of oxidized graphene for 2D printing using a dispersant and analyzing the comparison of the structural and electrophysical characteristics of the obtained samples with samples in obtained using ultrasound. [ABSTRACT FROM AUTHOR]

We investigated the thermal conduction performance of thermal interface materials (TIM) using silver paste (SP) and silver nanoparticles (AgNPs) before and after thermal cycling. We also studied the cause that could affect the thermal resistance of SP and AgNPs after thermal cycling. The experimental data show that SP and AgNPs are good candidates for the TIM with low thermal resistance used for power electronics applications. [ABSTRACT FROM PUBLISHER]

Copper nanoparticles are alternative for silver and gold nanoparticles which are currently used in inkjet printing of conductive patterns because of the low price and high electrical conductivity. However, the serious impediment to using copper nanoparticles for conductive inks is their spontaneous oxidation. In the paper, the well-dispersed antioxidative copper pastes were prepared by dispersing the nanoparticles in an ethanol solution of lactic acid, and then deposited on glass slides. The resistivity of conductive copper films was 1.4×10−5 Ω·cm after annealing at 200 °C for 30 min. It was experimentally proved that lactic acid could react with the copper oxides surrounding Cu to form copper carboxylate, which was then reduced to Cu after annealing at 200 °C under nitrogen atmosphere. Furthermore, the copper film after annealing at 200 °C for 30 min under nitrogen atmosphere showed antioxidative characteristic. [ABSTRACT FROM PUBLISHER]

The work aims to assess the conductivity of Silver tracks printed using a state-of-the-art PixDro LP50 inkjet printer which has the capability to print conductive tracks with width as low as 50µm. The conductivity of tracks with different dimensions is measured using a Keithley measurement setup. The equivalent resistivity depends on the material, printing technology and geometrical dimensions. Profile measurements indicate a track thickness of around 300nm. The optimal printing resolution appears to be 450dpi, ensuring conductivity for all selected track widths from 50µm to 400µm. This paper analyses the influence of the layout on the electrical properties with a focus on determining the minimum metal quantity necessary to have tracks with good conductivity. [ABSTRACT FROM PUBLISHER]