Conductive Plastic Research Articles

The Preparation of Thin Conductive Polyimide Foils for Nuclear Targets.

Thin and conductive plastic foils are of great interest to the target preparation and nuclear physics communities as a backing support for neutron-induced reaction measurements. This paper describes the preparation and characterization of thin, freestanding conductive polyimide films with an areal density suitable for target preparation in nuclear chemistry applications. The films were fabricated by blending a variety of graphene-based nanoparticles, a custom-made graphene suspension, and carbon nanotubes within a polymer matrix. The fabrication of freestanding polyimide films with an areal density of 30 μg/cm2 (∼210 nm) was both time-consuming and difficult. Here, a novel approach is described that employs a sacrificial layer and graphene material to make thin (pure and conductive) polyimide foils readily available within 24 h.

Simulation on the effect of filling porous medium on the performance of thermally conductive plastic heat sinks

High thermally conductive plastics have the characteristics of corrosion resistance, easy processing, and high thermal conductivity and can be used in corrosive environments or complex-shaped heat sinks. However, its thermal conductivity is still significantly lower than that of traditional metal heat sinks. Therefore, it is necessary to optimize the heat dissipation performance design. Based on the N–S equation and the k-ε turbulence model, the effect of porous media filled in the thermally conductive plastic heat sinks on its heat dissipation performance is studied. We compared this optimizing method with adding vortex generators in the literature. The maximum temperature of the heat sink bottom decreases by 9.3 °C. The pressure drop reduces by 55 %, and the Nusselt number increases by 9.3 %. The optimized heat sink has a hydrothermal performance factor (HTPF) 1.41. The heat dissipation performance can be similar to that of an aluminum heat sink. This study provides optimization ideas for expanding the application of thermally conductive plastics in heat sinks.

Application and Parameter Optimization of Electro-Kinetic Geosynthetics Electrodes Based on the Wild Horse Optimizer in Horizontal Electric Field Sludge Dewatering

This study systematically compared the performance of five corrosion-resistant electrode materials for electro-dewatering. Through a comprehensive analysis of dewatering efficiency, energy consumption, and corrosion resistance, conductive plastic composite electrodes (EKG) were selected as the optimal electrode material for experimentation. Additionally, the impact of electric field strength and electrode spacing on the efficiency and energy consumption of electro-dewatering (EDW) was investigated. The results showed that the increase in electric field intensity could improve the solid content and dewatering efficiency of the sediments, but the corresponding energy consumption also increased. The increased spacing of the plates reduced the dehydration effect and increased the energy consumption. By employing the Wild Horse Optimization algorithm, empirical and multifactorial response models for the dewatering solidification process were established, aimed at predicting the dewatering performance and energy consumption. The study concludes that for the remediation of heavy metals, the electric field strength should not exceed 10 V/cm to avoid excessive heavy metal migration and potential adverse chemical reactions.

Particle removal performance of a novel ESP type air cleaning system for indoor air quality in a subway station

A novel electrostatic precipitation type air cleaning technology with near zero ozone emission for indoor air quality of a subway station was developed. To minimize ozone emission and achieve high particle removal performance against ultrafine particulate matters (PMs), a multi-channel charging method using soft ionization by micrometre carbon fibers and a narrow gap collection method using high electric field by thin conductive plastic sheets as a high voltage electrode were used. In this study, the novel electrostatic charging and collection technologies were applied to a real scale air cleaning system in an Air Handling Unit (AHU) with air flow rate of 950 m3/min in Yuseong Oncheon subway station with an area of 3000 m2 in Daejeon, South Korea. The particle removal performance of the demonstration system was evaluated with real suspended particles in the subway station during test period with high PM concentrations in Korea over 40 μg/m3. Particle collection efficiency, pressure drop and ozone emission were evaluated, and compared to those of the a minimum efficiency reporting value (MERV) 10 and 14 filters used in the typical subway stations in Korea. In the field researches, the developed ESP achieved over 80% of the PM collection efficiency higher than those of the filters with MERV-10 and -14, and even 10% higher efficiency against PM1.0, while generating only 10% of pressure drop and also emitting nearly zero ozone. It is concluded that a novel ESP type air cleaning system with near zero ozone emission could be a promising air cleaning method for a large indoor environment such as a subway station where polluted air with ultrafine particles flowed in with a very high flow rate.

Mouldable Conductive Plastic with Optimised Mechanical Properties.

This paper investigates making an injection mouldable conductive plastic formulation that aims for conductivity into the electromagnetic interference (EMI) shielding range, with good mechanical properties (i.e., stiffness, strength, and impact resistance). While conductivity in the range (electrostatic charge dissipation) and EMI shielding have been attained by incorporating conductive fillers such as carbon black, metals powders, and new materials, such as carbon nanotubes (CNTs), this often occurs with a drop in tensile strength, elongation-to-break resistance, and impact resistance. It is most often the case that the incorporation of high modulus fillers leads to an increase in modulus but a drop in strength and impact resistance. In this work, we have used short carbon fibres as the conductive filler and selected a 50/50 PBT/rPET (recycled PET) for the plastic matrix. Carbon fibres are cheaper than CNTs and graphenes. The PBT/rPET has low melt viscosity and crystallises sufficiently fast during injection moulding. To improve impact resistance, a styrene-ethylene-butadiene-styrene (SEBS) rubber toughening agent was added to the plastic. The PBT/rPET had very low-impact resistance and the SEBS provided rubber toughening to it; however, the rubber caused a drop in the tensile modulus and strength. The short carbon fibre restored the modulus and strength, which reached higher value than the PBT/rPET while providing the conductivity. Scanning electron microscope pictures showed quite good bonding of the current filler (CF) to the PBT/rPET. An injection mouldable conductive plastic with high conductivity and raised modulus, strength, and impact resistance could be made.

Enhanced reduction of nitrate by TDER packed with surface-modified plastic particles electrodes

Based on Iron cathodes, nitrate could be selectively decomposed into other lower-valence nitrogen compounds, including ammonia, nitrogen gas, nitrite and nitric oxide, but the removal efficiencies of nitrate and total nitrogen (TN), are affected significantly by the synergistic effects of anodes, chloride electrolyte and conductive plastic particles electrodes. In this work, the base material Titanium (Ti) metal plates and plastic particles which surfaces were mainly coated with Ru-Sn oxidizing compounds, were applied as plates anodes and conductive particles electrodes in Three Dimensional Electrode Reactors (TDER). The Ti/RuSn plate anodes showed excellent performance on degrading nitrate, more nitrogen gas (83.84%) and less ammonia (15.51%) was produced, less TN and Iron ion (0.02 mg/L) was left in the wastewater, and less amount of chemical sludge (0.20 g/L) was produced. Furthermore, the removal efficiencies of nitrate and TN were further increased by the surface-modified plastic particles, which were cheap, reusable, corrosion-resistance, easy to obtain as manufactured materials and light to be suspended in waters. The degradation of nitrate and its intermediates was enhanced possibly by the continuous synergistic reactions initiated by hydrogen radicals, which was generated on the countless surficial active Ru-Sn sites of Ti/RuSn metal plate anodes and plastic particles electrodes, among residual nitrogen intermediates, most of ammonia was selectively converted to gaseous nitrogen by hypochlorite from chloride ion reaction.

Lightweight, bacteriostatic and thermally conductive wood plastic composite prepared by chitosan modified biointerfaces

Widely used plastic products are usually buried or directly discharged into the natural environment after use due to their difficulty in degradation, which will bring lasting harm to the fragile ecological environment. To solve the energy shortage and plastic pollution, wood plastic composite (WPC) has a great development prospect in contemporary society. However, the problem of interfacial compatibility between wood fibre and plastic leads to defects in WPC performance. This paper aims to use chitosan as an interfacial compatibiliser to modify traditional WPC, thereby greatly improving its mechanical strength, endowing it with new functions of thermal conductivity and antibacterial properties, and exploring the optimal ratio of chitosan. The prepared WPC with chitosan (CS) content of 10% (WPC-10%CS) has the best performance, including good tensile strength (99.4 MPa) and flexural strength (79.6 MPa), high water resistance (water absorption only 1.86%) and corrosion resistance, excellent UV resistance and thermal stability. WPC-10%CS also shows high thermal conductivity (up to 1.21 W/mK) and antibacterial properties. In view of all these excellent properties, WPC-10%CS has the potential to become a viable candidate material on the path to sustainable development and can be widely used as a functional material in indoor and outdoor applications.

Plastics holding metallic conductivity via semi-liquid metals

The electrically conductive polymers currently used cannot be industrially processed like plastics. Here, we reported a strategy of producing a polymer composition with tin-gallium semi-liquid alloy for plastic molding to produce conductive plastic parts with metallic conductivity (>106 S m−1). Molecular modeling and rheological experiments demonstrated that the key to successful processing was the viscosity matching between polymers and semi-liquid metals to achieve a bicontinuous structure. Our approach shows promise for the conventional industrial processing of polymer materials, such as those used for injection molding, film stretching, and fiber spinning.

Design recommendation for thermal conductive plastic parts in automotive industry

In this paper we will present a mechanical study made on the design of thermal conductive plastic parts. Out of our study derived new design rules that are useful for mechanical design engineers that have to create parts built from this type of materials. We used Catia V6 software for modelling the parts and ANSYS Moldflow software to simulate the behaviour of real components. The solutions resulted from our trials are improving the quality of the parts built from thermal conductive plastics. The test and simulation results lead us to new rules for designing screw domes and rivets for thermal conductive plastic parts and reducing warpage effect with 75% on this kind of parts.

Cooling solutions by matching plastic and metal in automotive industry

In this paper it is presented a mechanical study made on prototype parts created from aluminium and thermal conductive plastic. The scope is to replace full metal parts used for cooling electronic control unit in automotive industry and save costs. We used aluminium plates and thermal conductive plastic parts for this study. The permanent bonding of two materials, without any glue or additional additives, can be obtained by applying heat on an aluminium plate until around 300 degrees Celsius and pressing the plate on a thermal conductive plastic part. This solution has the following advantages: it can be used to cool local spots and bring around 30% savings by replacing full aluminium housings with parts built from plastic and local aluminium plates. Where the heat dissipation cannot be made without forced air convection, a solution is to combine plastic housing with an aluminium heat sink. The assembly solution is innovative. Our tests prove the efficiency of this solution to be around 20% lower than a full aluminium housing, from cooling effect point of view.

Passivation of perovskite layer surface states with pyridine in flexible and printed perovskite solar cells

Perovskite solar cells (PSCs), prepared by using solution-processed printing techniques, gained much attention over the past few years and a considerable progress has been achieved in improving the power conversion efficiencies of these devices. Nevertheless, there are still some advancements that can be implemented, especially in terms of passivation of surface defects in the perovskite photoactive layer. Passivation can afford considerable reduction in surface recombination of charge carriers in the photoactive layer and help to obtain devices with better performance. In this work, poly(3-hexylthiophene-2,5-diyl)-based inks with small amount of pyridine as an additive are used to deposit the hole transport layer and simultaneously passivate the surface defects of the perovskite layer in flexible and printed PSCs. The devices are fabricated on flexible conductive plastic substrates using a slot-die coating method. It is found that 2.5 wt.% pyridine-containing inks for preparing hole transport layer have a positive effect on the performance of resulting PSCs. On average, around 13% improvement in the power conversion efficiency is observed for the devices with passivation as opposed to the reference devices without passivation. The effect of pyridine passivation on the structural and electronic properties of the perovskite layer on a flexible substrate is studied using experimental and analytical techniques, whereas the computer simulation methods are employed to rule out the possible mechanisms for the performance improvements in the devices with passivation. The approach presented here can be useful for developing simplified protocols for printing of flexible PSCs with the passivated perovskite layer and improved device efficiency.

Characterization and optimization of a rapid, automated 3D-printed cone spray ionization-mass spectrometry (3D-PCSI-MS) methodology

3D-printed cone spray ionization-mass spectrometry (3D-PCSI-MS) is an ambient ionization technique developed for the rapid, in-situ analysis of bulk solids and trace analytes within solid matrices. A reproducibly fabricated 3D-printed cone is used as the collection device, the extraction chamber, and the spray-based ionization source. Herein, we discuss the material selection based on the extraction and spray solvent compatibility with conductive plastic types, the strength of the selected material, and the advantages and disadvantages of the cone geometry. The ease of printing and the required parameters for reproducible manufacturing is also documented. To allow for improved sample throughput, reproducible positioning, and automated solvent delivery and analysis, an autosampler was developed from commercial-off-the-shelf (COTS) parts and custom 3D-printed pieces. Finally, the application of this automated sampling via 3D-PCSI-MS on a field portable mass spectrometer was demonstrated for environmental, defense, and forensic applications.

Gel Electrophoresis Chip Using Joule Heat Self-Dissipation, Short Run Time, and Online Dynamic Imaging.

Gel electrophoresis (GE) is one of the most general tools in biomedicine. However, it suffers from low resolution, and its mechanism has not been fully revealed yet. Herein, we presented the dispersion model of w2 (t) ∝ Tt, showing the band dispersion (w) via temperature (T) and running time (t) control. Second, we designed an efficient GE chip via the time control and rapid Joule heat self-dissipation by thermal conductive plastic (TCP) and electrode buffer. Third, we conducted the simulations on TCP and polymethylmethacrylate (PMMA) chips, unveiling that (i) the temperature of TCP was lower than the PMMA one, (ii) the temperature uniformity of TCP was better than the PMMA one, and (iii) the resolution of TCP was superior to the PMMA one. Fourth, we designed both TCP and PMMA chips for experimentally validating the dispersion model, TCP chip, and simulations. Finally, we applied the TCP chip to thalassemia and model urine protein assays. The TCP chip has merits of high resolution, rapid run of 6-10 min, and low cost. This work paves the way for greatly improving electrophoretic techniques in gel, chip, and capillary via temperature and time control for biologic study, biopharma quality control, clinical diagnosis, and so on.

Thermal, Electrical, and Sensing Properties of Recycled HDPE/Carbonaceous Industrial Waste Composites

AbstractThis work is an endeavor to contemplate a value‐added conductive plastic composite material derived as recycled plastic depending on polyethylene (PE)/carbon black (CB). We choose to add CB as a filler material to enhance the electrical conductivity as well as other properties associated with the composite. The solution mixing method is adopted to develop this composite where the consequences of CB loadings on various parameters like processability, morphology, and thermal stability of the composites are examined. The perceived better filler–matrix interaction and filler dispersion observed in the scanning electron microscopy (SEM) is the underlying reason behind the improved properties. The thermal conductivity of high‐density polyethylene (HDPE) with 90 wt% CB is 2.25 W mK−1. Electrical conductivity increases with the increasing amount of the CB loading. The electrical conductivity of 60 wt% CB is 1 × 10−5 S cm−1. Electrical, thermal, and dielectric studies of the prepared plastic composite material will be studied.

Surface Enhanced Infrared Absorption Studies of SiO2–TiO2–Ag Nanofibers: Effect of Silver Electrodeposition Time on the Amplification of Signals

Surface Enhanced on Infrared Absorption (SEIRAS) and Raman Spectroscopy (SERS) are nondestructive analytic techniques used to detect low concentrations and recognize the fingerprints of molecules. The recognition of the absorption from samples by conventional infrared spectroscopy (IR) via Attenuated Total Reflection (ATR) is difficult for molecules with a low signal strength. However, developed structures with SERS and SEIRAS effect present problems such as high cost, low stability, and low compatibility. Research into new media to obtain greater amplification is largely based on the creation of nanoscale structures with symmetrical arrangements and reproducible distances, resulting in aggregates of nanoparticles that help generate hot spots which are active for amplification. The sol-gel and electrospinning method for the obtention of ceramics provides an alternative means by which to produce said substrates. Fibers of nanometric scale provide an increase of surface area which allows more contact to occur with analytes. Consequently, in this study, a silica-titania-silver nanostructured support that amplifies signal intensity for Raman and infrared spectroscopy was developed. The silica-titania support was developed by sol-gel and electrospinning techniques, and the as spun fibers were treated at 800 °C. Then, the ceramic fibrous membrane was placed on conductive indium tin oxide plastic to be doped with silver using an electroplating technique, varying the silver nitrate concentration (5, 10 and 20 mM), as well as electrodeposition times (1, 2, 5 and 10 min), with a constant voltage (1 V). Twelve different supports were obtained that showed amplification. The enhancement of infrared signals from pyridine and crystal violet molecules adsorbed on silica-titania-silver (SiO2–TiO2–Ag) nanofibers was studied in situ by Attenuated Total Reflection-Fourier Transformed Infrared Spectroscopy (ATR-FTIR). The highest amplification was obtained by the support doped at 10 min in a 10 mM concentration, with an amplification factor of 2.74 in the band localized at 3301 cm−1. In Raman spectroscopy, the highest amplification factor was 27.03, on the support doped for 5 min at a concentration of 5 mM.

Electroplating coatings on complex profiled models made of conductive and current-conducting plastic

The possibilities of the conductive and nonconductive composite plastics to be used for the complex profiled models made by the 3D prototyping in galvanoplastics are studied. A dissipating ability of the electrolyte by current and by metal using a Mohler slot cell was studied and applied, a visual study of samples was performed, and the weight and thickness of the metal deposited at different parts of the complex profiled surface of the samples was determined both of conductive and nonconductive plastics. The structure of the conductive plastic must ensure the uniformity of the electrical resistance of the material. The weight and size features of the models made of the conductive plastics for electroplating are determined. The optimal parameters of the process of electrochemical formation of the galvanoplastic copper deposits from copper sulfate electrolyte are defined. The advantages and disadvantages of the use of the conductive and nonconductive models are revealed resulting from a comparative analysis. The features of the process of galvanic coatings’ formation are determined for both cases. It is shown that, in the process of the galvanic manufacturing of the products, it is necessary to take into account a high adhesion of the deposited metal to the surface of the models made of the conductive plastic.

Carbon black enhanced wood-plastic composites for high-performance electromagnetic interference shielding

Conductive wood plastic composites (WPCs) take advantages of high mechanical strength, stability, low density and conductivity, are promising candidates as functional electromagnetic shielding materials. Thus, conductive SS-PE-CBx composites were prepared using agricultural sorghum straw residues (SS), high-density polyethylene (HDPE) and carbon black (CB) nanoparticles. With the help of rigid and conductive CB nanoparticles, SS-PE-CBx composites displayed enhanced mechanical properties, thermal stability and conductivity (0.4 S/cm), showed high EMI shielding capabilities (a maximum total EMI value of ~ 22.5 dB), which were favorable for practical applications. This work may pave a new and green way to recycle agriculture wastes into functional EMI shielding materials.

Comprehensive Analysis of a Cu Nitride Passivated Surface That Enhances Cu-to-Cu Bonding

As 3-D packaging is expected to meet new requirements for next-generation system-in-packaging (SiP), various technologies have been discussed for vertical integration. To enable high-performance vertical interconnects, Cu-to-Cu bonding is an essential process for decreasing the metal-interconnect size between vertically stacked devices and for improving system performance. However, the high-temperature and high-pressure conditions of the Cu bonding process and copper surface oxidation are important issues to be resolved for better mass production, especially for chip-to-wafer bonding. In this study, a comprehensive analysis was performed on the effects of a two-step Ar and N2 plasma treatment used to create a copper nitride passivated surface. Chemical and structural analyses of the copper nitride surface showed that this two-step plasma treatment removed nonuniformly formed native copper oxides and formed an ultrathin copper nitride passivation layer. Electrical and mechanical analyses showed that the resulting uniform conductive copper nitride surface and plastic property have the potential to improve the quality of thermocompression bonding. The results of these comprehensive analyses demonstrate the excellent ability of copper nitride to passivate copper surfaces and indicate the possibility of achieving effective Cu bonding in air.

Al, Fe and Cu waste metallic particles in conductive polystyrene composites

ABSTRACT The potential reuse of different waste metallic particulates (aluminium, iron fillings and copper) from industrial operations in the development of conductive plastic composites was considered in this study. Polystyrene based resin was obtained from waste polystyrene by solvolysis and used for developing the composite. The density, voidage fraction, electrical conductivity and microstructure of the composites were evaluated. The conductivity and the density of composites increased with filler concentration with the aluminium based composites being the most conductive. The conductive ranges of composites with aluminium, iron fillings and copper were 7.6 × 10−8 to 7.3 × 10−7, 2.1 × 10−7 to 6.0 × 10−7 and 4.6 × 10−8 to 2.5 × 10−7 S/cm respectively which suggested that they can all be used as electrostatic dissipative materials. Microstructural analysis revealed that the particles were more homogeneously dispersed in the aluminium-polystyrene composite than the others. The conductive composite produced possess moderate electrical properties suitable for various industrial and electronic applications.

Preparation and Characterization of Conductive Plastics Using Cassava Peel Waste and Addition of CuSO4

This study investigated the characteristics of a conductive plastic based on root starch and CuSO4 filler. The mixture variation was (95:5)%; (90:10)%; (85:15)%; (80:20)% and (75:25)%. Glycerol is used to change the material as desired (plasticizer) which is called a plasticizer. The method used in the manufacture of this material is melt intercalation. Mechanical testing includes tensile strength (tensile strength) and elongation at break. Thermal testing was done using DTA (Differential Thermal Analysis) and material conductivity testing. The characterization results showed that the optimum starch composition: CuSO4 (75:25)% had a conductivity value of 7.3 x 10-2S.m-1, a thermal test value of 410ºC. The optimum tensile strength value occurs in the composition (80:20)% with a value of 4.606 MPa