Polyaniline/V2O5 composites for anticorrosion and electromagnetic interference shielding

Polycarbonate/poly(methyl methacrylate)/silica aerogel blend composites for advanced transparent thermal insulations: Mechanical, thermal, and optical studies

Flexibility and mechanical performance are essential for transparent silicone materials applied in some optical and electronic devices; however, the tensile strength of transparent silicone materials is fairly low. To overcome this problem, a kind of UV-cured transparent flexible silicone material with quite a high tensile strength and elongation at break was developed through UV-initiated thiol-ene reaction by hyperbranched silicon-containing polymers (HBPs) with a thiol substitute and acrylate-terminated polyurethanes. Unexpectedly, it is found that both the tensile strength and elongation at break of the transparent silicone materials are extraordinarily high, which can reach 3.40 MPa and 270.0%, respectively. The UV-cured materials have good UV resistance ability because their transmittance is still as high as 93.4% (800 nm) even when aged for 40 min in a UV chamber of 10.6 mW cm-2. They exhibit outstanding adhesion to substrates, and the adhesion to a glass slide, wood, and a tin plate is grade 1. The promising results encourage us to further improve the mechanical performance of flexible transparent silicone materials by effective chemical modification strategies with HBPs. An attempt was made to apply the UV-cured materials in a Gel-Pak box and it could be proved that the UV-cured materials may be one of the good candidates for use as packaging or protecting materials of optical or electronics devices such as the Gel-Pak product.

UV-Cured Transparent Silicone Materials with High Tensile Strength Prepared from Hyperbranched Silicon-Containing Polymers and Polyurethane-Acrylates.

The progress of Industry 4.0 and the advancement of robotic design are revealing a significant gap in the capabilities of current manufacturing techniques and the selection of materials that are available in electronics. Present‐day electrical systems largely rely on metals, but there is a driving need to develop new electrically conductive objects with a wide range of material properties, including expanded flexibility and softness, and with increasingly complex geometries. Electrically conductive composites can replace traditional metal‐based systems. In particular, thermoplastic composites become electrically conductive with the incorporation of conductive fillers or polymers while retaining to a large extent the processability of the thermoplastic matrix. This is where fused filament fabrication (FFF), an additive manufacturing (AM) technique capable of processing a variety of thermoplastic‐matrix feedstock materials, can be leveraged to create electrically conductive objects with new functionalities. While there is an increasing number of publications describing the FFF of electrical objects such as sensors and circuits, there is no comprehensive review outlining the functioning mechanisms, drawbacks, and advantages of FFF as applied to conductive materials. The present review fills this lacuna by offering a critical analysis of the specific challenges and solutions to promote FFF of electrically conductive polymers and composites.

Emerging Research in Conductive Materials for Fused Filament Fabrication: A Critical Review

Single-walled carbon nanotube filled thermoplastic polyurethane nanocomposites: Influence of ionic liquid on dielectric properties

A novel multifunctional conductive blend and nanocomposites based on thermoplastic polyurethane (TPU), polyaniline (PANI) and carboxylic acid functionalized single-wall carbon nanotubes (SWCNT) with very high mechanical, thermal and excellent dielectric properties have been fabricated. The dispersion pattern and the interconnectivity of nanowire form of PANI and SWCNT in the TPU matrix are observed from HRTEM and FESEM photomicrographs. The interfacial interaction between the constituents in terms of hydrogen bonding has been confirmed from the FTIR and Raman spectra. The enhancement in tensile strength at 10 weight percentage (wt%) PANI loading explores the reinforcing nature of PANI on TPU matrix. The increase in thermal stability of the TPU/PANI blend in comparison with PANI again confirms the establishment of chemical linkages in the interface. The effect of PANI loading and temperature on the dielectric relaxation behavior has been explored in a wide range of frequency (1–106 Hz). The easiness in the polarization of the dipoles in PANI as well as in SWCNT has been confirmed from the improved value of dielectric permittivity (e′). The pronounced tunneling and hopping mode of conduction have reflected from conductivity (σac) and reduction in impedance (Z′ and Z″) value. The substantial improvement in e′ and σac of TPU/PANI/SWCNT nanocomposites at ultralow loading level of SWCNT (0.5wt %) in comparison with unfilled TPU/PANI blend is the uniqueness of this study. The effect of temperature on e′ and σac ensures the negative temperature coefficient (NTC) behavior of resistance of TPU/PANI blends.

Fabrication of thermoplastic polyurethane and polyaniline conductive blend with improved mechanical, thermal and excellent dielectric properties: exploring the effect of ultralow-level loading of SWCNT and temperature

Titanium oxide nanoparticle (TiO2)-based thermoplastic polyurethane (TPU) and highly conductive polyaniline (PANI) multifunctional nanocomposites are prepared using solvent casting technique. The interactions between the different components of the nanocomposites have been analyzed using Fourier transform infrared (FTIR) technique, and the peak obtained at 3331 cm−1, 1009 cm−1, and 667 cm−1 informs about the presence of TiO2 in the systems. The shifting of these peaks significantly explains about the interfacial interactions between the TPU, PANI, and TiO2 phases. The dispersion pattern of the of the high structured TiO2 in the interface of the heterogeneous systems has been analyzed using field emission scanning electron microscopy (FESEM) analysis and the increase in surface roughness of the cryo-fractured area explains the high extent of interfacial adhesion. The effect of TiO2 on the dielectric characteristic properties such as dielectric permittivity (e′), AC conductivity (σac), impedance (Z′ and Z″) has been explored over a wide range of frequency of applied electric filed (1 to 106 Hz) and temperature (room temperature to 100 °C). The significant enhancement in e′ and σac with increase in the incorporation of TiO2 confirms the superior dielectric characteristic properties of TiO2. The reduction in e′ with the increase in test temperature explains about the positive temperature coefficient (PTC) behavior of the developed nanocomposites. The results obtained from the analysis find the suitability of the fabricated TPU/PANI/TiO2 nanocomposites for sensor applications in various electronic sectors.

Kalyani Dash

Papers

Fabrication of thermoplastic polyurethane and polyaniline conductive blend with improved mechanical, thermal and excellent dielectric properties: exploring the effect of ultralow-level loading of SWCNT and temperature

Dielectric Relaxation Phenomena of TiO 2 Filled Polyurethane and Polyaniline Blend Nanocomposites

Electrically conductive reduced graphene oxide-based polyaniline/polyurethane blend nanocomposites with excellent dielectric properties

Enhanced dielectric properties of the ZnO nanoparticles dispersed PU/PANI blend nanocomposites