New Inverse Emulsion-Polymerized Iron/Polyaniline Composites for Permanent, Highly Magnetic Iron Compounds via Calcination

The hydrophilic initiator potassium persulfate (KPS) was converted into a hydrophobic molecule by complexing with cetyltrimethylammonium bromide (CTAB) at both ends of the molecule (CTAPSu). Inverse emulsion polymerization thus proceeded inside micelles dispersed in the affluent toluene with CTAPSu as the initiator. Polyaniline (PANI) formed inside the micelles and entangled with Fe3O4 nanoparticles already esterified with oleic acid (OA). Iron composites consisted of OA-esterified Fe3O4 nanoparticles covered with PANI after de-emulsification. After calcination at 950 °C in an argon atmosphere, the resultant iron compound was a mixture of α-Fe (ferrite) and Fe3C (cementite), as determined by X-ray diffraction. Eventually, the calcined iron compounds (mixtures) demonstrated superparamagnetic properties with a high saturation magnetization (Ms) of 197 emu/g, which decayed to 160 emu/g after exposure to the atmosphere for four months.

Review: Sintesis Carbon Nanotubes (CNT) dari Bahan Terbarukan untuk Komposit Carbon Nanotube-Polyaniline

<p>Artikel ini berisi tentang sintesis <em>carbon nanotubes</em> (CNT) dari material tanaman sebagai upaya untuk mengurangi penggunaan bahan kimia dan pemanfaatan bahan terbarukan. CNT telah berhasil disintesis dari prekursor tanaman seperti cangkang sawit, minyak sawit, bambu, kayu karet, jerami padi, batok kelapa, serat kelapa dan minyak kelapa. Sifat unik dari CNT menyebabkan penelitiannya terus dilakukan dan banyak diterapkan dalam berbagai aplikasi salah satunya material komposit. CNT yang telah disintesis dapat dikompositkan dengan <em>polyaniline</em> (PANI) untuk memperoleh konduktivitas, sifat optik, dan kekuatan mekanik yang lebih unggul. </p><p><strong><em>Review: Synthesis of Carbon Nanotubes (CNT) from Renewable Materials for Carbon Nanotube-Polyaniline Composites. </em></strong>This article contains the synthesis of carbon nanotubes (CNT) from plant materials in an effort to reduce the use of chemicals and the use of renewable materials. CNT has been successfully synthesized from plant precursors such as palm kernel shells, palm oil, bamboo, rubberwood, rice straw, coconut shells, coconut fiber, and coconut oil. The unique properties of CNT have led to continuous research and many applications in various applications, one of which is composite materials. The synthesized CNTs can be composite with polyaniline (PANI) to obtain superior conductivity, optical properties, and mechanical strength.</p>

Printed Flexible Thermoelectric Nanocomposites Based on Carbon Nanotubes and Polyaniline

A new era of composite organic materials, nanomaterials, and printed electronics is emerging to the applications of thermoelectric generators (TEGs). Special attention is focused on carbon nanomaterials and conducting polymers, and the possibility to form pastes and inks for various low-cost deposition techniques. In this work, we present a novel approach to the processing of composite materials for screen-printing based on carbon nanotubes (CNTs) and polyaniline (PANI), supported with a dielectric polymer vehicle. Three different types of such tailor-made materials were prepared, with a functional phase consisted of carbon nanotubes and polyaniline composites fabricated with two methods: dry mixing of PANI CNT powders and in situ polymerisation of PANI with CNT. These materials were printed on flexible polymer substrates, exhibiting outstanding mechanical properties. The best parameters obtained for elaborated materials were σ=405.45 S·m−1, S=15.4 μV·K−1, and PF=85.2 nW·m−1K−2, respectively.