Browse
Submit Data
Databases
API
Help

Dataset Information

24 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Novel Polyimide/Copper-Nickel Ferrite Composites with Tunable Magnetic and Dielectric Properties.

ABSTRACT: Heat-resistant magnetic polymer composites were prepared by incorporating cerium-doped copper-nickel ferrite particles, having the general formula Ni_1-xCu_xFe_1.92Ce_0.08O₄ (x: 0.0, 0.3, 0.6, 1.0), into a polyimide matrix. The effects of particle type and concentration on the thermal, magnetic, and electrical properties of the resulting composites were investigated. The samples were characterized by FTIR, scanning electron microscopy, X-ray diffractometry, thermogravimetric analysis, differential scanning calorimetry, vibrating sample magnetometer, and broadband dielectric spectroscopy. The composites exhibited high thermal stability, having initial decomposition temperatures between 495 and 509 °C. Saturation magnetization (M_s), magnetic remanence (M_r), and coercivity (H_c) were found in range of 2.37-10.90 emu g^-1, 0.45-2.84 emu g^-1, and 32-244 Oe, respectively. The study of dielectric properties revealed dielectric constant values of 3.0-4.3 and low dielectric losses of 0.016-0.197 at room temperature and a frequency of 1 Hz.

SUBMITTER: Hamciuc C

PROVIDER: S-EPMC8158717 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Tunable heat generation in nickel-substituted zinc ferrite nanoparticles for magnetic hyperthermia.

Project description:We report a high-performance magnetic nanoparticle as a hyperthermic agent under low applied field and frequency. CTAB (cetyltrimethylammonium bromide)-coated Ni x Zn1-x Fe2O4 nanoparticles of average particle size < 25 nm with various stoichiometric ratios were successfully synthesized using a co-precipitation technique. Characterization results indicate a close interaction of CTAB ions with the surface metal ions resulting in a cation distribution deviating from their equilibrium positions. Magnetic measurements were done at 300 K and 5 K using a superconducting quantum interference device. Saturation magnetization gradually increases with increasing substitution of Ni2+ ions with Zn2+ ions, attributed to the cation distribution and high super-exchange interaction between the A- and B-sites. The average size of the nanoparticles is estimated to be <10 nm with a magnetically dead layer (>1 nm @ 300 K), reflecting the effect of CTAB coating on the surface of the nanoparticles. The magnetocrystalline anisotropy (K eff), obtained from the law of approach to saturation, is inversely proportional to the M s value. The increasing incorporation of Ni2+ ions in the lattice system is found to influence various structural parameters, which is reflected in the magnetic performance of the nanoparticles. A specific absorption rate of 347 W g-1 and intrinsic loss power of 4.6 nH m2 kg-1 was attained with a minimal concentration of 2 mg ml-1 in a very short time period of 1.5 min in Ni0.75Zn0.25Fe2O4 nanoparticles.

| S-EPMC9417590 | biostudies-literature

Tunable Crystalline Phases in UV-Curable PEG-Grafted Ladder-Structured Silsesquioxane/Polyimide Composites.

Project description:A series of UV-curable hybrid composite blends containing a carboxylic acid functionalized polyimidewith varying amounts of high molecular weight (~1 K) PEG-grafted ladder-structured polysilsesquioxanes copolymerized with methacryl groups were fabricated and their structural, thermal, mechanical, and surface properties characterized. At a composite weight ratio of polyimide above 50 wt.%, a stark shift from amorphous to crystalline polyethylene glycol (PEG) phases were observed, accompanied by a drastic increase in both surface moduli and brittleness index. Moreover, fabricated composites were shown to have a wide range water contact angle, 9.8°-73.8°, attesting to the tunable surface properties of these amphiphilic hybrid polymer composites. The enhanced mechanical properties, combined with the utility of tunable surface hydrophilicity allows for the possible use of these hybrid polymer composites to be utilized as photosensitive polyimide negative photoresists for a myriad of semiconductor patterning processes.

| S-EPMC7287875 | biostudies-literature

Cobalt, nickel and copper complexes with glycinamide: structural insights and magnetic properties.

Project description:Ten new compounds of Co, Ni and Cu with glycinamide (HL = glycinamide): [Co(H2O)2(HL)2]Cl2 (1a), [Co(H2O)2(HL)2]Br1.06Cl0.94 (1b), [Co(H2O)2(HL)2]I2 (1c), [Ni(H2O)2(HL)2]Cl2 (2a), [Ni(H2O)2(HL)2]Br0.94Cl1.06 (2b), [Ni(H2O)2(HL)2]I2 (low and room temperature polymorph, 2cLT and 2cRT), [CuCl2(HL)2] (3a), [CuBr1.3Cl0.7(HL)2] (3b) and {[Cu(HL)2]2[Cu2I6]} n (3c), as well as glycinamide hydroiodide (H2LI) and a new polymorph of glycinamide hydrochloride (β-H2LCl) were prepared and characterized by single-crystal X-ray diffraction, infrared spectroscopy, thermal analysis (TG/DTA) and ESR spectroscopy. 1a, 1b, 2a and 2b are isostructural, as well as 1c and 2cRT, while the Cu compounds (3a-c) have entirely different molecular structures. All investigated compounds are mononuclear with exception of the 1D coordination polymer 3c. Compound 3c contains copper ions in the mixed oxidation state Cu(i) and Cu(ii) with interesting magnetic properties. Paramagnetic behaviour was found in 1a, 1b, 3a and 3b. Temperature induced polymorphic transformation was observed in 2c. Compounds 1a and 3a showed moderate antiproliferative activity and selectivity toward the human breast tumor cell line MCF-7.

| S-EPMC9066431 | biostudies-literature

Sonochemical Combined Synthesis of Nickel Ferrite and Cobalt Ferrite Magnetic Nanoparticles and Their Application in Glycan Analysis.

Project description:The combination of the sonochemical activation of Ni(NO3)2 and Co(NO3)2 in the presence of Fe(NO3)3 and polyethylene glycol and consecutive heat treatment of the formed metal hydroxides offers a cheap and efficient method for the preparation of nickel ferrite and cobalt ferrite magnetic nanoparticles, which can be successfully applied in the selective capture of fluorescently derivatized N-glycans from human serum. XRD measurement revealed that, besides the ferrite phase, nickel and cobalt oxides also form during heat treatment. The amount of simple metal oxides can be well controlled by the temperature of the heat treatment, since increasing temperature yielded higher spinel content. For both nickel and cobalt, the best heat treatment temperature was found to be 673 K, where the samples contained 84.1% nickel ferrite, and in the case of cobalt, almost pure (99.6%) cobalt ferrite could be prepared. FT-IR and zeta potential measurements indicated the presence of surface OH groups, which aided in the dispersion of the particles in water and, in addition, can promote the adsorption of polar compounds. The practical applicability of the magnetic nanopowders was demonstrated in the purification of fluorescently derivatized N-glycans (from human serum). Cobalt ferrite was found to be the most effective. Owing to the easy preparation and the simplicity of the magnetic separation the pure cobalt ferrite, magnetic nanoparticles could be efficient tools for the selective enrichment of serum N-glycans in HPLC measurements.

| S-EPMC9103833 | biostudies-literature

Enhanced Electromagnetic Absorption Properties of Commercial Ni/MWCNTs Composites by Adjusting Dielectric Properties.

Project description:In this manuscript, we constructed a Ni/MWCNTs absorber and properly adjusted the permittivity resulted from absorber content in the PVDF to optimize impedance matching properties. Both ε' and ε″ increase obviously with the increasing content of Ni/MWCNTs in PVDF, demonstrating that dielectric properties are dependent on the conductivity. Moderate dielectric properties and excellent impedance matching can be obtained for the filler content of 20 wt% Ni/MWCNTs. Reasonable impedance matching allows electromagnetic waves to propagate into the materials and finally realize energy dissipation through dielectric loss and interfacial polarization. As expected, the minimum reflection loss (RL) of -46.85 dB at 6.56 GHz with a low filler loading (20 wt%) and wide effective bandwidth (RL<-10 dB) of 14.0 GHz in the thickness range of 1.5-5.0 mm was obtained for the commercial Ni/MWCNTs composites, which is promising for mass production in industrial applications. Our findings offer an effective and industrialized way to design high-performance material to facilitate the research in microwave absorption.

| S-EPMC7058662 | biostudies-literature

Tuning of spinel magnesium ferrite nanoparticles with enhanced magnetic properties.

Project description:Monodispersed magnesium ferrite nanoparticles with enhanced magnetic properties were successfully fabricated by a simple solvothermal method without employing any templates, complex apparatus or techniques. The structure, morphology, composition, and magnetic properties of the products were tuned and characterized by X-ray powder diffraction, transmission electron microscopy, scanning electron microscopy and vibrating sample magnetometry. The results show that the reaction time and temperature have an important influence on the morphology, composition, structure and particle size of the synthesized MgFe2O4 nanoparticles. Not only the size, size distribution, crystallization, but also the atomic ratio of Mg : Fe has a decisive effect on their magnetic properties. The MgFe2O4 magnetic nanoparticles synthesized at 180 °C for 12 hours have excellent dispersion, narrow size distribution, good crystallinity and a Mg : Fe atomic ratio of approximately 1 : 4.53 and an average particle size of 114.3 nm, thus the highest saturation magnetization of 67.35 emu g-1. It provides a reliable synthesis method for the better application of spinel structure magnesium ferrite nanoparticles in the future.

| S-EPMC9090794 | biostudies-literature

Magnetic field tunable small-scale mechanical properties of nickel single crystals measured by nanoindentation technique.

Project description:Nano- and micromagnetic materials have been extensively employed in micro-functional devices. However, measuring small-scale mechanical and magnetomechanical properties is challenging, which restricts the design of new products and the performance of smart devices. A new magnetomechanical nanoindentation technique is developed and tested on a nickel single crystal in the absence and presence of a saturated magnetic field. Small-scale parameters such as Young's modulus, indentation hardness, and plastic index are dependent on the applied magnetic field, which differ greatly from their macroscale counterparts. Possible mechanisms that induced 31% increase in modulus and 7% reduction in hardness (i.e., the flexomagnetic effect and the interaction between dislocations and magnetic field, respectively) are analyzed and discussed. Results could be useful in the microminiaturization of applications, such as tunable mechanical resonators and magnetic field sensors.

| S-EPMC3974134 | biostudies-other

Inducing Magnetic Properties with Ferrite Nanoparticles in Resins for Additive Manufacturing.

Project description:Additive manufacturing and nanotechnology have been used as fundamental tools for the production of nanostructured parts with magnetic properties, expanding the range of applications in additive processes through tank photopolymerization. Magnetic cobalt ferrite (CoFe2O4) and barium ferrite (BaFe12O19) nanoparticles (NPs) with an average size distribution value (DTEM) of 12 ± 2.95 nm and 37 ± 12.78 nm, respectively, were generated by the hydroxide precipitation method. The dispersion of the NPs in commercial resins (Anycubic Green and IRIX White resin) was achieved through mechanochemical reactions carried out in an agate mortar for 20 min at room temperature, with limited exposure to light. The resulting product of each reaction was placed in amber vials and stored in a box to avoid light exposure. The photopolymerization process was carried out only at low concentrations (% w/w NPs/resin) since high concentrations did not result in the formation of pieces, due to the high refractive index of ferrites. The Raman spectroscopy of the final pieces showed the presence of magnetic NPs without any apparent chemical changes. The electron paramagnetic resonance (EPR) results of the pieces demonstrated that their magnetic properties were maintained and not altered during the photopolymerization. Although significant differences were observed in the dispersion process of the NPs in each piece, we determined that the photopolymerization did not affect the structure and superparamagnetic behavior of ferrite NPs during processing, successfully transferring the magnetic properties to the final 3D-printed piece.

| S-EPMC10380220 | biostudies-literature

Dielectric Properties of Hybrid Polyethylene Composites Containing Cobalt Nanoparticles and Carbon Nanotubes.

Project description:Polymer composites with electrically conductive inclusions are intensively developed for microwave shielding applications, where lightweight and elastic coatings are necessary. In this paper, dielectric properties of hybrid polyethylene composites containing cobalt nanoparticles and multi-wall carbon nanotubes (MWCNT) were investigated in the wide frequency range of 20-40 GHz for electromagnetic shielding applications. The percolation threshold in the hybrid system is close to 6.95 wt% MWCNT and 0.56 Co wt%. Cobalt nanoparticles (up to highest investigated concentration 4.8 wt%) had no impact on the percolation threshold, and for the fixed total concentration of fillers, the complex dielectric permittivity is higher for composites with bigger MWCNT concentrations. Moreover, the microwave complex dielectric permittivity of composites with high concentration of fillers is quite high (for composites with 13.4 wt% MWCNT and 1.1 wt% Co ε' ≈ ε″ ≈ 20 at 30 GHz, it corresponds to microwave absorption 50% of 1 mm thickness plate); therefore, these composites are suitable for electromagnetic shielding applications.

| S-EPMC8912063 | biostudies-literature

Simultaneously Improving the Optical, Dielectric, and Solubility Properties of Fluorene-Based Polyimide with Silyl Ether Side Groups.

Project description:Three fluorene-based polyimides with silyl ether groups (Si-PIs) were successfully synthesized by a simple and efficient silicon etherification reaction of hydroxyl-containing polyimides (OH-PIs) and tert-butylchlorodiphenylsilane (TBDPSCl), and their structures were confirmed by 1H NMR and IR spectra. The bulky nonpolar tert-butyldiphenylsilyl (TBDPS) side groups in the modified PI unit instead of the strong electron donor -OH group is conducive to decreasing electronic conjugation and charge transfer (CT) interaction along the PI chain. Accordingly, the optical, dielectric, and solubility properties of the modified Si-PI films are simultaneously improved compared with the precursor OH-PI films. The modified Si-PI films demonstrate a meaningful enhancement in the transmittances at a wavelength of 400 nm (T 400 ) to 74-81% from 42 to 55% of OH-PI films and the regeneration of fluorescence characteristics. The dielectric constant and loss of Si-PI films are also obviously reduced to 2.63-2.75 and 0.0024-0.0091 at 1 kHz from 4.19 to 4.78 and 0.0173-0.0295 of OH-PI films, respectively, due to substituted with the bulky nonpolar TBDPS groups to increase the free volume and hydrophobicity of Si-PI films. The solubility of Si-PIs in low- or nonpolar solvents (such as CHCl3, CH2Cl2, acetone, and toluene) is significantly improved. Furthermore, Si-PI films still maintain relatively good thermal properties with the 5% weight loss temperature (T 5% ) in the range 470-491 °C under a nitrogen atmosphere and the glass transition temperature (T g ) in the range 245-308 °C.

| S-EPMC9016839 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data