Infrared spectral analysis of low concentration magnetoactive polymers

Prem, Nina; Sindersberger, Dirk; Monkman, Gareth J.

doi:10.1002/app.48366

Cited by 2 publications

(1 citation statement)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It can be widely used in the characterization of the type and number of surface functional groups on activated carbon. The surface chemical properties of activated carbon are mainly determined by the type and number of surface functional groups, while the functional groups on the microporous surface of activated carbon are mostly oxygen-containing functional groups, such as carboxyl, phenolic hydroxyl, carbonyl, ester, ketone, ether, etc(Nina et al 2020;Yousif Mohammed et al…”

mentioning

confidence: 99%

Preparation and Characterization of Bio-Nitrogen-Doped Activated Carbon

Zhang

Wang

et al. 2021

Preprint

View full text Add to dashboard Cite

Blood (livestock blood) is a cheap and readily available biomass material with a relatively high protein content.In this study, bio-nitrogen doped activated carbon (BN-AC) was prepared by chemical activation method with nitrogen-rich pig blood as raw material and magnesium chloride as activator.The specific surface area of BN-AC is 283.719 m2/g, and the pore volume is 0.128 cm3/g.The optimum conditions for the preparation of BN-AC were as follows: the mass impregnation ratio of activator to blood powder was 2:1, the impregnation time was 12 h, and the activation temperature was 600 ℃.The forms of biological nitrogen in activated carbon were studied by elemental analysis, Boehm titration, FTIR and XPS.The results showed that the total basicity of 0.720 mmol/g, and acidity of 0.313 mmol/g of the BN-AC.The surface of the precursor has only one Pyrrolic N, and the surface of BN-AC contains Pyridinic N, Pyrrolic N and Graphitic N, the N content of the precursor was successfully preserved.BN-AC has higher methylene blue and iodine adsorption values than ordinary activated carbon.

show abstract

mentioning

confidence: 99%

Preparation and Characterization of Bio-Nitrogen-Doped Activated Carbon

Zhang

Wang

et al. 2021

Preprint

View full text Add to dashboard Cite

show abstract

Dielectric behaviour of magnetic hybrid materials

Monkman

Sindersberger

Prem

et al. 2020

Physical Sciences Reviews

View full text Add to dashboard Cite

The objectives of this work include the analysis of electrical and magnetic properties of magneto-elastic hybrid materials with the intention of developing new techniques for sensor and actuator applications. This includes the investigation of dielectric properties at both low and high frequencies. The behaviour of capacitors whose dielectrics comprise magnetic hybrid materials is well known. Such interfacial magnetocapacitance can be varied according to magnetic content, magnetic flux density and the relative permittivity of the polymer matrix together with other dielectric content. The basic function of trapping electrical charges in polymers (electrets) is also established technology. However, the combination of magnetoactive polymers and electrets has led to the first electromagnetic device capable of adhering to almost any material, whether magnetically susceptible or not. During the course of this research, in addition to dielectrics, electrically conductive polymers based on (PDMS) matrices were developed in order to vary the electrical properties of the material in a targeted manner. In order to ensure repeatable results, this demanded new fabrication techniques hitherto unavailable. The 3D printing of silicones is far from being a mature technology and much pioneering work was necessary before extending the usual 3 d.o.f. to include orientation about and diffusion of particles in these three axes, thus leading to the concept of 6D printing. In 6D printing, the application of a magnetic field can be used during the curing process to control the particulate distribution and thus the spatial filler particle density as desired. Most of the devices (sensors and actuators) produced by such methods contain levels of carbonyl iron powder (CIP) embedded magnetic filler of up to 70 wt%. Contrary to this, a hitherto neglected research area, namely magnetoactive polymers (MAPs) having significantly lower magnetic particle concentrations (1 to 3 wt% CIP) were also investigated. With filler concentrations lower than 3 wt%, structures are formed which are completely absent at higher filler levels. CIP concentrations in the range of 1wt% demonstrate the formation of toroidal structures. Further development of coherent rings with a compact order results as filler concentrations increase towards 2 wt%. Above 3 wt% the structure eventually disintegrates to the usual random order found in traditional MAP with higher CIP content. Structured samples containing 1%–3 wt% CIP were investigated with the aid of X-ray tomography where solitary ring structures can be observed and eventually the formation of capillary doubles. Over wavelengths ranging from 1 to 25 µm, spectroscopic analysis of thin film MAP samples containing 2 wt% CIP revealed measurable magnetic-field-dependent changes in IR absorption at a wavenumber 2350 (λ = 4.255 µm). This was found to be due to the diamagnetic susceptibility of atmospheric carbon dioxide (CO2). Consequently, the first potential application for sparse matrix MAPs was found.

show abstract

Infrared spectral analysis of low concentration magnetoactive polymers

Cited by 2 publications

References 19 publications

Preparation and Characterization of Bio-Nitrogen-Doped Activated Carbon

Preparation and Characterization of Bio-Nitrogen-Doped Activated Carbon

Dielectric behaviour of magnetic hybrid materials

Contact Info

Product

Resources

About