Effect of heat-treatment on the electrical and dielectric properties of a TiO2-containing lithia–calcia–silica glass and glass ceramics

Abdelghany

J Mater Sci: Mater Electron

2015

Infrared and optical absorption UV-Vis measurements, electrical and dielectric properties were carried out for glasses with the composition (mol%) 60B 2 O 3 Á 40BaO containing 0.0, 3, 5 and 9 g WO 3 /100 g glass. Infrared absorption spectra of all glasses indicate the presence of both triangular BO 3 units and tetrahedral BO 4 units, and the latter is overlapped with stretching vibrations of WO 4 and WO 6 units. UV-Vis measurements reveal strong charge transfer cutoff and no absorption bands were recorded in the visible region. Upon increasing WO 3 content in the studied glasses the optical band gap (E opt ) and the electrical conductivity values increase whereas activation energy values decrease. The increase in the electrical conduction was attributed to the hopping mechanism between the two sites of tungsten (W 5? , W 6? ). In the low frequency region below 1 kHz the dielectric constant measured at 200 Hz and room temperature was increased from 27 to 177 on increasing WO 3 content from 0.0 to 9.0 g WO 3 per 100 g glass, respectively. At 300°C the dielectric constant reached a value of 435 for sample containing 9.0 g WO 3 per 100 g glass. The present results may make it as a promising candidate for energy storage in electronic applications.

Section: Preparation Of Glassesmentioning

confidence: 99%

“…The dielectric constant (e 0 ), was calculated from the measured value of the capacitance [22] in the range of frequency 100 Hz-5MHz and for the temperature range from room temperature to 300°C. The variation of dielectric constant (e 0 ) as a function of frequency at different temperatures is shown in Fig.…”

Section: Dielectric Measurementsmentioning

confidence: 99%

Dielectric, electrical and spectroscopic properties of barium borates of low WO3 content

Abdelghany

J Mater Sci: Mater Electron

2015

Surface & Interface Analysis

“…Therefore, many reports have been devoted to modify bamboo fiber (BF) surface in an attempt to enhance the interfacial strength of the resulting composites, such as polymer sizing, physical coating treatment high energy irradiation and chemical grafting . Recently, chemical grafting of molecules with many active amine groups, such as poly (amido amine) (PAMAM) dendrimer, hyperbranched polyglycerol (HPG), and polyethyleneimine (PEI) onto BF surface has attracted considerable interest …”

Section: Introducionmentioning

confidence: 99%

Mechanical properties and characteristic of surface treated bamboo fiber reinforced PP/PS blends

Tang

Xiong

et al. 2018

Bamboo fiber (BF) as organic filler is characterized by mechanical properties analysis and morphology examination for polypropylene (PP) and polystyrene (PS) matrix blends. Effects of different filler content on tensile strength, flexural properties, and impact strength are proposed.It is observed from scanning electron microscopy (SEM) studies that addition of BF is beneficial in increasing mechanical strength via increasing the interface dispersed phase. The optimum tensile properties and impact properties of BF content were at 40 wt% for PP/PS/BF composite on melt mixing conditions. The results showed a significant improvement in mechanical properties of PP/PS/BF ternary blend composite. Comparing with untreated BF, content of carbon and nitrogen of treated BF decreased to 66.57 and 2.31%, oxygen content increased to 21.07%, and silicon content increased from 0 to 10.04%. The element ratio of O/C, N/C, and Si/C changed to 31.65, 3.47, and 15.08, respectively.

Surface & Interface Analysis

“…The improvement in dielectric strength for the filled epoxy resin material could be due to several factors . With increase in the surface area of particle, interfacial area leads to a significant volume fraction of polymer surrounding the particle having high interaction zone.…”

Section: Introductionmentioning

confidence: 99%

The investigation of the friction and wear properties of surface‐treated carbon fiber/SiO₂ reinforced PMMA composites

Cai

Jin

2017

The mechanical properties of SiO 2 filler particles on carbon fibers have been under discussion for several decades; the diverse models, and the properties of the components relevant to retention, are critically reviewed in the first part of this study. In addition, to gain an insight into some possible combined effect of the carbon fiber/poly(methyl methacrylate) (CF/PMMA), interfacial adhesion strength and the tensile properties and dielectric strength of the hybrid composites were studied. Simple modified rules of mixtures are used to estimate the fiber efficiency factors for the strength and modulus of the hybrid composites. Except, with the increasing fraction of CFs in PMMA, the weld line area's elongation percent is decreased. Whereas for case of SiO 2 , the 10 wt% is the threshold for micro injection molded weld line tensile strength and dielectric strength turning from decrease trend to increase. Same as CF, elongation of micro weld line samples is in general lower than neat PMMA as well, due to the addition of SiO 2 particles.