Effect of Carbon Nanotube Loading on Electrical Properties of Electrospun Polyvinylidene Fluoride (PVDF) Fiber

Abstract Polyvinylidene fluoride (PVDF) is a high purity thermoplastic fluropolymer that use in the aircraft, electronics, and chemical industry. Carbon nanotube (CNTs) is made up of rolled up of graphite sheets, exhibits excellent chemical, thermal, mechanical properties, and large surface areas. PVDF fibers blended with CNTs were able to enhance the β-phase which contributes to piezoelectric properties. Electrospinning is the simplest and low-cost method to produce PVDF/CNT fibers by dissolving PVDF in solvent N, N-Dimethylformamide (DMF). 15wt% PVDF solution was used. CNT loading were varied at 0.0wt%, 0.35wt%, 0.80wt% and 1.00wt% with parameters of 20kV, tip-to-collector distance (TCD) 15cm and flow rate 1.0mLh-1. Scanning Electron Microscope (SEM), four-point probe and X-ray Diffraction (XRD) were used to determine the morphology and crystallinity of electrospun PVDF/CNT fibers. The SEM analysis concluded all fibers showed beaded structure due to low concentration of PVDF solution with insufficient ultrasonification and stirring, cause electrospraying and agglomeration. XRD and four-point probe analysis concluded PVDF/0.35wt%CNT showed the highest β-phase content with intense XRD peak and highest electrical conductivity. However, shift peak is observed among all fibres due to short electrospinning time leads to insufficient thickness of electrospun mat, which affects the mechanical properties of fibres and causes peak shift.

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Crystalinity Properties of Carbon Nanotube-Polyvinylidene Fluoride Composites

MRS Proceedings ◽

10.1557/proc-1134-bb08-11 ◽

2008 ◽

Vol 1134 ◽

Cited By ~ 1

Author(s):

Xiaobing Shan ◽

Pei-xuan Wu ◽

Lin Zhang ◽

Zhong-Yang Cheng

Keyword(s):

Differential Scanning Calorimetry ◽

Carbon Nanotube ◽

Acid Treatment ◽

Polyvinylidene Fluoride ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Β Phase ◽

Solution Cast ◽

Solution Cast Method

AbstractSingle-wall and multi-wall carbon nanotube blends (0 to 0.5 vol% ) with polyvinylidene fluoride (PVDF) have been prepared using solution cast method and characterized. By acid treatment, it has been observed that nanotube has been well functionalized and uniformly dispersed into the polymer. X-ray diffraction analysis coupled with differential scanning calorimetry (DSC) has revealed that carbon nanotube alters the crystallinity of PVDF and thereby enhances the β-phase in PVDF. Experimental results have demonstrated that enhancement of β-phase is a function of carbon nanotube concentration.

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Effect of Intercalation Structure of Organo-Modified Montmorillonite/Polylactic Acid on Wheat Straw Fiber/Polylactic Acid Composites

Polymers ◽

10.3390/polym10080896 ◽

2018 ◽

Vol 10 (8) ◽

pp. 896 ◽

Cited By ~ 7

Author(s):

Qiqi Fan ◽

Guangping Han ◽

Wanli Cheng ◽

Huafeng Tian ◽

Dong Wang ◽

...

Keyword(s):

Mechanical Properties ◽

Thermogravimetric Analysis ◽

Wheat Straw ◽

Polylactic Acid ◽

Low Cost ◽

Interlayer Spacing ◽

Positive Influence ◽

X Ray Diffraction ◽

Ft Ir ◽

Ir Analysis

In this work, an easy way to prepare the polylactic acid (PLA)/wheat straw fiber (WSF) composite was proposed. The method involved uses either the dopamine-treated WSF or the two-step montmorillonite (MMT)-modified WSF as the filler material. In order to achieve the dispersibility and exfoliation of MMT, it was modified by 12-aminododecanoic acid using a two-step route. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were performed to characterize the modified MMT and the coated WSF. As for the properties of PLA/WSF composites, some thermal (using Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis) and mechanical properties (flexural, tensile, and impact) were analyzed. The results showed that the dopamine was successfully coated onto the WSF. Furthermore, Na-MMT was successfully transformed to organo-montmorillonite (OMMT) and formed an exfoliated structure. In addition, a better dispersion of MMT was obtained using the two-step treatment. The interlayer spacing of modified MMT was 4.06 nm, which was 123% higher than that of the unmodified MMT. Additionally, FT-IR analysis suggested that OMMT diffused into the PLA matrix. The thermogravimetric analysis (TGA) showed that a higher thermal stability of PLA/WSF composites was obtained for the modified MMT and dopamine. The results also showed that both the dopamine treated WSF and the two-step-treated MMT exhibited a positive influence on the mechanical properties of PLA/WSF composites, especially on the tensile strength, which increased by 367% compared to the unmodified precursors. This route offers researchers a potential scheme to improve the thermal and mechanical properties of PLA/WSF composites in a low-cost way.

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Preparation and Chemical Protective Clothing Application of PVDF Based Sodium Sulfonate Membrane

Membranes ◽

10.3390/membranes10080190 ◽

2020 ◽

Vol 10 (8) ◽

pp. 190

Author(s):

Yue Zhao ◽

Xinbo Wang ◽

Deyin Wang ◽

Heguo Li ◽

Lei Li ◽

...

Keyword(s):

Mechanical Properties ◽

Polyvinylidene Fluoride ◽

Protective Clothing ◽

Low Cost ◽

Chemical Warfare Agents ◽

Contact Angles ◽

Protective Material ◽

Sodium Sulfonate ◽

Vapor Permeation ◽

Chemical Protective Clothing

Chemical protective clothing (CPC) is major equipment to protect human skin from hazardous chemical warfare agents (CWAs), especially nerve agents and blister agents. CPC performance is mainly dominated by the chemical protective material, which needs to meet various requirements, such as mechanical robustness, protective properties, physiological comfort, cost-effectiveness, and dimensional stability. In this study, polyvinylidene fluoride (PVDF) based sodium sulfonate membranes with different ion exchange capacities (IECs) are prepared simply from low-cost materials. Their mechanical properties, contact angles, permeations, and selectivities have been tested and compared with each other. Results show that membranes with IEC in the range of 1.5–2 mmol g−1 have high selectivities of water vapor permeation over CWA simulant vapor permeation and good mechanical properties. Therefore, PVDF-based sodium sulfonate membranes are potential materials for CPC applications.

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Effects of Cooling Rate and Sn Addition on the Microstructure of Ti-Nb-Sn Alloys

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.172-174.190 ◽

2011 ◽

Vol 172-174 ◽

pp. 190-195 ◽

Cited By ~ 8

Author(s):

Giorgia T. Aleixo ◽

Eder S.N. Lopes ◽

Rodrigo Contieri ◽

Alessandra Cremasco ◽

Conrado Ramos Moreira Afonso ◽

...

Keyword(s):

Mechanical Properties ◽

Cooling Rate ◽

Melting Furnace ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Β Phase ◽

Arc Melting ◽

Ti Alloys ◽

Ω Phase

Ti-based alloys present unique properties and hence, are employed in several industrial segments. Among Ti alloys, β type alloys form one of the most versatile classes of materials in relation to processing, microstructure and mechanical properties. It is well known that heat treatment of Ti alloys plays an important role in determining their microstructure and mechanical behavior. The aim of this work is to analyze microstructure and phases formed during cooling of β Ti-Nb-Sn alloy through different cooling rates. Initially, samples of Ti-Nb-Sn system were prepared through arc melting furnace. After, they were subjected to continuous cooling experiments to evaluate conditions for obtaining metastable phases. Microstructure analysis, differential scanning calorimetry and X-ray diffraction were performed in order to evaluate phase transformations. Depending on the cooling rate and composition, α” martensite, ω phase and β phase were obtained. Elastic modulus has been found to decrease as the amount of Sn was increased.

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Low-Cost Synthesis of Cu-Modified Immobilized Nanoporous TiO2 for Photocatalytic Degradation of 1H-Benzotriazole

Catalysts ◽

10.3390/catal10010019 ◽

2019 ◽

Vol 10 (1) ◽

pp. 19 ◽

Cited By ~ 3

Author(s):

Tihana Čižmar ◽

Ivana Panžić ◽

Krešimir Salamon ◽

Ivana Grčić ◽

Lucija Radetić ◽

...

Keyword(s):

Photocatalytic Activity ◽

Spin Coating ◽

Low Cost ◽

Electrochemical Anodization ◽

Synthesis Methods ◽

X Ray Diffraction ◽

X Ray ◽

Surface Areas ◽

Titanium Foils ◽

The Given

Cu-modified immobilized nanoporous TiO2 photocatalysts, prepared by electrochemical anodization of titanium foils, were obtained via four different synthesis methods: hydrothermal synthesis, anodization with Cu source, electrodeposition, and spin-coating, using two different copper sources, Cu(NO3)2 and Cu(acac)2. The objective of this research was to investigate how copper modifications can improve the photocatalytic activity of immobilized nanoporous TiO2 under the UV/solar light irradiation. The best photocatalytic performances were obtained for Cu-modifications using spin-coating. Therefore, the effect of irradiated catalyst surface areas on the adsorption of model pollutants, methylene blue (MB) and 1H-benzotriazole (BT), was examined for samples with Cu-modification by the spin-coating technique. The mechanisms responsible for increased degradation of MB and BT at high Cu concentrations (0.25 M and 0.5 M) and decreased degradation at low Cu loadings (0.0625 M and 0.125 M) were explained. 1H-benzotriazole was used to study the photocatalytic activity of the given samples because it is highly toxic and present in most water systems. The characterization of the synthesized Cu-modified photocatalysts in terms of phase composition, crystal structure, and morphology were investigated using X-ray Diffraction, Raman Spectroscopy, Scanning Electron Microscopy, and Energy Dispersive X-ray spectroscopy.

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Preparation and Characterization of PVA-Collagen Composite Fibers

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.236-238.83 ◽

2011 ◽

Vol 236-238 ◽

pp. 83-86 ◽

Cited By ~ 1

Author(s):

Xian Hui Sun

Keyword(s):

Mechanical Properties ◽

Sem Analysis ◽

Composite Fibers ◽

X Ray Diffraction ◽

Natural Structure ◽

Uniform Size ◽

X Ray ◽

Rheology Property ◽

Crystallization Degree

The collagen was blended with polyvinyl alcohol (PVA) with the maximum maintenance of the natural structure as precondition. The apparent viscosity and rheology property of PVA-collagen blended solution were studied. the mechanical properties of the blend membrane formed from PVA-collagen blended solution were also determined. The PVA-collagen blended solution was wet spinned with the sodium sulfate as coagulant to prepare PVA-collagen composite fibers. SEM analysis and X-ray diffraction analysis of the PVA-collagen composite fibers were studied. The results indicated that, blended with PVA, the spinning property and mechanical properties of collagen were improved. The figure of the aim fiber transect structure was similar as the kidney, and it had a uniform size. The crystallization degree of the fiber was 55.7%, and it was increased with the increase of the hot extending temperature and the extending ratio.

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Effect of fabrication technique on the crystalline phase and electrical properties of PVDF films

Materials Science-Poland ◽

10.1515/msp-2015-0020 ◽

2015 ◽

Vol 33 (1) ◽

pp. 157-162 ◽

Cited By ~ 12

Author(s):

P. K. Mahato ◽

A. Seal ◽

S. Garain ◽

S. Sen

Keyword(s):

Polyvinylidene Fluoride ◽

Tape Casting ◽

Dimethyl Formamide ◽

Pvdf Film ◽

X Ray Diffraction ◽

Β Phase ◽

Cast Films ◽

Solvent Cast ◽

Ft Ir ◽

Ferroelectric Hysteresis

AbstractThe effect of different fabrication techniques on the formation of electroactive β-phase polyvinylidene fluoride (PVDF) has been investigated. Films with varying concentration of PVDF and solvent - dimethyl formamide (DMF) were synthesized by tape casting and solvent casting techniques. The piezoelectric β-phase as well as non polar β-phase were observed for both the tape cast and solvent cast films from X-ray diffraction (XRD) micrographs and Fourier transform infra-red spectroscopy (FT-IR) spectra. A maximum percentage (80 %) of β-phase was obtained from FT-IR analysis for a solvent cast PVDF film. The surface morphology of the PVDF films was analyzed by FESEM imaging. The dielectric properties as a function of temperature and frequency and the ferroelectric hysteresis loop as a function of voltage were measured. An enhancement in the value of the dielectric constant and polarization was obtained in solvent cast films.

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Effect of AlN on Microstructure and Mechanical Properties of Mg-Al-Zn Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.704-705.1095 ◽

2011 ◽

Vol 704-705 ◽

pp. 1095-1099

Author(s):

Peng Liu ◽

Hao Ran Geng ◽

Zhen Qing Wang ◽

Jian Rong Zhu ◽

Fu Sen Pan ◽

...

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Tensile Strength ◽

Tensile Testing ◽

Cast Alloy ◽

X Ray Diffraction ◽

X Ray ◽

Β Phase ◽

Microstructure And Mechanical Properties ◽

Zn Alloy

Effects of AlN addition on the microstructure and mechanical properties of as-cast Mg-Al-Zn magnesium alloy were investigated using optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and tensile testing. Five different samples were made with different amounts of AlN(0wt%, 0.12wt%, 0.30wt%, 0.48wt%, 0. 60wt%). The results show that the phases of as-cast alloy are composed of α-Mg,β-Mg17Al12. The addition of AlN suppressed the precipitation of the β-phase. And, with the increase of AlN content, the microstructure of β-phase was changed from the reticulum to fine grains. When AlN content was up to 0.48wt% in the alloy, the β-phase became most uniform distribution. After adding 0.3wt% AlN to Al-Mg-Zn alloy, the average alloy grain size reduced from 102μm to 35μm ,the tensile strength of alloy was the highest. The average tensile strength increased from 139MPa to 169.91MPa, the hardness increased from 77.7HB to 98.4HB, but the elongation changes indistinctively. However, when more amount of AlN was added, the average alloy grain size did not reduce sequentially and increased to 50μm by adding 0.6wt% AlN and the β-phase became a little more. Keywords: Al-Mg-Zn alloy; AlN; β-Mg17Al12; Tensile strength

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Fabrication and Characterization of Alumina/Zirconia Ceramic Compound

Materials Science Forum ◽

10.4028/www.scientific.net/msf.724.249 ◽

2012 ◽

Vol 724 ◽

pp. 249-254 ◽

Cited By ~ 1

Author(s):

Bum Rae Cho ◽

Ji Hoon Chae ◽

Bo Lang Kim ◽

Jong Bong Kang

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Low Temperature ◽

Mechanical Strength ◽

Sem Analysis ◽

Zirconia Ceramic ◽

Sintering Process ◽

Sintering Aids ◽

X Ray Diffraction

Sintered ZTA(zirconia toughened alumina) which has good mechanical properties at a low temperature was produced by milling and mixing with Al2O3 and ZrO2(3Y-TZP). In order to examine the effect of sintering aids on the mechanical properties of ZTA, fracture toughness and hardness of the produced ZTA were observed in accordance with change of the added quantity of ZrO2 Scanning electron microscopy and X-ray diffraction technique were applied to observe microstructural change and phase transformation during the process. Experimental results showed that the addition of sintering aids in ZTA at a low temperature induced densification and adding SiO2 and talc lowered sintering temperature and promoted crystallization process of the compound. The mechanical strength of ZTA added ZrO2 showed higher mechanical strength and SEM analysis revealed that Al2O3 and ZrO2 during the sintering process restrained the grain growth each other. Especially, the 92% Al2O3 added sintering aids showed more than 98% of the theoretical density and more than 1500 Hv of hardness value at a low temperature of 1400. It was also showed that the fracture toughness is gradually increasing first and decreasing later in accordance with the quantity of ZrO2.

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Study on the Microstructure and Properties of Low Cost TiFeAl Alloy

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.477-478.1288 ◽

2013 ◽

Vol 477-478 ◽

pp. 1288-1292

Author(s):

Bo Long Li ◽

Tong Liu ◽

Jie Yuan ◽

Zuo Ren Nie

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Low Cost ◽

High Strength ◽

Al Alloys ◽

Vacuum Induction Melting ◽

Induction Melting ◽

Β Phase ◽

Transmission Electron ◽

Solution Strengthening

The high strength and low cost Ti-Fe based alloy was produced by double vacuum induction melting method followed by hot deformation. The microstructure has been investigated by Optical Microscopy, Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM). The microstructure of as-forged alloy is composed of α and β phase without the precipitation of TiFe intermetallic compound. The Ti-Fe-Al alloys show good comprehensive mechanical properties, demonstrating ultimate tensile strength of 1100MPa and elongation above10%. The results indicate the Fe is a good candidate for solution strengthening and simultaneously increasing ductility in titanium alloys. Effect of the Fe and Al elements on the microstructure and mechanical properties have been discussed.

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