scholarly journals Polypyrrole with Phosphor Tungsten Acid and Carbide-Derived Carbon: Change of Solvent in Electropolymerization and Linear Actuation

Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6302
Author(s):  
Chau B. Tran ◽  
Zane Zondaka ◽  
Quoc Bao Le ◽  
Bharath Kumar Velmurugan ◽  
Rudolf Kiefer
Keyword(s):  
Aqueous Electrolyte ◽  
Composite Films ◽  
Sodium Perchlorate ◽  
Mechanical Deformation ◽  
X Ray ◽  
Aqueous Solvent ◽  
Linear Actuators ◽  
Aqueous Ethylene Glycol ◽  
Carbon Change ◽  
Carbide Derived Carbon

Linear actuators based on polypyrrole (PPy) are envisaged to have only one ion that triggers the actuation direction, either at oxidation (anion-driven) or at reduction (cation-driven). PPy doped with dodecylbenzenesulfonate (PPy/DBS) is the most common applied conducting polymer having cation-driven actuation in aqueous solvent and mainly anion-driven actuation in an organic electrolyte. It is somehow desired to have an actuator that is independent of the applied solvent in the same actuation direction. In this research we made PPy/DBS with the addition of phosphorus tungsten acid, forming PPyPT films, as well with included carbide derived carbon (CDC) resulting in PPyCDC films. The solvent in electropolymerization was changed from an aqueous ethylene glycol mixture to pure EG forming PPyPT-EG and PPyCDC-EG composites. Our goal in this study was to investigate the linear actuation properties of PPy composites applying sodium perchlorate in aqueous (NaClO4-aq) and propylene carbonate (NaClO4-PC) electrolytes. Cyclic voltammetry and square potential steps in combination with electro-chemo-mechanical-deformation (ECMD) measurements of PPy composite films were performed. The PPyPT and PPyCDC had mixed ion-actuation in NaClO4-PC while in NaClO4-aq expansion at reduction (cation-driven) was observed. Those novel PPy composites electropolymerized in EG solvent showed independently which solvent applied mainly expansion at reduction (cation-driven actuator). Chronopotentiometric measurements were performed on all composites, revealing excellent specific capacitance up to 190 F g−1 for PPyCDC-EG (best capacitance retention of 90% after 1000 cycles) and 130 F g−1 for PPyPT-EG in aqueous electrolyte. The films were characterized by scanning electron microscopy (SEM), Raman, Fourier-transform infrared (FTIR) and energy dispersive X-ray spectroscopy (EDX).

Surface Spectroscopic Signatures of Mechanical Deformation in High-Density Polyethylene (HDPE)

2018 ◽  
Vol 72 (7) ◽  
pp. 1057-1068 ◽  
Author(s):  
Shawn C. Averett ◽  
Steven K. Stanley ◽  
Joshua J. Hanson ◽  
Stacey J. Smith ◽  
James E. Patterson
Keyword(s):  
High Density Polyethylene ◽  
Cold Drawing ◽  
Mechanical Deformation ◽  
Sum Frequency Generation ◽  
High Density ◽  
X Ray ◽  
Sum Frequency ◽  
Surface Normal ◽  
Methylene Groups ◽  
Spectroscopic Signatures

High-density polyethylene (HDPE) has been extensively studied, both as a model for semi-crystalline polymers and because of its own industrial utility. During cold drawing, crystalline regions of HDPE are known to break up and align with the direction of tensile load. Structural changes due to deformation should also manifest at the surface of the polymer, but until now, a detailed molecular understanding of how the surface responds to mechanical deformation has been lacking. This work establishes a precedent for using vibrational sum-frequency generation (VSFG) spectroscopy to investigate changes in the molecular-level structure of the surface of HDPE after cold drawing. X-ray diffraction (XRD) was used to confirm that the observed surface behavior corresponds to the expected bulk response. Before tensile loading, the VSFG spectra indicate that there is significant variability in the surface structure and tilt of the methylene groups away from the surface normal. After deformation, the VSFG spectroscopic signatures are notably different. These changes suggest that hydrocarbon chains at the surface of visibly necked HDPE are aligned with the direction of loading, while the associated methylene groups are oriented with the local C2 v symmetry axis roughly parallel to the surface normal. Small amounts of unaltered material are also found at the surface of necked HDPE, with the relative amount of unaltered material decreasing as the amount of deformation increases. Aspects of the nonresonant SFG response in the transition zone between necked and undeformed polymer provide additional insight into the deformation process and may provide the first indication of mechanical deformation. Nonlinear surface spectroscopy can thus be used as a noninvasive and nondestructive tool to probe the stress history of a HPDE sample in situations where X-ray techniques are not available or not applicable. Vibrational sum-frequency generation thus has great potential as a platform for material state awareness (MSA) and should be considered as part of a broader suite of tools for such applications.

scholarly journals IMPROVEMENT OF MICROMERITIC, COMPRESSIBILITY AND SOLUBILITY CHARACTERISTICS OF LINEZOLID BY CRYSTALLO-CO-AGGLOMERATION TECHNIQUE

2017 ◽  
Vol 9 (4) ◽  
pp. 47 ◽  
Author(s):  
Atul M. Kadam ◽  
Shitalkumar S. Patil
Keyword(s):  
Drug Release ◽  
Methyl Cellulose ◽  
Mechanical Deformation ◽  
Angle Of Repose ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
X Ray ◽  
Fourier Transformation Infrared Spectroscopy ◽  
Time Required ◽  
Good Flow

Objective: The purpose of current study was to improve physicochemical properties such as micrometric, compressibility and solubility of linezolid (LNZ) by preparing crystallo-co-agglomerates (CCA) in the presence of polymer for the enhancement of overall physicochemical performance.Methods: The process of agglomeration involves the use of dichloromethane (DCM) as a good solvent and chloroform as bridging liquid were used to prepare agglomerates. Agglomerates were characterised in the solid state using several techniques such as Scanning electronic microscopy(SEM), Fourier transformation infrared spectroscopy (FTIR), X-ray powder diffraction analysis (XRPD) The agglomerates obtained were evaluated for micrometric, mechanical, deformation, compressibility and drug release properties.Results: It was found that micrometric properties and dissolution characteristics of agglomerates were significantly improved than that of pure linezolid. Solubility was found to be increased than pure linezolid. The solubility of crystallo co-agglomerates was found an increase in 5 fold 3 fold and 3.7 fold for PVPK30 (0.5%), PVPK30 (0.25%) and PVPK30 (0.75%) respectively. The angle of repose for all batches was found between 22 ° to 30 °Carrs index was between 12.27±0.6 to 18.73±0.4 and Hausners ratio Near to 1, indicated good flow ability of agglomerates. The time required for drug release over a period of 60 min, is as LA1>LA2>LA3. LA3 shows fast drug release than LA1 and LA2, due to solubilization of drug due to more concentration of PVPK30 and less concentration of talc.Conclusion: Based on the above results, it was revealed that CCA of linezolid prepared with DCM and HPMC (Hydroxypropyl methyl cellulose)/PEG (Polyethylene glycol)/PVP (Polyvinylpyrrolidone) K30 exhibited improved micrometric properties, compressibility and in addition to improving solubility and dissolution rate.

Lipophilic cage ligands containing two tightly connected 1,7-dioxa-4,10-diazacyclododecane rings: synthesis and x-ray structure of a sodium perchlorate complex

1988 ◽  
Vol 53 (22) ◽  
pp. 5292-5298 ◽  
Author(s):  
Pier Lucio Anelli ◽  
Fernando Montanari ◽  
Silvio Quici ◽  
Gianfranco Ciani ◽  
Angelo Sironi
Keyword(s):  
Sodium Perchlorate ◽  
X Ray ◽  
Perchlorate Complex

INFLUENCE OF INTERFACE AND POLARIZATION ON MAGNETOELECTRIC COUPLING IN Ni-LEAD ZIRCONIUM TITANATE-Ni TRILAYERS DERIVED BY ELECTROLESS DEPOSITION

2012 ◽  
Vol 19 (03) ◽  
pp. 1250030
Author(s):  
K. BI ◽  
Y. G. WANG
Keyword(s):  
Cross Section ◽  
Electroless Deposition ◽  
Mechanical Deformation ◽  
Interface Roughness ◽  
Zirconium Titanate ◽  
Interface Conditions ◽  
Lead Zirconium Titanate ◽  
X Ray Diffraction ◽  
X Ray ◽  
Voltage Coefficient

Magnetoelectric (ME) coupling in layered structures of magnetostrictive and piezoelectric phases are mediated by mechanical deformation and depends strongly on the interface conditions. Ni -lead zirconium titanate- Ni trilayers with neither electrodes nor bonding layers have been derived by electroless deposition. The structure of the electroless deposited Ni layer was characterized by X-ray diffraction. The cross-section of the Ni/PZT layers was investigated using scanning electron microscopy. The value of ME voltage coefficient (αE,31) increases as the interface roughness increases. The maximum of αE,31 for the Ni/PZT/Ni trilayers polarized after electroless deposition is higher than that for the Ni/PZT/Ni trilayers polarized before electroless deposition. It is essential to optimize the interface and the polarization to obtain higher ME voltage coefficient.

ELECTROLYTIC DEPOSITION OF TiC PARTICLES/Ag COMPOSITE FILMS AND THEIR MECHANICAL AND ELECTRICAL PROPERTIES

2018 ◽  
Vol 25 (08) ◽  
pp. 1850121
Author(s):  
LI YUAN ◽  
XUZHENG QIAN ◽  
CHUNYAN ZENG ◽  
CHEN GAO ◽  
YUE LU
Keyword(s):  
Electrical Properties ◽  
Silver Film ◽  
Composite Films ◽  
Electrolytic Deposition ◽  
Indentation Hardness ◽  
Pure Silver ◽  
Plating Bath ◽  
X Ray ◽  
Minor Addition ◽  
Mechanical And Electrical Properties

TiC particles/Ag composite films were successfully prepared through co-electrodeposition, using the Ag plating solutions with minor addition of TiC particles, followed by heat treatment in vacuum. The X-ray diffractometer (XRD), scanning electron microscope (SEM), nanoindentation tester and four-point probes were used to characterize phase composition, morphologies, mechanical properties and electrical properties of as-fabricated films, respectively. Experimental results show that only TiC and Ag phases are identified for the TiC particles/Ag composite films. TiC particles are incorporated tightly and evenly on the surface of the composite films without obvious agglomeration. TiC particles/Ag composite films maintain good electrical conductivity. Meanwhile, compared to pure silver film without the addition of TiC particles, the indentation hardness ([Formula: see text]) of the TiC/Ag composite film electrodeposited from the plating bath containing 6[Formula: see text]g/L of TiC particles can be improved from 600 [Formula: see text] to 11,000 [Formula: see text].

Residual Stress in Sputtered Silicon Oxycarbide Thin Films

2011 ◽  
Vol 1299 ◽  
Author(s):  
Ping Du ◽  
I-Kuan Lin ◽  
Yunfei Yan ◽  
Xin Zhang
Keyword(s):  
Thin Films ◽  
Residual Stress ◽  
Elevated Temperatures ◽  
Silicon Oxide ◽  
Composite Films ◽  
Deposition Process ◽  
Silicon Oxycarbide ◽  
X Ray ◽  
Curvature Measurement ◽  
Film Substrate

ABSTRACTSilicon carbide (SiC) has received increasing attention on the integration of microelectro-mechanical system (MEMS) due to its excellent mechanical and chemical stability at elevated temperatures. However, the deposition process of SiC thin films tends to induce relative large residual stress. In this work, the relative low stress material silicon oxide was added into SiC by RF magnetron co-sputtering to form silicon oxycarbide (SiOC) composite films. The composition of the films was characterized by Energy dispersive X-ray (EDX) analysis. The Young’s modulus and hardness of the films were measured by nanoindentation technique. The influence of oxygen/carbon ratio and rapid thermal annealing (RTA) temperature on the residual stress of the composite films was investigated by film-substrate curvature measurement using the Stoney’s equation. By choosing the appropriate composition and post processing, a film with relative low residual stress could be obtained.

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