scholarly journals Investigation of Surface Degradation of Aged High Temperature Vulcanized (HTV) Silicone Rubber Insulators

Energies ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3769 ◽  
Author(s):  
Mohamed Ghouse Shaik ◽  
Vijayarekha Karuppaiyan
Keyword(s):  
Silicone Rubber ◽  
Degradation Mechanism ◽  
Low Cost ◽  
Polymeric Composite ◽  
Work Conditions ◽  
Contact Angles ◽  
Electrical Performance ◽  
Surface Degradation ◽  
Physicochemical Changes ◽  
Service Period

Polymeric composite insulators are subjected to varying work conditions like rain and heat, which create an impact on degradation during their long service period. Electrical tracking under the Alternating Current (AC) field plays a predominant role in surface degradation, which can be different for fresh and aged insulations. The tracking studies on the fresh and aged polymeric insulation therefore become significant. Motivated by this, an indigenous low-cost electrical tracking setup was developed, and the tracking studies were carried out as per International Electro technical Commission standard (IEC) 60587 on fresh, thermal-aged and water-aged silicone rubber samples. Contact angles of samples were measured to analyse the effect of ageing on hydrophobicity. Further, to analyse the influence of ageing on insulation integrity, tracking tests were conducted and parameters like leakage current pattern and magnitudes, tracking length and loss of weight in the material due to tracking were examined. The physicochemical impacts of ageing on the surface degradation of the samples were also analysed using X-ray diffraction analysis and Fourier Transform Infrared Spectroscopy analysis. The investigations added insight into the degradation mechanism of polymeric insulators in terms of their electrical performance and physicochemical changes in the material. Comparison of these changes showed that ageing could influence surface degradation of samples.

scholarly journals Upcycling of Vine Shoots: Production of Fillers for PHBV-Based Biocomposite Applications

2020 ◽  
Author(s):  
Grégoire David ◽  
Laurent Heux ◽  
Stéphanie Pradeau ◽  
Nathalie Gontard ◽  
Hélène Angellier-Coussy
Keyword(s):  
Water Vapor ◽  
Gas Phase ◽  
Mechanical Performance ◽  
Low Cost ◽  
Water Vapor Permeability ◽  
Contact Angles ◽  
Vapor Permeability ◽  
Water Contact ◽  
Median Diameter ◽  
Cost Of Materials

Abstract This paper aims at investigating the potential of vine shoots (ViSh) upcycling as fillers in novel poly(3-hydroxybutyrate-3-hydroxyvalerate) (PHBV) based biocomposites. ViSh particles of around 50 µm (apparent median diameter) were obtained combining dry grinding processes, and mixed with PHBV using melt extrusion. Thermal stability and elongation at break of biocomposites were reduced with increasing contents of ViSh particles (10, 20 and 30 wt%), while Young’s modulus and water vapor permeability were increased. It was shown that a surface gas-phase esterification allowed to significantly increase the hydrophobicity of ViSh particles (increase of water contact angles from 59° to 114°), leading to a reduction of 27% in the water vapor permeability of the biocomposite filled with 30 wt% of ViSh. The overall mechanical performance was not impacted by gas-phase esterification, demonstrating that the interfacial adhesion between the virgin ViSh particles and the PHBV matrix was already good and that such filler surface treatment was not required in that case. It was concluded that ViSh particles can be interestingly used as low cost fillers in PHBV-based biocomposites to decrease the overall cost of materials.

scholarly journals Lifetime Analysis of Rubber Gasket Composed of Methyl Vinyl Silicone Rubber with Low-Temperature Resistance

2015 ◽  
Vol 2015 ◽  
pp. 1-9
Author(s):  
Young-Doo Kwon ◽  
Seong-Hwa Jun ◽  
Ji-Min Song
Keyword(s):  
Silicone Rubber ◽  
Mechanical Load ◽  
Low Cost ◽  
Accelerated Life Test ◽  
Parameter Method ◽  
Ambient Conditions ◽  
Methyl Vinyl ◽  
Accelerated Life ◽  
Elastomeric Materials ◽  
Lifetime Analysis

Most machines and instruments constantly require elastomeric materials like rubber for the purposes of shock absorption, noise attenuation, and sealing. The material properties and accurate lifetime prediction of rubber are closely related to the quality of machines, especially their durability and reliability. The properties of rubber-like elastomers are influenced by ambient conditions, such as temperature, environment, and mechanical load. Moreover, the initial properties of rubber gaskets must be sustained under working conditions to satisfy their required function. Because of its technical merits, as well as its low cost, the highly accelerated life test (HALT) is used by many researchers to predict the long-term lifetime of rubber materials. Methyl vinyl silicone rubber (VMQ) has recently been adopted to improve the lifetime of automobile radiator gaskets. A four-parameter method of determining the recovery ability of the gaskets was recently published, and two revised methods of obtaining the recovery were proposed for polyacrylate (ACM) rubber. The recovery rate curves for VMQ were acquired using the successive zooming genetic algorithm (SZGA). The gasket lifetime for the target recovery (60%) of a compressed gasket was computed somewhat differently depending on the selected regression model.

Development of Bridge Tooling for Fabricating Mold Inserts of Aspheric Optical Lens

2012 ◽  
Vol 516 ◽  
pp. 228-233
Author(s):  
Chil Chyuan Kuo ◽  
Zhi Yang Lin
Keyword(s):  
Success Rate ◽  
Silicone Rubber ◽  
Low Cost ◽  
Fabrication Process ◽  
Optical Lens ◽  
Aspheric Lenses

Bridge tooling has been developed for fabricating the temporary mould inserts of aspheric lenses using silicone rubber materials. Prototype material for aspheric lenses is not recommended as quartz due to the low success rate in the fabrication process. This technology provides a fast, low cost and highly successful rate of fabricating the epoxy-based composite mould inserts of plastic aspheric optical lenses.

scholarly journals Image Analysis Determination of the Influence of Surface Structure of Silicone Rubbers on Biofouling

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Sevil Atarijabarzadeh ◽  
Fritjof Nilsson ◽  
Henrik Hillborg ◽  
Sigbritt Karlsson ◽  
Emma Strömberg
Keyword(s):  
Image Analysis ◽  
Silicone Rubber ◽  
Microbial Growth ◽  
Plane Surface ◽  
Contact Angle Hysteresis ◽  
Contact Angles ◽  
Homogeneous Distribution ◽  
Textured Surface ◽  
Textured Surfaces ◽  
Band Formation

This study focuses on how the texture of the silicone rubber material affects the distribution of microbial growth on the surface of materials used for high voltage insulation. The analysis of surface wetting properties showed that the textured surfaces provide higher receding contact angles and therefore lower contact angle hysteresis. The textured surfaces decrease the risk for dry band formation and thus preserve the electrical properties of the material due to a more homogeneous distribution of water on the surface, which, however, promotes the formation of more extensive biofilms. The samples were inoculated with fungal suspension and incubated in a microenvironment chamber simulating authentic conditions in the field. The extent and distribution of microbial growth on the textured and plane surface samples representing the different parts of the insulator housing that is shank and shed were determined by visual inspection and image analysis methods. The results showed that the microbial growth was evenly distributed on the surface of the textured samples but restricted to limited areas on the plane samples. More intensive microbial growth was determined on the textured samples representing sheds. It would therefore be preferable to use the textured surface silicone rubber for the shank of the insulator.

scholarly journals Design of a low-cost laser CUT-OFF filters using carmine dye-doped PVA polymeric composite films

2020 ◽  
Vol 18 ◽  
pp. 103203 ◽  
Author(s):  
Z.A. Alrowaili ◽  
Mohammed Ezzeldien ◽  
M.I. Mohammed ◽  
I.S. Yahia
Keyword(s):  
Low Cost ◽  
Composite Films ◽  
Polymeric Composite

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

Membranes ◽  
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.

Surface degradation mechanism of InP/InGaAs APDs

1988 ◽  
Vol 6 (10) ◽  
pp. 1496-1501 ◽  
Author(s):  
H. Sudo ◽  
M. Suzuki
Keyword(s):  
Degradation Mechanism ◽  
Surface Degradation

PLA conductive filament for 3D printed smart sensing applications

2018 ◽  
Vol 24 (4) ◽  
pp. 739-743 ◽  
Author(s):  
Simone Luigi Marasso ◽  
Matteo Cocuzza ◽  
Valentina Bertana ◽  
Francesco Perrucci ◽  
Alessio Tommasi ◽  
...  
Keyword(s):  
Temperature Sensor ◽  
Low Cost ◽  
Conductive Polymer ◽  
Temperature Characteristic ◽  
Temperature Sensors ◽  
Electrical Performance ◽  
Content Type ◽  
Sensing Applications ◽  
3D Printed

Purpose This paper aims to present a study on a commercial conductive polylactic acid (PLA) filament and its potential application in a three-dimensional (3D) printed smart cap embedding a resistive temperature sensor made of this material. The final aim of this study is to add a fundamental block to the electrical characterization of printed conductive polymers, which are promising to mimic the electrical performance of metals and semiconductors. The studied PLA filament demonstrates not only to be suitable for a simple 3D printed concept but also to show peculiar characteristics that can be exploited to fabricate freeform low-cost temperature sensors. Design/methodology/approach The first part is focused on the conductive properties of the PLA filament and its temperature dependency. After obtaining a resistance temperature characteristic of this material, the same was used to fabricate a part of a 3D printed smart cap. Findings An approach to the characterization of the 3D printed conductive polymer has been presented. The major results are related to the definition of resistance vs temperature characteristic of the material. This model was then exploited to design a temperature sensor embedded in a 3D printed smart cap. Practical implications This study demonstrates that commercial conductive PLA filaments can be suitable materials for 3D printed low-cost temperature sensors or constitutive parts of a 3D printed smart object. Originality/value The paper clearly demonstrates that a new generation of 3D printed smart objects can already be obtained using low-cost commercial materials.

A TXV-less Packaging Platform for the Era of IoTs

2015 ◽  
Vol 2015 (1) ◽  
pp. 1-5 ◽  
Author(s):  
Dyi-Chung Hu ◽  
Yu-Min Lin ◽  
Hsiang Hung Chang ◽  
Tao-Chih Chang ◽  
Wei-Chung Lo ◽  
...  
Keyword(s):  
Low Cost ◽  
High Density ◽  
The Other ◽  
Electrical Performance ◽  
Test Vehicle ◽  
Technology Infrastructure ◽  
Fine Line ◽  
Large Panel ◽  
Line Technology ◽  
Test Chips

A new concept of packaging platform calls eHDF (embedded high density film), that without any TXVs is been proposed. The eHDF uses the technology from two categories; one utilize the semiconductor fine line technology infrastructure and the other takes the advantage of laminate organic large panel process infrastructure. Hence, the fine line, better electrical performance and low cost requirements can be addressed at the same time by the eHDF packaging platform. In this paper, a test vehicle based on eHDF structure will be built and modules assembly with test chips on eHDF substrate will be performed.

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