scholarly journals New novel thermal insulation and sound-absorbing materials from discarded facemasks of COVID-19 pandemic

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
M. Ali ◽  
R. Almuzaiqer ◽  
K. Al-Salem ◽  
A. Alabdulkarem ◽  
A. Nuhait
Keyword(s):  
Thermal Insulation ◽  
Sound Absorption ◽  
Thermo Gravimetric Analysis ◽  
Bending Test ◽  
Gravimetric Analysis ◽  
Flexural Stress ◽  
Three Point Bending ◽  
New Novel ◽  
Absorbing Materials ◽  
Biological Contaminants

AbstractDue to the COVID-19 pandemic, people were encouraged and sometimes required to wear disposable facemasks, which then are discarded creating an environmental problem. In this study, we aim at investigating novel ideas to recycle wasted facemasks in order to lower the environmental impact. An experimental study has been carried out to investigate the possibility of using discarded masks for thermal insulation and sound absorption. The wasted masks are simulated by new masks, which stripped off the nose clips, elastic ear loops and are heated to 120 °C for one hour to kill any biological contaminants. The masks are also melted to investigate their thermal insulation and sound absorption properties. Results show that the thermal conductivity coefficients of the loose and melted masks are 0.03555 and 0.08683 W/m K, respectively, at room temperature of about 25 °C. Results show also that the sound absorption coefficient for loose masks is above 0.6 for the frequency range 600–5000 Hz. The loose facemasks are found to be thermally stable up to 295 °C, elastic ear loops at 304.7 °C, and the composite (melted) facemasks at 330.0 °C using the thermo-gravimetric analysis. Characterization of the facemask’s three-layer fibers and the composite (melted) samples is obtained using scanning electron microscopy (SEM). The three-point bending test is obtained for the composite specimens showing good values of flexural stress, flexural strain, and flexural elastic modulus. These results are promising about using such discarded masks as new thermal insulation and sound-absorbing materials for buildings replacing the synthetic or petrochemical insulation materials.

PHYSICOCHEMICAL CHANGES OF HYBRID POLYURETHANE INORGANIC THERMAL INSULATION WHEN HEATING IN AIR AND IN AN INERT ATMOSPHERE

2021 ◽  
Vol 4 ◽  
pp. 22-29
Author(s):  
Kobelev A. ◽  
◽  
Naganovsky Yu. ◽  
Kruglov E. ◽  
Aseeva R. ◽  
...  
Keyword(s):  
Thermal Insulation ◽  
Fire Hazard ◽  
Thermo Gravimetric Analysis ◽  
Inert Atmosphere ◽  
Atmospheric Environment ◽  
Gravimetric Analysis ◽  
Insulation Material ◽  
Physicochemical Changes ◽  
Fourier Spectrometry ◽  
Hybrid Polyurethane

Purpose. The article presents the results of a study of physicochemical processes occurring when a hybrid polyurethane inorganic thermal insulation is heated under dynamic conditions up to 800 °C in different atmospheric environments. The object of the study was an industrial sample of thermal insulation “FoamTech 1 550” made in South Korea. Methods. In the course of the work thermo-gravimetric analysis and IR-Fourier spectrometry were used. Samples for spectrometric analysis were prepared in the process of thermogravimetric tests by suspending the experiment. Findings. As the result of the combined studying hybrid thermal insulation material by thermogravimetry and IR-Fourier spectrometry methods, the following was established: – polyisocyanate used for obtaining the material is aliphatic in nature; – the hybrid thermal insulation sample contains about 40 % inorganics, presumably aerogel silica; – there are three main stages of hybrid thermal insulation decomposition, both in air and in an inert atmosphere; – analysis of the changes in IR spectra when heating the hybrid sample showed that at the first stage of decomposition, regardless of the atmospheric environment, the condensation reaction of silanol groups of silica aerogel takes place with the water release; – at the second stage, thickening of the inorganic framework continues, chemical polyurethane bonds with the inorganic are destroyed, and polyurethane component carbonization begins. Research application field. The results give the idea of material decomposition process in a fire. Differences in behavior in oxidizing and inert environments are shown. This is important for comparing a new group of materials with the already known types of polymer thermal insulation in terms of their fire hazard and possible application in building construction. Conclusions. The paper studies the chemical structure and physicochemical changes when heating the new group of materials, namely hybrid organic-inorganic thermal insulation materials. The article is a continuation of a team of authors’ systematic study of a thermal behavior of modern types of polymer thermal insulation.

Experimental Investigation of Kevlar KM2Plus Nano-Reinforced Laminated Composite Thermo-Mechanical Properties

2016 ◽  
Author(s):  
Abdel-Hamid I. Mourad ◽  
Omar G. Ayad ◽  
Ashfakur Rahman ◽  
Ali Hilal-Alnaqbi ◽  
Basim I. Abu-Jdayil
Keyword(s):  
Mechanical Properties ◽  
Thermo Gravimetric Analysis ◽  
Laminated Composite ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Thermo Gravimetric ◽  
Three Point Bending ◽  
Multi Walled Carbon Nanotube ◽  
Thermal Stability Of

This work is concerned with the synthesis and characterization of Multi-Walled Carbon Nanotube (MWCNT) reinforced Kevlar KM2Plus composites with various MWCNT contents (0.2, 0.3, 0.4, 0.5, 0.6, and 0.8 wt. %), by the wet lay-up technique. These samples were experimentally investigated for their thermo-mechanical properties using Thermo-Gravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), tensile testing and three-point bending techniques. The mechanical properties showed remarkable improvement with increasing MWCNT wt.% up to certain content. The results revealed that the addition of MWCNT fillers has no significant effect on the thermal stability of the composites.

scholarly journals Thermal and Mechanical Characterization of Copolymer Structure with Gradient Foam Using Additive Manufacturing and CO2 Foaming

2019 ◽  
Author(s):  
Byung Kyu Park ◽  
Charn-Jung Kim ◽  
Dong Eui Kwon ◽  
Youn-Woo Lee
Keyword(s):  
Mechanical Strength ◽  
Thermal Insulation ◽  
Thermo Gravimetric Analysis ◽  
Measurement Data ◽  
Functional Materials ◽  
Functionally Graded ◽  
Gravimetric Analysis ◽  
Polyethylene Naphthalate ◽  
Data Set ◽  
Foaming Temperature

Synthetic polymer-based gradient foams have considered as promising category of functionally graded materials with unique properties. In this study, the carbon dioxide (CO2) foaming technology has used for PET-PEN (Polyethylene Terephthalate - Polyethylene Naphthalate) copolymer towards porous functional materials with thermal insulation with reasonable mechanical strength. Through scanning electron microscope based morphological characterization, a potential to fabricate gradient foam structures with micro-pores has identified. It has shown that variation of post-foaming temperature can tune the pore size distribution although the very high post-foaming temperature tends to cause structural instability. Thermal measurement data set the limits of operation, confirmed by simultaneous differential scanning calorimeter and thermo-gravimetric analysis. Mechanical stress and thermal conductivity also has measured to find rationale of thermal insulation with reasonable mechanical strength and to elucidate the actual 3D grid foam of copolymer.

Three-Point Bending Test Behaviour of a QFN Semiconductor Package

2010 ◽  
Vol 97-101 ◽  
pp. 7-10
Author(s):  
Shahrum Abdullah ◽  
Mohd Faridz Mod Yunoh ◽  
Azman Jalar
Keyword(s):  
Applied Load ◽  
Test Bench ◽  
Maximum Load ◽  
Bending Test ◽  
Stress And Strain ◽  
Maximum Deflection ◽  
Flexural Stress ◽  
Micromechanical Property ◽  
Three Point Bending ◽  
Future Work

This paper discusses some issues in micromechanical property of a newly developed Quad Flat No-lead (QFN) 3D stacked die package using three-point bending test approach. The relevant test methodologies were carried out in order to observe the flexural stress, strain, maximum load and deflection of the package. While performing the test, these QFN packages were positioned on the three points test bench, and the specific applied load was then applied and moved down until the package was clearly bent and broken. The related findings indicated that the maximum load was found to be at 251.52 N and the maximum deflection was obtained at 0.41 mm. The results were important for setting related testing parameters (load, stress and strain) before applying the three point cyclic bending test on the QFN stacked die package as the future work.

Effect of Cork Loading on Mechanical and Thermal Properties of Silica-Ethylene-Propylene-Diene Monomer Composite

2012 ◽  
Vol 510-511 ◽  
pp. 277-283 ◽  
Author(s):  
J. Gul ◽  
S. Mirza
Keyword(s):  
Thermal Properties ◽  
Specific Gravity ◽  
Thermal Insulation ◽  
Thermo Gravimetric Analysis ◽  
Space Vehicles ◽  
Mechanical And Thermal Properties ◽  
Gravimetric Analysis ◽  
Ethylene Propylene ◽  
Low Temperature Flexibility ◽  
Lower Temperature

Ethylene-propylene diene ter-monomer (EPDM) filled with asbestos are widely used as thermal insulation in space vehicles because of its low specific gravity, low temperature flexibility, high ozone and oxygen resistant, superior thermal and ablation characteristics. However, asbestos has been banned worldwide because of its carcinogenic nature. This study was aimed to replace asbestos by environmental friendly and low specific gravity filler, cork in thermal insulation for space vehicles. Various batches of cork filled EPDM were obtained by compounding 0, 10, 20, 40, 50, 60, 70 and 100Phr (parts per hundred parts of rubber) of cork powder with EPDM in Two-roll-mill in presence of other necessary compounding ingredients. The resulted vulcanizates were characterized for mechanical, thermal and ablation performances. It was observed that cork loadings significantly enhanced tensile strength and hardness of EPDM. However, elongation at break of EPDM decreased with the increase of cork concentration. Moreover, no significant reduction in density of EPDM was obtained instead of compounding with lower specific gravity cork powder. Temperatures cures in Thermo-gravimetric analysis shifted to lower temperature with increasing of cork percentage in the formulation. Furthermore, char formation of the EPDM composites decreased with the increase of cork Phr in the composition which was the indication of degrading thermal stability of EPDM by cork powders. It can be concluded that on the basis of mechanical properties asbestos can be replaced by cork powder however, cork filled EPDM exhibited inferior thermal properties as compared to asbestos filled EPDM.

Discrete element method to model cracking for two layer systems

TAPPI Journal ◽  
2019 ◽  
Vol 18 (2) ◽  
pp. 101-108
Author(s):  
Daniel Varney ◽  
Douglas Bousfield
Keyword(s):  
Discrete Element Method ◽  
Flexural Modulus ◽  
Single Layer ◽  
Discrete Element ◽  
Flexural Stress ◽  
Layer System ◽  
Three Point Bending ◽  
Moving Force ◽  
Coating Layers ◽  
Element Method

Cracking at the fold is a serious issue for many grades of coated paper and coated board. Some recent work has suggested methods to minimize this problem by using two or more coating layers of different properties. A discrete element method (DEM) has been used to model deformation events for single layer coating systems such as in-plain and out-of-plain tension, three-point bending, and a novel moving force picking simulation, but nothing has been reported related to multiple coating layers. In this paper, a DEM model has been expanded to predict the three-point bending response of a two-layer system. The main factors evaluated include the use of different binder systems in each layer and the ratio of the bottom and top layer weights. As in the past, the properties of the binder and the binder concentration are input parameters. The model can predict crack formation that is a function of these two sets of factors. In addition, the model can predict the flexural modulus, the maximum flexural stress, and the strain-at-failure. The predictions are qualitatively compared with experimental results reported in the literature.

Synthesis of Smart Mesoporous Materials

2003 ◽  
Vol 775 ◽  
Author(s):  
G.V.Rama Rao ◽  
Qiang Fu ◽  
Linnea K. Ista ◽  
Huifang Xu ◽  
S. Balamurugan ◽  
...  
Keyword(s):  
Mesoporous Silica ◽  
Mesoporous Materials ◽  
Fluorescent Dyes ◽  
Thermo Gravimetric Analysis ◽  
Molecular Transport ◽  
Solute Diffusion ◽  
Gravimetric Analysis ◽  
Stimuli Responsive ◽  
Porous Network ◽  
Hybrid Mesoporous Materials

AbstractThis study details development of hybrid mesoporous materials in which molecular transport through mesopores can be precisely controlled and reversibly modulated. Mesoporous silica materials formed by surfactant templating were modified by surface initiated atom transfer radical polymerization of poly(N-isopropyl acrylamide) (PNIPAAm) a stimuli responsive polymer (SRP) within the porous network. Thermo gravimetric analysis and FTIR spectroscopy were used to confirm the presence of PNIPAAm on the silica surface. Nitrogen porosimetry, transmission electron microscopy and X-ray diffraction analyses confirmed that polymerization occurred uniformly within the porous network. Uptake and release of fluorescent dyes from the particles was monitored by spectrofluorimetry and scanning laser confocal microscopy. Results suggest that the presence of PNIPAAm, a SRP, in the porous network can be used to modulate the transport of aqueous solutes. At low temperature, (e.g., room temperature) the PNIPAAm is hydrated and extended and inhibits transport of analytes; at higher temperatures (e.g., 50°C) it is hydrophobic and is collapsed within the pore network, thus allowing solute diffusion into or out of the mesoporous silica. The transition form hydrophilic to hydrophobic state on polymer grafted mesoporous membranes was determined by contact angle measurements. This work has implications for the development of materials for the selective control of transport of molecular solutes in a variety of applications.

Coordination Compounds of Some 3d-Transition Metal Ions with N1-[4-(4-bromo-phenylsulfonyl)-benzoyl]-N4-(4-methoxyphenyl)- thiosemicarbazide

2008 ◽  
Vol 59 (7) ◽  
Author(s):  
Madalina Angelusiu ◽  
Maria Negoiu ◽  
Stefania-Felicia Barbuceanu ◽  
Tudor Rosu
Keyword(s):  
Coordination Compounds ◽  
Magnetic Moments ◽  
Thermo Gravimetric Analysis ◽  
Electronic Spectroscopy ◽  
Transition Metal Ions ◽  
Synthesis And Characterization ◽  
Gravimetric Analysis ◽  
Thermo Gravimetric ◽  
New Compounds

The paper presents the synthesis and characterization of Cu(II), Co(II), Ni(II), Cd(II), Zn(II) and Hg(II) complexes with N1-[4-(4-bromo-phenylsulfonyl)-benzoyl]-N4-(4-methoxyphenyl)-thiosemicarbazide. The new compounds were characterized by IR, EPR, electronic spectroscopy, magnetic moments, thermo-gravimetric analysis and elemental analysis.

Collagen And Carbon-Ferrous Nanoparticles Used As A Green Energy Composite Material For Energy Storage Devices

2020 ◽  
Vol 13 ◽  
Author(s):  
Inbasekaran S. ◽  
G. Thiyagarajan ◽  
Ramesh C. Panda ◽  
S. Sankar
Keyword(s):  
Composite Material ◽  
Thermo Gravimetric Analysis ◽  
Value Added ◽  
Green Energy ◽  
Nano Particles ◽  
Hydroxyl Group ◽  
Gravimetric Analysis ◽  
Circuit Testing ◽  
Battery Cell ◽  
Dc Voltage

Background:: Chrome shavings, a bioactive material, are generated from tannery as waste material. These chrome shaving can be used for the preparation of many value-added products. Objective:: One such attempt is made to use these chrome shaving wastes as a composite bio-battery to produce DC voltage, an alternate green energy source and cleaner technology. Methods:: Chrome shavings are hydrolyzed to make collagen paste and mixed with the ferrous nanoparticles of Moringa oleifera leaves and Carbon nanoparticles of Onion peels to form electrolyte paste as base. Then, the electrolyte base was added to the aluminum paste and conducting gel, and mixed well to form composite material for bio-battery. Results:: The composite material of bio-battery has been characterized using Scanning Electron Microscopy (SEM), Fourier-Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) and Thermo Gravimetric Analysis (TGA). Series and parallel circuit testing were done using Copper and Zinc electrodes or Carbon and Zinc electrodes as the battery terminals in the electrolyte paste. The surface area of these electrodes needs standardization from bench to pilot scale. The power generated, for an AA battery size, using a single bio-battery cell has produced a DC voltage of 1.5 V; current of 900 mA. Circuit testing on 1 ml of 80 well-cells connected in series has produced DC output of 18 V and 1100 mA whereas 48 V and 1500 mA were obtained from a series-parallel connection. Conclusion:: The glass transition temperature (Tg) of electrolyte of the bio-battery at 53°C indicates that, at this temperature, all the substances present in the bio-battery are well spread and contributing consistently to the electrolyte activity where Fe-C-Nano-Particles were able to form strong chemical bonds on the flanking hydroxyl group sites of the Collagen leading to reduced mobility of polymers and increase Tg. The results instigate promising trends for commercial exploitation of this composite for bio-battery production.

Sign in / Sign up

Export Citation Format

Share Document