Materials Sciences and Applications

Journal Information
ISSN / EISSN : 2153117X / 21531188
Current Publisher: Scientific Research Publishing, Inc, (10.4236)
Total articles ≅ 1,055
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Latest articles in this journal

Mika Vähä-Nissi, Panu Lahtinen, Emmi Nuutinen, Timo Kaljunen, Tiina Pöhler
Materials Sciences and Applications, Volume 11, pp 27-43; doi:10.4236/msa.2020.111003

Abstract:The purpose was to test the feasibility of preparing cast films directly from an aqueous suspension of alkaline pretreated and fine milled chicken feathers, and to evaluate the impact of different additives on film formation and the tensile properties of the resulting films. The feather suspension consisted of stiff and sharp-pointed fibers together with more round-shaped fines. Films cast from this suspension were opaque and porous. While films without additives were fragile with drying-induced defects, film formation was improved with additives, especially with ethanolamine and maleic acid at 20% and 30% concentrations. A synergistic plasticizing effect was observed with ethanolamine and formamide, and strength of the films was improved with sodium alginate. However, the overall impact of additives on the tensile properties in general and strain at break in specific was limited. This was likely due to the dominating role of the porous film structure and the stiff fibers with a limited reactivity towards the additives.
Takashi Kawabata, Yusuke Takahashi, Yasumitsu Matsuo
Materials Sciences and Applications, Volume 11, pp 1-11; doi:10.4236/msa.2020.111001

Abstract:In order to investigate a key factor for the appearance of proton conductivity in chitin-chitosan mixed compounds, the chitin-chitosan mixed compounds (chitin)x(chitosan)1-x were prepared and these proton conductivities have been investigated. DC proton conductivity σ is obtained from Nyquist plot of impedance measurement data, and the relationship between σ and mixing ratio x has been made clear. It was found that the x dependence of σ is non-monotonous. That is, σ shows the anomalous behavior, and has peaks around x = 0.4 and 0.75. This result indicates that there exist optimal conditions for the realization of high-proton conductivity in the chitin-chitosan mixed compound in which the number of acetyl groups is different. From the FT-IR measurement, we have found that the behavior of proton conductivity in (chitin)x(chitosan)1-x is determined by the amount of water content changed by x. Using these results, proton conductivity, which is important for the application of conducting polymers in chitin-chitosan mixed compounds, will be able to be easily controlled by adjusting the mixing ratio x.
Harekrushna Sutar, Birupakshya Mishra, Rabiranjan Murmu, Sangram Patra, Sarat Chandra Patra, Subash Chandra Mishra, Debashis Roy
Materials Sciences and Applications, Volume 11, pp 12-26; doi:10.4236/msa.2020.111002

Abstract:The present experimental work reveals the surface characteristics like wettability, thermal and sliding wear behaviour of plasma-sprayed red mud (RM) coatings premixed with fly ash (FA). Varying weight % of FA (10, 20, 30 and 40)—RM composite powder is used as precursor for coating. Atmospheric plasma-sprayed coatings are developed at different operating power like 5 kW, 10 kW, 15 kW and 20 kW separately on mild steel substrate. Tribological behaviour viz. sliding wear properties are studied at distinct operating load (10N, 15N, 20N, 25N), speed (40 rpm, 50 rpm, 60 rpm, 70 rpm) and track diameter of 100 mm using a pin on disc tribometer for duration of 30 minutes with 3 minute gap period for each experiment. The DSC and TGA experiments of the coatings are performed to understand the high temperature application areas. The contact angle result signifies the wettability of the prepared coatings is principally a function of composition. The reaction of surface roughness and spraying power is in-significant on water contact angle (WCA). In conclusion, the sliding wear experiments are optimized by Taguchi method to ascertain the influencing parameter on wear.
Erika M. Inácio, Diego H. S. Souza, Marcos L. Dias
Materials Sciences and Applications, Volume 11, pp 44-57; doi:10.4236/msa.2020.111004

Abstract:PLLA-modified cellulose nanocrystals (CNC) were produced from commercial CNC by tin-catalyzed polymerization of lactide in presence of CNC. FTIR spectroscopy demonstrated that the result of the reaction produced the grafting of PLLA chains onto CNC surface (CNC-g-PLLA). Films of poly(lactic acid) (PLA) and PLA/CNC nanocomposites (with non-modified CNC and CNC-g-PLLA) containing 0.5% and 5% (w/w) of the nanofillers were prepared by casting in chloroform solution and the crystallization behavior and thermal properties investigated. All nano-composites had similar thermal stability when analyzed by TGA analyses under an inert nitrogen atmosphere. Addition of both types of CNC influenced crystallization, the higher crystallization rate being observed for 5% (w/w) CNC. Nanocomposites with 5% (w/w) CNC-g-PLLA had the strain resistance of PLA improved in the rubbery state. PLLA-modification of CNC surface increased the crystallization of PLA in PLA/CNC nanocomposites and improved the rigidity at temperatures above the glass transition, properties which are desirable for hot drinking application.
Itaru Ikeda, Noriyuki Tanaka, Motoki Kuratani, Yutaka Yamada, Osamu Sakurada
Materials Sciences and Applications, Volume 11, pp 70-80; doi:10.4236/msa.2020.111006

Abstract:Corrosion has been reported to occur in the copper tubes of heat ex-changers in multiple-circulation hot water supply systems. We have been investigating the applicability of high-strength Cu-0.65 mass% Sn-0.014 mass% Zr-0.020 mass% P alloy to counteract this corrosion. Immersion tests, electrochemical measurements, and field tests were performed. Excellent corrosion resistance of the alloy was established under conditions with flowing water due to the formation of composite films containing tin. The alloy is expected to be better than copper as a corrosion-resistant material for heat exchanger tubes.
Antônio Jedson Caldeira Brant, Natália Naime, Ademar Benévolo Lugão, Patrícia Ponce
Materials Sciences and Applications, Volume 11, pp 81-133; doi:10.4236/msa.2020.111007

Abstract:The present work firstly aimed to obtain cellulose from sugarcane bagasse by using alkaline methods in pulping/delignifying and, at bleaching stages, using sodium chlorite, glacial acetic acid, and hydrogen peroxide, associated to NaOH/KOH. The process was carried out at temperatures varying from 55°C to 110°C, under magnetic stirring in various steps lasting from 2 h to 12 h. The yields of the two cellulose extracted, SCB24-Na-I and SCB24-Na-II, were 37% and 41%, respectively, from samples of ca. 15 g of the bagasse. Secondly, it is to extract nanoparticles from the obtained celluloses via acid hydrolysis (with 77% H2SO4) to lately be tested as reinforcement in biodegradable packagings. Both celluloses and their respective nanoparticles were characterized by several techniques, among them ATR-FTIR, DSC-TGA, XRD, SEM, and TEM. Despite that the yields of cellulose nanoparticles have been low, the preliminary studies of their use in biodegradable films coated on biodegradable pots were promising.
Tomoji Ohishi, Kousei Ichikawa, Satoki Isono
Materials Sciences and Applications, Volume 11, pp 58-69; doi:10.4236/msa.2020.111005

Abstract:Flexible electronics have been recently paid much attention. A flexible substrate (Organic resin film) is indispensable component for flexible devices. Though PET film is low-cost organic film, low heat-resistance of PET film limits its application as a flexible device substrate. We have developed heat-resistant PET which does not deteriorate even at 190°C heat treatment for one hour. An excimer light was irradiated onto a polysi-lazane (PHPS: perhydropolysilane)-coated film to form a dense silicon-dioxide (SiO2) layer on a PET film, and the heat-resistance property of the formed film was examined. Changes of surface state and cross-sectional structure of the formed film due to heat treatment were investigated by scanning electron microscope (SEM) and transmission electron microscope (TEM). Compared to normal PET, which is deteriorated and whitened by heat treatment of about 110°C - 120°C, the SiO2-coated PET film maintains transparency and does not deteriorate after heat treatment at 180°C - 190°C for one hour. This high heat resistance is due to a dense SiO2 film formed on the surface that prevents surface precipitation and crystallization of low-molecular-weight oligomers (which are the cause of thermal degradation of PET). It is expected that enhancing the heat resistance of PET—which has high versatility and low cost—to about 180°C to 190°C will allow SiO2-film-coated PET to be developed as a film substrate for flexible devices.
Lev Mourokh, Yan Li, Robert Gianan, Pavel Lazarev
Materials Sciences and Applications, Volume 10, pp 33-44; doi:10.4236/msa.2019.101004

Abstract:We present the feasibility study of nonlinear dielectrics for the energy storage applications. Corona deposition of electric charges to the surface of thin films of highly polarizable organic molecules (dielectrophores) shows that the electric field inside the dielectric has a highly nonlinear response. The stored energy densities are superior to the polypropylene films, measured for the comparison, and at least comparable to the current electrochemical batteries. These results make us believe that the dielectrophores-based electrostatic capacitors can revolutionize the energy storage market.
Célia Aparecida Lino Dos Santos, Zehbour Panossian
Materials Sciences and Applications, Volume 10, pp 317-327; doi:10.4236/msa.2019.104024

Marwan Faisal, Eman El-Shenawy, Mohamed A. Taha
Materials Sciences and Applications, Volume 10, pp 433-450; doi:10.4236/msa.2019.106032

Abstract:Studying the thermo-mechanical behavior of ductile iron is necessary to develop the rolling process for ductile iron sheet/strip production, thus, extending its application by replacing steel in several fields such as machine casing, constructional applications, etc. In order to predict the safe rolling conditions for producing sheets and strips, the thermo-mechanical behavior of a ductile iron alloy, with CE of 4.48, is studied by physical simulation of hot rolling process using Gleeble-3500 simulator. The test was conducted on specimens at a range of deformation temperatures from 800°C to 950°C while three different strain rates; namely 0.05, 0.1 and 0.5 s-1 were used. The results obtained, show minimum values of flow stresses at 850°C. By increasing the deformation temperature up to 900°C, the flow stresses increased to reach maximum values, beyond which the flow stress decreased again. A remarkable dynamic recrystallization is observed at the deformation temperatures of 850°C and 800°C with applied strain rates of 0.05 and 0.1 s-1. Gleeble test results are correlated with microstructure observations on samples quenched at their deformation temperatures, where the changes in structure and graphite morphology are reported. The deformation process at high temperatures namely 950°C and 900°C result in changing the graphite shape from a spheroidal-like to a saucer-like shape. However, by decreasing the deformation temperature to 850°C as well as 800°C, graphite with lamellar shape is observed. As a conclusion, ductile iron could be successfully deformed without cracking at the applied conditions.