scholarly journals Manufacture of Partially Biodegradable Composite Materials Based on PLA-Tires Powder: Process and Characterization

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Carlos Rolando Rios-Soberanis ◽  
Shuchi Wakayama ◽  
Takenobo Sakai ◽  
José de los Ángeles Rodriguez-Laviada ◽  
Emilio Pérez-Pacheco
Keyword(s):  
Volume Fraction ◽  
Research Work ◽  
Fracture Mechanisms ◽  
Infrared Analysis ◽  
Biodegradable Composite ◽  
Filler Volume Fraction ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis ◽  
Izod Impact ◽  
Solid Residuals

This research work focuses on the processability and mechanical characterization of blends of polylactic acid (PLA) and tire (elastomeric part). Wasted tires used as filler in the PLA matrix were reduced by two different processes (thermal shock and pyrolysis) in order to acquire the solid residuals in powder to be characterized and compared. Elastomeric solids obtained from scraped tires were used as filler in the PLA matrix and mixed in a Brabender 60 cc mixer at different concentrations ranging from 0% to 60% of filler volume fraction. The blend was laminated, and then samples were obtained in order to undertake mechanical properties at tension and Izod impact tests. A fully detailed analysis on the solid powders by Differential Scanning Calorimeter (DSC), thermogravimetric analysis (TGA), infrared analysis (IR), and scanning electron microscopy analysis (SEM) identified them as a rich source of carbon. Blends were characterized thermally and mechanically showing a direct effect due to the tire nature (thermoset rubber) and concentration. Fracture mechanisms were also identified.

scholarly journals Impact Resistance of Epoxy Composites Reinforced with Amazon Guaruman Fiber: A Brief Report

Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2264
Author(s):  
Raphael H. M. Reis ◽  
Fabio C. Garcia Filho ◽  
Larissa F. Nunes ◽  
Veronica S. Candido ◽  
Alisson C. R. Silva ◽  
...  
Keyword(s):  
Fiber Composite ◽  
Impact Resistance ◽  
Fiber Composites ◽  
Epoxy Composites ◽  
Impact Performance ◽  
Electron Microscopy Analysis ◽  
Ballistic Properties ◽  
Microscopy Analysis ◽  
Izod Impact ◽  
The Impact

Fibers extracted from Amazonian plants that have traditionally been used by local communities to produce simple items such as ropes, nets, and rugs, are now recognized as promising composite reinforcements. This is the case for guaruman (Ischinosiphon körn) fiber, which was recently found to present potential mechanical and ballistic properties as 30 vol% reinforcement of epoxy composites. To complement these properties, Izod impact tests are now communicated in this brief report for similar composites with up to 30 vol% of guaruman fibers. A substantial increase in impact resistance, with over than 20 times the absorbed energy for the 30 vol% guaruman fiber composite, was obtained in comparison to neat epoxy. These results were statistically validated by Weibull analysis, ANOVA, and Tukey’s test. Scanning electron microscopy analysis disclosed the mechanisms responsible for the impact performance of the guaruman fiber composites.

Precipitation Behavior of High-Nitrogen Low-Nickel Austenitic Stainless Steel at Intermediate Temperature

2012 ◽  
Vol 724 ◽  
pp. 359-362
Author(s):  
De Ning Zou ◽  
Rong Liu ◽  
Jiao Li ◽  
Kun Wu ◽  
Xiao Hua Liu
Keyword(s):  
Stainless Steel ◽  
Austenitic Stainless Steel ◽  
Grain Boundaries ◽  
Volume Fraction ◽  
Intermediate Temperature ◽  
Air Cooling ◽  
Precipitation Behavior ◽  
Lower Aging Temperature ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis

The precipitation behavior of nitrides and carbides occurred in aging process for 10Cr21Mn16NiN austenitic stainless steel at intermediate temperature was investigated by use of thermodynamic calculation, metallography and electron microscopy analysis. The precipitates evolved from chain-like initiatively along grain boundaries at lower aging temperature, to that along grain boundaries and inside the grain of austenite with more content as the temperature rising gradually. When aging at 800 °C, precipitates became layered tablet shaped and the composition was ascertained the mixture of Cr2N and M23C6. At a certain temperature, the volume fraction of precipitates for the aged testing steel by air cooling was slightly higher than that by water quenching.

scholarly journals Synthesis and Characterization of Silver Nanoparticles from Ethanolic Extracts of Leaves of Annona muricata: A Green Nanobiotechnology Approach

2019 ◽  
pp. 1-18 ◽  
Author(s):  
Yahaya Gavamukulya ◽  
Esther N. Maina ◽  
Fred Wamunyokoli ◽  
Amos M. Meroka ◽  
Edwin S. Madivoli ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Silver Nanoparticles ◽  
Green Synthesis ◽  
Infrared Analysis ◽  
Annona Muricata ◽  
Medicinal Uses ◽  
X Ray ◽  
Ethanolic Extracts ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis

Introduction: The biological green synthesis of nanoparticles via nanobiotechnology processes have a significant potential to boost nanoparticles production without the use of harsh, toxic, and expensive chemicals commonly used in conventional physical and chemical processes. Annona muricata, a tropical plant belonging to family Annonaceae is one of the most used plants in folk medicine because of its many medicinal uses and therefore presents a strong candidate for use in green synthesis. Aims: The aim of this study was to optimize a method for the synthesis of Silver Nanoparticles (AgNPs) from ethanolic extracts of leaves of Annona muricata as well as to characterize the green synthesized AgNPs. Methodology: AgNPs were synthesized from Annona muricata leaves using AgNO3 solution. The AgNPs were characterized using spectroscopy and microscopy techniques. Results: The formed AgNPs had an absorption maximum at 429 nm using UV–Visible spectroscopy and were stable under different pH, temperature, and storage conditions. Fourier transform infrared analysis revealed the different functional groups responsible for the synthesis and stabilization of the AgNPs. Scanning electron microscopy analysis revealed a spherical nature of the synthesized AgNPs. Energy dispersive x-ray spectroscopy analysis showed presence of Ag, O, and Cl with Ag having the highest composition at 60%. X-Ray Diffraction and Dynamic Light Scattering revealed a crystalline nature of AgNPs with an average size of 87.36 nm and a polydispersity index of 0.16 respectively. Transmission Electron Microscopy analysis further confirmed the crystalline and spherical nature of the AgNPs. Conclusion: In this article, an efficient, eco-friendly and low-cost method for the synthesis and recovery of stable AgNPs using Annona muricata leaves ethanolic extracts as both a reducing and capping agent has been reported for the first time. The synthesized AgNPs could be promising candidates for many biomedical, clinical, engineering, and polymer applications.

scholarly journals Physical and Mechanical Characterization of Titica Vine (Heteropsis flexuosa) Incorporated Epoxy Matrix Composites

Polymers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 4079
Author(s):  
Juliana dos Santos Carneiro da Cunha ◽  
Lucio Fabio Cassiano Nascimento ◽  
Fernanda Santos da Luz ◽  
Sergio Neves Monteiro ◽  
Maurício Ferrapontoff Lemos ◽  
...  
Keyword(s):  
Sodium Carbonate ◽  
Volume Fraction ◽  
Fracture Mechanisms ◽  
Matrix Composites ◽  
Sem Images ◽  
Chemical Treatments ◽  
Impact Tests ◽  
Izod Impact ◽  
First Time

Titica vine (Heteropsis flexuosa) is a typical plant of the Amazon region commonly used for making baskets, bags, brooms and furniture, owing to its stiff fibers. In spite of its interesting properties, there is so far no reported information regarding the use of titica vine fibers (TVFs) in engineering composite materials. In this work, the TVF and its epoxy composites were for the first time physically, thermally and mechanically characterized. Additionally, the effect of two kinds of chemical treatments, one with sodium carbonate and one with calcium lignosulfonate, as well as different volume fractions, 10, 20, 30 and 40 vol%, of TVF-reinforced composites were assessed for corresponding basic properties. The thermogravimetric results of the composites reveal enhanced thermal stability for higher TVF content. In addition, the composite incorporated with 40 vol% of TVFs treated with sodium carbonate absorbed 19% more water than the composites with untreated fibers. By contrast, the calcium lignosulfonate treatment decreased water absorption by 8%. The Charpy and Izod impact tests showed that the composites, incorporated with the highest investigated volume fraction (40 vol%) of TVF, significantly increased the absorbed energy by 18% and 28%, respectively, compared to neat epoxy. ANOVA and Tukey statistical analyses displayed no direct influence of the chemical treatments on the energy absorption of the composites for either impact tests. SEM images revealed the main fracture mechanisms responsible for the performance of TVF composites.

scholarly journals The influence of (Mn) Nano - particles on mechanical, physical, and biological properties of (PMMA/PVA-Mn) Nano - composite used for denture base

2020 ◽  
Vol 11 (2) ◽  
pp. 2320-2325
Author(s):  
Mithaq R. Mohammed ◽  
Israa H. Hilal ◽  
Shurooq J. Jabbar
Keyword(s):  
Volume Fraction ◽  
Biological Properties ◽  
Nano Particles ◽  
Nano Composites ◽  
Nano Composite ◽  
Denture Base ◽  
Morphological Studies ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis ◽  
20 Nm

The (PMMA/PVA–Mn) Nano-composites films were prepared via a photopolymerization method with different percentages (0.0%, 0.1%, and 0.2%) Of Mn with (20%PVA /80%PMMA,30%PVA/70%PMMA ad 40%PVA/60% PMMA) . The structural, bacterial, and mechanical properties of Nano-composites, were studied, X-ray properties of Mn nanoparticle which studied. Scanning electron microscopy analysis was employed to evaluate the morphological and structural properties of each thin film Nanocomposite. Moreover, the effect of Streptococcus mutans antibacterial of those materials was analyzed. Results: The morphological studies represented that both non-functionalized and Bio functionalized manganese oxide NPs (MnNPs) formed are of spherical morphology but exhibited with a difference in size about 20 nm and 27-40 nm, respectively. The performance of the antimicrobial activity. The results are revealed that the Bio functionalized MoNPs showed higher antibacterial. Results show that values increase in each of Mn Nanoparticle and with different concentrations of (PVA/PMMA) polymer, then decrease alternately less value of volume fraction of fillers. Young modules values increase alternately by the volume fraction of fillers.

scholarly journals Influence of corn flour as pore forming agent on porous ceramic material based mullite: Morphology and mechanical properties

2016 ◽  
Vol 48 (1) ◽  
pp. 29-39 ◽  
Author(s):  
J.G. Ayala-Landeros ◽  
V. Saucedo-Rivalcoba ◽  
S. Bribiesca-Vasquez ◽  
V.M. Castaño ◽  
A.L. Martínez-Hernández ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Ceramic Material ◽  
Volume Fraction ◽  
Porous Ceramic ◽  
Corn Flour ◽  
Crystalline Phases ◽  
Talcum Powder ◽  
X Ray ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis

Porous material was processed by the mixing, molding and pressing the ceramic material, afterward burnout and sintering; through the forming porous, using corn flour at different concentration (10, 15 and 20 wt.%) as a pore forming agent; in order to determinate the influence of porous on the mechanical, morphological and structural properties. The effect of the volume fraction of corn flour in the mullite matrix, at various sintering temperature from 1100, 1200, 1300 and 1500?C were tested by Diffraction X ray, showing changes in crystalline phases of mullite (3Al2O3-2SiO2), as result of sintered temperatures. Presence of talcum powder in formula, also cause the formation of the cordierite and cristobalite crystalline phases, giving stability and adhesion to the structure of ceramic material. When sintering at temperatures between 1300 to 1500?C, and it was used the concentration of corn flour 15-20 wt.% as forming agent porous, it was found the better mechanical properties. The scanning electron microscopy analysis shows the presence of open porosity and anisotropy.

Material analysis techniques using the ion mill

1996 ◽  
Vol 54 ◽  
pp. 1034-1035
Author(s):  
J. P. Benedict ◽  
R. M. Anderson ◽  
S. J. Klepeis
Keyword(s):  
Polished Surface ◽  
Surface Material ◽  
Analysis Techniques ◽  
Material Analysis ◽  
Optical Inspection ◽  
Electron Microscopy Analysis ◽  
Microscopy Analysis ◽  
Argon Ions ◽  
The Impact ◽  
Scanning Electron

Ion mills equipped with flood guns can perform two important functions in material analysis; they can either remove material or deposit material. The ion mill holder shown in Fig. 1 is used to remove material from the polished surface of a sample for further optical inspection or SEM ( Scanning Electron Microscopy ) analysis. The sample is attached to a pohshing stud type SEM mount and placed in the ion mill holder with the polished surface of the sample pointing straight up, as shown in Fig 2. As the holder is rotating in the ion mill, Argon ions from the flood gun are directed down at the top of the sample. The impact of Argon ions against the surface of the sample causes some of the surface material to leave the sample at a material dependent, nonuniform rate. As a result, the polished surface will begin to develop topography during milling as fast sputtering materials leave behind depressions in the polished surface.

scholarly journals Mechanical properties, deformation and fracture mechanisms of bimodal Cu under tensile test

2021 ◽  
Vol 60 (1) ◽  
pp. 15-24
Author(s):  
Silu Liu ◽  
Yonghao Zhao
Keyword(s):  
Yield Strength ◽  
Grain Refinement ◽  
Volume Fraction ◽  
Shear Fracture ◽  
High Strength ◽  
Tensile Specimen ◽  
Deformation Mechanisms ◽  
Fracture Mechanisms ◽  
Fracture Angle ◽  
Area Reduction

Abstract Metals with a bimodal grain size distribution have been found to have both high strength and good ductility. However, the coordinated deformation mechanisms underneath the ultrafine-grains (UFGs) and coarse grains (CGs) still remain undiscovered yet. In present work, a bimodal Cu with 80% volume fraction of recrystallized micro-grains was prepared by the annealing of equal-channel angular pressing (ECAP) processed ultrafine grained Cu at 473 K for 40 min. The bimodal Cu has an optimal strength-ductility combination (yield strength of 220 MPa and ductility of 34%), a larger shear fracture angle of 83∘ and a larger area reduction of 78% compared with the as-ECAPed UFG Cu (yield strength of 410 MPa, ductility of 16%, shear fracture angle of 70∘, area reduction of 69%). Grain refinement of recrystallized micro-grains and detwinning of annealing growth twins were observed in the fractured bimodal Cu tensile specimen. The underlying deformation mechanisms for grain refinement and detwinning were analyzed and discussed.

Effects of Various Antioxidant Pretreatment Modalities on Adhesion to Sound and Caries-Affected Dentin: An In Vitro Study

2021 ◽  
pp. 232020682199798
Author(s):  
Beyza Unalan Degirmenci ◽  
Alperen Degirmenci ◽  
Emine Kara
Keyword(s):  
Bond Strength ◽  
In Vitro Study ◽  
Natural Antioxidants ◽  
Microtensile Bond Strength ◽  
Mandibular Molar ◽  
Electron Microscopy Analysis ◽  
Molar Teeth ◽  
Microscopy Analysis ◽  
Two Parameters

Aim: Natural antioxidants were offered as the answer of dentin adhesion issue. The aim of this study is to investigate the effects of proanthocyanidin and lycopene as pretreatment agents on the sound and caries-affected dentin surface on microtensile bond strength and microleakage. Materials and Methods: This study was designed as in vitro because of that 84 mandibular molar teeth were collected. Forty-two of the included teeth were carious teeth, while the other 42 were without caries. Sixty of them were used for microleakage and 24 for microtensile bond strength testing and scanning electron microscopy analysis. The samples were divided into six subgroups randomly according to dentin pretreatments: 5% proanthocyanidin, 5% lycopene, and no antioxidant application. After the restorative procedures, samples were attached to the microtensile tester. Samples were subjected to tensile stress in the load cell until they broke at a speed of 0.5 mm per min. Microtensile bond strength (µTBS) and microleakage test data were analyzed with two-way analysis of variance, Bonferroni correction, and Tamhane’s T2 tests. Results: Two-way variance analysis showed that dentin pretreatment applications, dentin substrate, and the interaction between these two parameters had statistically significant effects on µTBS values ( P < .001). There was no difference between dentin pretreatment applications in terms of microleakage scores ( P > .05). Conclusion: The application of dentin pretreatment with proanthocyanidin is a successful procedure that increases the bond strength in both dentin substrate, while pretreatment with lycopene in caries-affected dentin reduces it.

Sign in / Sign up

Export Citation Format

Share Document