scholarly journals MXene Enabling the Long-Term Superior Thermo-Oxidative Resistance for Elastomers

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 493
Author(s):  
Gui-Xiang Liu ◽  
Ya-Dong Yang ◽  
Ding Zhu ◽  
Yan-Chan Wei ◽  
Shuangquan Liao ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Free Radicals ◽  
Carbon Black ◽  
Universal Design ◽  
Design Strategy ◽  
Model Material ◽  
Oxidative Process ◽  
Oxidative Resistance ◽  
Good Guide

The ability of long-term thermo-oxidative resistance is very important for elastomers in application. However, many conventional antioxidants are difficult to realize the long-term thermo-oxidative resistance. To overcome this limitation, a design strategy is introduced by combing elastomers with MXene and natural rubber (NR) is chosen as a model material. MXene is efficient in absorbing oxygen and the generated free radicals in the NR matrix and can inhibit the diffusion of oxygen toward the interior. Moreover, MXene, like graphene and carbon black, absorbs molecular chains, inhibiting the migration of MXene toward the surface of the sample. Such characteristics of MXene endow NR/MXene with the long-term outstanding thermo-oxidative resistance. For example, after three days of the thermo-oxidative process for NR/MXene, the tensile strength is 19 MPa and the retention of tensile strength is 63%, which far exceeds the effects of conventional antioxidants. This work not only provides a good guide for the universal design of elastomers with long-term thermo-oxidative resistance but also expands the application of MXene.

scholarly journals Effect of Nucleating Additives on Short- and Long-Term Tensile Strength and Residual Stresses of Welded Polypropylene Samples

Polymers ◽  
2021 ◽  
Vol 13 (17) ◽  
pp. 2965
Author(s):  
Andrea Wübbeke ◽  
Volker Schöppner ◽  
Theresa Arndt ◽  
Jan-Ole Maras ◽  
Marcus Fitze ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Carbon Black ◽  
Residual Stresses ◽  
Weld Seam ◽  
Nucleating Agent ◽  
Hole Drilling ◽  
Nucleating Agents ◽  
Short Term ◽  
Short And Long Term

Additives such as nucleating agents are often used in the processing of plastic products not only for improving production efficiency but also for enhancing mechanical performance. In this work, the short- and long-term tensile strength, the morphology as well as the residual stresses of the welded polypropylene (PP) samples with different fillers (carbon black and special beta-nucleating agents) and different dimensionless joining paths are analyzed. Results obtained are then compared with those that are representative of the initial, filler-free samples. It is shown that, upon using the special beta-nucleating agent, superior long-term tensile strength can be achieved compared to the samples without additives or with carbon black agent (e.g., for the dimensionless joining path of 0.95, the long-term tensile strength of a PP nature sample is characterized by around 400 MPa, whereas by adding beta-nucleating agent 1% the value can be increased by 400% to reach around 2050 MPa). However, adding beta-nucleating agent 1% yields inferior short-term tensile strength. The hole drilling method (HDM) is used for the analysis of residual stresses. It is found that the residual stresses in the weld seam are characterized by low values of the tensile stresses. The residual stresses in the weld seam also can be converted from tensile into compressive stresses by adding the beta nucleating agent. However, this has the disadvantage that with a higher proportion by weight of the beta nucleating agent, the short-term tensile strength of the welded joint becomes lower than that of the other tested bonds.

Minimalistic Design Approach for Multi-Reactivity against Free Radicals and Metal-Free and Metal-Bound Amyloid-β Peptides: Redox-Based Substitutions of Benzene

2019 ◽  
Author(s):  
Mingeun Kim ◽  
Juhye Kang ◽  
Misun Lee ◽  
Jiyeon Han ◽  
Geewoo Nam ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Free Radicals ◽  
Amyloid Β ◽  
Design Strategy ◽  
Design Approach ◽  
Metal Free

We report a minimalistic redox-based design strategy for engineering compact molecules based on the simplest aromatic framework, benzene, with multi-reactivity against free radicals, metal-free amyloid-β, and metal-bound amyloid-β, implicated in the most common form of dementia, Alzheimer’s disease.

ATI 6-2-4-2

Alloy Digest ◽  
2020 ◽  
Vol 69 (8) ◽  
Keyword(s):  
Tensile Strength ◽  
Titanium Alloy ◽  
High Temperature ◽  
Creep Strength ◽  
High Strength ◽  
Heat Treating ◽  
Good Combination ◽  
Long Term Stability ◽  
Temperature Performance

Abstract ATI 6-2-4-2 is a near-alpha, high strength, titanium alloy that exhibits a good combination of tensile strength, creep strength, toughness, and long-term stability at temperatures up to 425 °C (800 °F). Silicon up to 0.1% frequently is added to improve the creep resistance of the alloy. This datasheet provides information on composition, physical properties, hardness, and tensile properties as well as creep. It also includes information on high temperature performance as well as forming, heat treating, machining, and joining. Filing Code: Ti-169. Producer or Source: ATI.

Influence of Alkalinity and Ambient Temperature on Long-Term Properties of GFRP Reinforcement

2018 ◽  
Vol 760 ◽  
pp. 213-218
Author(s):  
František Girgle ◽  
Lenka Bodnárová ◽  
Ondřej Januš ◽  
Vojtěch Kostiha
Keyword(s):  
Tensile Strength ◽  
Ambient Temperature ◽  
Mechanical Characteristics ◽  
Current Problem ◽  
Concrete Structures ◽  
Experimental Program ◽  
Glass Fibres ◽  
Metallic Reinforcement ◽  
Gfrp Reinforcement

The article deals with the current problem of determining long-term reliability of non-metallic reinforcement in concrete structures. The alkaline environment of concrete with a pH higher than 12.0 affects the glass fibres degradative, whereas this degradation presents by reduction of their mechanical characteristics, resulting in a decrease in the tensile strength of the whole composite. The article summarizes the results of the ongoing experimental program so far, which aims to quantify this influence.

Effects of Accelerated Aging Period of Time at 180°C on Tensile Property of Plain Woven Fabric/Epoxy Resin Laminated Composites

2012 ◽  
Vol 182-183 ◽  
pp. 76-79 ◽  
Author(s):  
Lei Lei Song ◽  
Quan Rong Liu ◽  
Jia Lu Li
Keyword(s):  
Tensile Strength ◽  
Carbon Fiber ◽  
Epoxy Resin ◽  
Laminated Composites ◽  
Accelerated Aging ◽  
Woven Fabric ◽  
Accelerated Ageing ◽  
Time Intervals ◽  
Composite Samples

In this paper, carbon fiber reinforced resin matrix composites were produced by stacking eight pieces of carbon fiber woven plain fabric and subjected to accelerated ageing. Accelerated ageing was carried out in oven at 180°C for three different time intervals (60 hours, 120 hours and 180 hours). The influence of different ageing time intervals at 180°C on tensile properties of laminated composites was examined, compared with the composites without aging. The appearance and damage forms of these laminated composites were investigated. The results revealed that the tensile strength of the laminates declined significantly after long term accelerated aging at 180°C. The average tensile strengths of composite samples aged 60 hours, 120 hours, and 180 hours period of time at 180°C are 80.36%, 79.82%, 76.57% of average tensile strength of composite samples without aging, respectively. The high temperature accelerated aging makes the resin macromolecular structure in the composites changed, and then the adhesive force between fiber bundles and resin declines rapidly which result in the tensile strength of composites aged decrease. This research provides a useful reference for long term durability of laminated/epoxy resin composites.

Effect of Diameter and Surface Area of Carbon Black Particles on Certain Properties of Rubber Compounds

1944 ◽  
Vol 17 (2) ◽  
pp. 451-474
Author(s):  
D. Parkinson
Keyword(s):  
Particle Size ◽  
Tensile Strength ◽  
Carbon Black ◽  
Abrasion Resistance ◽  
Particle Diameter ◽  
Stiffness Modulus ◽  
Carbon Structures ◽  
Rubber Compounds ◽  
Regular Manner ◽  
Tear Resistance

Abstract Carbon blacks can be grouped into different classes according to the way in which their fineness of division relates to different properties in rubber. Within any one class the principal properties vary in a regular manner with particle size. The normal class consists of the furnace carbons, Kosmos (Dixie)-40, Statex, the rubber-grade impingement carbons, and possibly, the color-grade impingement carbons. The subnormal classes consist of thermal carbons and acetylene and lamp blacks. Irrespective of the above classification, the properties which depend more on fineness of division than on other factors are rebound resilience, abrasion resistance, tensile strength and tear resistance. The lower limit of particle diameter for best tensile strength and tear resistance appears to be higher than that for abrasion resistance. B.S.I, hardness and electrical conductivity are properties which depend at least as much on other factors as on particle size. Stiffness (modulus) depends more on other factors than on particle size. Factors modifying the effects of particle size (or specific surface) include the presence of carbon-carbon structures and a reduction in strength of bond in rubber-carbon structures. Carbon black is thought to exist in rubber in four states: agglomerated, flocculated, dispersed, and bonded to the rubber molecules (the reënforcing fraction). Abrasion resistance is regarded as providing the only reliable measure of reënforcement.

Hyperelastic models for the description and simulation of rubber subjected to large tensile loading

2021 ◽  
Vol 2 (108) ◽  
pp. 75-85
Author(s):  
Q.H. Jebur ◽  
M.J. Jweeg ◽  
M. Al-Waily ◽  
H.Y. Ahmad ◽  
K.K. Resan
Keyword(s):  
Tensile Strength ◽  
Carbon Black ◽  
Tensile Test ◽  
Accurate Description ◽  
Percentage Error ◽  
Relative Percentage ◽  
Elastomeric Material ◽  
Tensile Data ◽  
Relative Percentage Error ◽  
Hyperelastic Models

Purpose: Rubber is widely used in tires, mechanical parts, and user goods where elasticity is necessary. Some essential features persist unsolved, primarily if they function in excessive mechanical properties. It is required to study elastomeric Rubber's performance, which is operational in high-level dynamic pressure and high tensile strength. These elastomeric aims to increase stress breaking and preserve highly pressurised tensile strength. Design/methodology/approach: The effects of carbon black polymer matrix on the tensile feature of different Rubber have been numerically investigated in this research. Rubber's material characteristics properties were measured using three different percentages (80%, 90%and 100%) of carbon black filler parts per Hundreds Rubber (pphr). Findings: This study found that the tensile strength and elongation are strengthened as the carbon black filler proportion increases by 30%. Practical implications: This research study experimental tests for Rubber within four hyperelastic models: Ogden's Model, Mooney-Rivlin Model, Neo Hooke Model, Arruda- Boyce Model obtain the parameters for the simulation of the material response using the finite element method (FEM) for comparison purposes. These four models have been extensively used in research within Rubber. The hyperelastic models have been utilised to predict the tensile test curves—the accurate description and prediction of elastomer rubber models. For four models, elastomeric material tensile data were used in the FEA package of Abaqus. The relative percentage error was calculated when predicting fitness in selecting the appropriate model—the accurate description and prediction of elastomer rubber models. For four models, elastomeric material tensile data were used in the FEA package of Abaqus. The relative percentage error was calculated when predicting fitness in selecting the appropriate model. Numerical Ogden model results have shown that the relative fitness error was the case with large strains are from 1% to 2.04%. Originality/value: In contrast, other models estimate parameters with fitting errors from 2.3% to 49.45%. The four hyperelastic models were tensile test simulations conducted to verify the efficacy of the tensile test. The results show that experimental data for the uniaxial test hyperelastic behaviour can be regenerated effectively as experiments. Ultimately, it was found that Ogden's Model demonstrates better alignment with the test data than other models.

Mechanistic Approach for Long-Term Stability of a Polyethylene Glycol–Carbon Black Nanocomposite Sensor

ACS Sensors ◽  
2021 ◽  
Author(s):  
Wenjun Li ◽  
Kazuki Nagashima ◽  
Takuro Hosomi ◽  
Chen Wang ◽  
Yosuke Hanai ◽  
...  
Keyword(s):  
Polyethylene Glycol ◽  
Carbon Black ◽  
Term Stability ◽  
Long Term Stability ◽  
Mechanistic Approach ◽  
Nanocomposite Sensor

scholarly journals Therapy with high‑dose long‑term antioxidant free radicals for severe paraquat poisoning: A pilot study

2018 ◽  
Author(s):  
Shunlin Hu ◽  
Chuanhu Qiao ◽  
Zhengli Yuan ◽  
Min� Li ◽  
Jiangfeng Ye ◽  
...  
Keyword(s):  
Free Radicals ◽  
Pilot Study ◽  
High Dose ◽  
Paraquat Poisoning
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