Artificial Weathering Mechanisms of Uncoated Structural Polyethylene Terephthalate Fabrics with Focus on Tensile Strength Degradation

In the past five decades, reinforced coated textile membranes have been used increasingly as building materials, which are environmentally exposed. Thus, their weathering degradation over the service life must be taken into account in design, fabrication, and construction. Regarding such structural membranes, PVC (polyvinylchloride)-coated PET (polyethylene terephthalate) fabric is one of the most common commercially available types. This paper focuses on the backbone of it, i.e., the woven PET fabric. Herein, weathering of uncoated PET, as the load-bearing component of the composite PET-PVC, was studied. This study assessed the uniaxial tensile strength degradation mechanisms of uncoated PET fabric during artificial accelerated weathering tests. For this purpose, exploratory data analysis was carried out to analyze the chemical and physical changes which were traced by Fourier transform infrared spectroscopy and molecular weight measurements. Finally, with the help of degradation mechanisms determined from the aforementioned evaluations, a degradation pathway network model was constructed. With that, the relationship between applied stress, mechanistic variables, structural changes, and performance level responses (tensile strength degradation) was assessed.

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Studies on Uniaxial Compressive Strength, Uniaxial Tensile Strength, Youngs Modulus, Poissons Ratio of Iron Ore in relation their Influence in Optimum Rock Blasting Process.Central Afghanistan

International Journal of Computer Sciences and Engineering ◽

10.26438/ijcse/v7i4.140151 ◽

2019 ◽

Vol 7 (4) ◽

pp. 140-151

Author(s):

Fatima Rezaye ◽

Shivanna .

Keyword(s):

Tensile Strength ◽

Compressive Strength ◽

Uniaxial Compressive Strength ◽

Iron Ore ◽

Uniaxial Tensile ◽

Rock Blasting ◽

Uniaxial Tensile Strength ◽

Poissons Ratio

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Enhanced Method of Predicting Tensile Strength Degradation of Steel Bridge Members Due to Corrosion

Recent Patents on Corrosion Science ◽

10.2174/1877610811202010030 ◽

2012 ◽

Vol 2 (1) ◽

pp. 30-41

Author(s):

J. M.R.S. Appuhamy ◽

M. Ohga ◽

T. Kaita ◽

P. Chun ◽

P. B.R. Dissanayake

Keyword(s):

Tensile Strength ◽

Strength Degradation ◽

Steel Bridge

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Influence of spin finish on degradation, functionalization and long-term storage of polyethylene terephthalate fabrics dedicated to ligament prostheses

Scientific Reports ◽

10.1038/s41598-021-83572-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Tuan Ngoc Nguyen ◽

Andre Rangel ◽

David W. Grainger ◽

Véronique Migonney

Keyword(s):

Young’S Modulus ◽

Polyethylene Terephthalate ◽

Uv Light ◽

Young's Modulus ◽

Cruciate Ligament ◽

Surface Cleaning ◽

Anionic Polymer ◽

Pet Fabric ◽

Oil Storage ◽

Grafting Degree

AbstractPolyethylene terephthalate (PET) fibers and fabrics are widely used for medical device applications such as vascular and anterior cruciate ligament prostheses. Several years ago, we began functionalizing PET fabrics using anionic polymers to enhance their biocompatibility, cell adhesion, proliferation and functional performance as PET ligament prostheses. Polymer functionalization followed a grafting-from process from virgin PET surfaces subject to spin-finish oil additive removal under Soxhlet extraction to remove residual fiber manufacturing oil. Nevertheless, with increasing time from manufacture, PET fabrics stored without a spin finish removal step exhibited degradation of spin finish oil, leading to (1) incomplete surface cleaning, and (2) PET surface degradation. Moreover, oxidizing agents present in the residual degraded oil prevented reliable functionalization of the prosthesis fibers in these PET fabrics. This study compares effects of PET fabric/spin finish oil storage on PET fabric anionic polymer functionalization across two PET fabric ligament storage groups: (1) 2- and 10- year old ligaments, and (2) 26-year old ligaments. Strong interactions between degraded spin finish oil and PET fiber surfaces after long storage times were demonstrated via extraction yield; oil chemistry changed assessed by spectral analysis. Polymer grafting/functionalization efficiency on stored PET fabrics was correlated using atomic force microscopy, including fiber surface roughness and relationships between grafting degree and surface Young’s modulus. New PET fabric Young’s modulus significantly decreased by anionic polymer functionalization (to 96%, grafting degree 1.6 µmol/g) and to reduced modulus and efficiency (29%) for 10 years storage fabric (grafting degree ~ 1 µmol/g). As fiber spin finish is mandatory in biomedically applicable fiber fabrication, assessing effects of spin finish oil on commercial polymer fabrics after longer storage under various conditions (UV light, temperature) is necessary to understand possible impacts on fiber degradation and surface functionalization.

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Dynamic Single-Fiber Pull-Out of Polypropylene Fibers Produced with Different Mechanical and Surface Properties for Concrete Reinforcement

Materials ◽

10.3390/ma14040722 ◽

2021 ◽

Vol 14 (4) ◽

pp. 722

Author(s):

Enrico Wölfel ◽

Harald Brünig ◽

Iurie Curosu ◽

Viktor Mechtcherine ◽

Christina Scheffler

Keyword(s):

Tensile Strength ◽

Dynamic Loading ◽

Melt Spinning ◽

Structural Changes ◽

High Surface ◽

Single Fiber ◽

Scanning Calorimetry ◽

Matrix Interaction ◽

Pull Out ◽

Fiber Matrix

In strain-hardening cement-based composites (SHCC), polypropylene (PP) fibers are often used to provide ductility through micro crack-bridging, in particular when subjected to high loading rates. For the purposeful material design of SHCC, fundamental research is required to understand the failure mechanisms depending on the mechanical properties of the fibers and the fiber–matrix interaction. Hence, PP fibers with diameters between 10 and 30 µm, differing tensile strength levels and Young’s moduli, but also circular and trilobal cross-sections were produced using melt-spinning equipment. The structural changes induced by the drawing parameters during the spinning process and surface modification by sizing were assessed in single-fiber tensile experiments and differential scanning calorimetry (DSC) of the fiber material. Scanning electron microscopy (SEM), atomic force microscopy (AFM) and contact angle measurements were applied to determine the topographical and wetting properties of the fiber surface. The fiber–matrix interaction under quasi-static and dynamic loading was studied in single-fiber pull-out experiments (SFPO). The main findings of microscale characterization showed that increased fiber tensile strength in combination with enhanced mechanical interlocking caused by high surface roughness led to improved energy absorption under dynamic loading. Further enhancement could be observed in the change from a circular to a trilobal fiber cross-section.

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Investigation of Damage Evolution in Heterogeneous Rock Based on the Grain-Based Finite-Discrete Element Model

Materials ◽

10.3390/ma14143969 ◽

2021 ◽

Vol 14 (14) ◽

pp. 3969

Author(s):

Shirui Zhang ◽

Shili Qiu ◽

Pengfei Kou ◽

Shaojun Li ◽

Ping Li ◽

...

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Tensile Strength ◽

Grain Orientation ◽

Damage Evolution ◽

Discrete Element ◽

Uniaxial Tensile ◽

Tensile Cracks ◽

Rock Heterogeneity ◽

Heterogeneous Rock

Granite exhibits obvious meso-geometric heterogeneity. To study the influence of grain size and preferred grain orientation on the damage evolution and mechanical properties of granite, as well as to reveal the inner link between grain size‚ preferred orientation, uniaxial tensile strength (UTS) and damage evolution, a series of Brazilian splitting tests were carried out based on the combined finite-discrete element method (FDEM), grain-based model (GBM) and inverse Monte Carlo (IMC) algorithm. The main conclusions are as follows: (1) Mineral grain significantly influences the crack propagation paths, and the GBM can capture the location of fracture section more accurately than the conventional model. (2) Shear cracks occur near the loading area, while tensile and tensile-shear mixed cracks occur far from the loading area. The applied stress must overcome the tensile strength of the grain interface contacts. (3) The UTS and the ratio of the number of intergrain tensile cracks to the number of intragrain tensile cracks are negatively related to the grain size. (4) With the increase of the preferred grain orientation, the UTS presents a “V-shaped” characteristic distribution. (5) During the whole process of splitting simulation, shear microcracks play the dominant role in energy release; particularly, they occur in later stage. This novel framework, which can reveal the control mechanism of brittle rock heterogeneity on continuous-discontinuous trans-scale fracture process and microscopic rock behaviour, provides an effective technology and numerical analysis method for characterizing rock meso-structure. Accordingly, the research results can provide a useful reference for the prediction of heterogeneous rock mechanical properties and the stability control of engineering rock masses.

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Flammability, morphological and mechanical properties of sugar palm fiber/polyester yarn-reinforced epoxy hybrid biocomposites with magnesium hydroxide flame retardant filler

Textile Research Journal ◽

10.1177/00405175211008615 ◽

2021 ◽

pp. 004051752110086

Author(s):

MJ Suriani ◽

SM Sapuan ◽

CM Ruzaidi ◽

DS Nair ◽

RA Ilyas

Keyword(s):

Tensile Strength ◽

Surface Morphology ◽

Flame Retardant ◽

Tensile Properties ◽

Magnesium Hydroxide ◽

Building Materials ◽

Epoxy Composite ◽

Sem Analysis ◽

Palm Fiber ◽

Sugar Palm Fiber

This paper aims to study the surface morphology, flammability and tensile properties of sugar palm fiber (SPF) hybrid with polyester (PET) yarn-reinforced epoxy composite with the addition of magnesium hydroxide (Mg(OH)2) as a flame retardant. The composites were prepared by hybridized epoxy and Mg(OH)2/PET with different amounts of SPF contents (0%, 20%, 35% and 50%) using the cold press method. Then these composites were tested by horizontal burning analysis, tensile strength testing and scanning electron microscopy (SEM) analysis. The specimen with 35% SPF (Epoxy/PET/SPF-35) with the incorporation of Mg(OH)2 as a flame retardant showed the lowest burning rate of 13.25 mm/min. The flame took a longer time to propagate along with the Epoxy/PET/SPF-35 specimen and at the same time producing char. Epoxy/PET/SPF-35 also had the highest tensile strength of 9.69 MPa. Tensile properties of the SPF hybrid with PET yarn (SPF/PET)-reinforced epoxy composite was decreased at 50% SPF content due to the lack of interfacial bonding between the fibers and matrix. Surface morphology analysis through SEM showed uniform distribution of the SPF and matrix with less adhesion, which increased the flammability and reduced the tensile properties of the hybrid polymeric composites. These composites have potential to be utilized in various applications, such as automotive components, building materials and in the aerospace industry.

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BRAZILIAN TENSILE STRENGTH AND ITS RELATIONSHIP WITH UNIAXIAL TENSILE STRENGTH

Фундаментальные и прикладные вопросы горных наук ◽

10.15372/fpvgn2021080109 ◽

2021 ◽

Vol 8 (1) ◽

pp. 66-72

Author(s):

V. P. Efimov

Keyword(s):

Tensile Strength ◽

Uniaxial Tensile ◽

Brazilian Tensile Strength ◽

Uniaxial Tensile Strength

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Effects of Gd, Y Content on the Microstructure and Mechanical Properties of Mg-Gd-Y-Nd-Zr Alloy

Metals ◽

10.3390/met8100790 ◽

2018 ◽

Vol 8 (10) ◽

pp. 790 ◽

Cited By ~ 4

Author(s):

Changping Tang ◽

Kai Wu ◽

Wenhui Liu ◽

Di Feng ◽

Xuezhao Wang ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Ultimate Tensile Strength ◽

Solution Treatment ◽

Age Hardening ◽

Uniaxial Tensile ◽

Microstructure And Mechanical Properties ◽

Shaped Particle ◽

Zr Alloy ◽

Non Equilibrium

The effects of Gd, Y content on the microstructure and mechanical properties of Mg-Gd-Y-Nd-Zr alloy were investigated using hardness measurements, X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), and uniaxial tensile testing. The results indicate that the alloys in as-cast condition mainly consist of α-Mg matrix and non-equilibrium eutectic Mg5.05RE (RE = Gd, Y, Nd). After solution treatment, the non-equilibrium eutectics dissolved into the matrix but some block shaped RE-rich particles were left at the grain boundaries and within grains. These particles are especially Y-rich and deteriorate the mechanical properties of the alloys. Both the compositions of the eutectic and the block shaped particle were independent of the total Gd, Y content of the alloys, but the number of the particles increases as the total Gd, Y content increases. The ultimate tensile strength increases as the total Gd, Y content decreases. A Mg-5.56Gd-3.38Y-1.11Nd-0.48Zr alloy with the highest ultimate tensile strength of 280 MPa and an elongation of 1.3% was fabricated. The high strength is attributed to the age hardening behavior and the decrease in block shaped particles.

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Relationship between physical and mechanical properties of accelerated weathering and outdoor weathering of PVC-coated membrane material under tensile stress

Journal of Industrial Textiles ◽

10.1177/1528083716639062 ◽

2016 ◽

Vol 47 (2) ◽

pp. 197-210 ◽

Cited By ~ 4

Author(s):

Xudong Yang ◽

Xiuting Jiang ◽

Jiyong Hu ◽

Fangjuan Wang ◽

Chun Hu

Keyword(s):

Tensile Strength ◽

Physical And Mechanical Properties ◽

Accelerated Weathering ◽

Membrane Material ◽

Whiteness Index ◽

Carbonyl Index ◽

Tensile Stresses ◽

The Relationship ◽

Coated Membrane ◽

Outdoor Weathering

To estimate the photo-oxidation aging performance of PVC-coated membrane material in atmospheric conditions under tensile stresses, the relationship between physical and mechanical properties under accelerated weathering test and outdoor weathering test is studied with the same cumulative UV radiation energy. And then, both tensile strength and whiteness index were measured and compared to characterize the property change of membrane material after aging under four different tensile stresses (0%, 5%, 10% and 20% of the breaking strength), respectively. In addition, FTIR spectrometry was applied to characterize the chemical components of the samples under different weathering conditions, and the carbonyl index was extracted. The results show that there were significant differences of tensile strength and carbonyl index between two kinds of aging conditions, whereas with the increasing tensile stresses, the whiteness index represented a consistent increasing deviation of accelerated weathering from the outdoor weathering. However, the relationship have been built between both whiteness index and tensile strength retention of accelerated weathering and those of outdoor weathering conditions after a Schwarzschild’s modification. Therefore, the service lifespan of PVC-coated membrane materials can be evaluated by accelerated weathering tests under tensile stresses.

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