Dynamic Mechanical Analysis and Three-Body Abrasive Wear Behaviour of Thermoplastic Copolyester Elastomer Composites

Various amounts of short fibers (glass and carbon) and particulate fillers like polytetrafluoroethylene (PTFE), silicon carbide (SiC), and alumina (Al2O3) were systematically introduced into the thermoplastic copolyester elastomer (TCE) matrix for reinforcement purpose. The mechanical properties such as storage modulus, loss modulus, and Tanδby dynamic mechanical analysis (DMA) and three-body abrasive wear performance on a dry sand rubber wheel abrasion tester have been investigated. For abrasive wear study, the experiments were planned according toL27orthogonal array by considering three factors and three levels. The complex moduli for TCE hybrid composites were pushed to a higher level relative to the TCE filled PTFE composite. At lower temperatures (in the glassy region), the storage modulus increases with increase in wt.% of reinforcement (fiber + fillers) and the value is maximum for the composite with 40 wt.% reinforcement. The loss modulus and damping peaks were also found to be higher by the incorporation of SiC and Al2O3microfillers. The routine abrasive wear test results indicated that TCE filled PTFE composite exhibited better abrasion resistance. Improvements in the abrasion resistance, however, have not been achieved by short-fiber and particlaute filler reinforcements. From the Taguchi’s experimental findings, optimal combination of control factors were obtained for minimum wear volume and also predictive correlations were proposed. Further, the worn surface morphology of the samples was discussed.

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Viscoelastic Properties of Contemporary Bulk-fill Restoratives: A Dynamic-mechanical Analysis

Operative Dentistry ◽

10.2341/16-365-l ◽

2018 ◽

Vol 43 (3) ◽

pp. 307-314 ◽

Cited By ~ 5

Author(s):

JEX Ong ◽

AU Yap ◽

JY Hong ◽

AH Eweis ◽

NA Yahya

Keyword(s):

Dynamic Mechanical Analysis ◽

Storage Modulus ◽

Loss Tangent ◽

Viscoelastic Properties ◽

Loss Modulus ◽

Artificial Saliva ◽

Mechanical Analysis ◽

Distilled Water ◽

Glass Ionomer ◽

Dynamic Mechanical

SUMMARY This study investigated the viscoelastic properties of contemporary bulk-fill restoratives in distilled water and artificial saliva using dynamic mechanical analysis. The materials evaluated included a conventional composite (Filtek Z350), two bulk-fill composites (Filtek Bulk-fill and Tetric N Ceram), a bulk-fill giomer (Beautifil-Bulk Restorative), and two novel reinforced glass ionomer cements (Zirconomer [ZR] and Equia Forte [EQ]). The glass ionomer materials were also assessed with and without resin coating (Equia Forte Coat). Test specimens 12 × 2 × 2 mm of the various materials were fabricated using customized stainless-steel molds. After light polymerization/initial set, the specimens were removed from the molds, finished, measured, and conditioned in distilled water or artificial saliva at 37°C for seven days. The materials (n=10) were then subjected to dynamic mechanical testing in flexure mode at 37°C and a frequency of 0.1 to 10 Hz. Storage modulus, loss modulus, and loss tangent data were subjected to normality testing and statistical analysis using one-way analysis of variance/Dunnett's test and t-test at a significance level of p < 0.05. Mean storage modulus ranged from 3.16 ± 0.25 to 8.98 ± 0.44 GPa, while mean loss modulus ranged from 0.24 ± 0.03 to 0.65 ± 0.12 GPa for distilled water and artificial saliva. Values for loss tangent ranged from 45.7 ± 7.33 to 134.2 ± 12.36 (10−3). Significant differences in storage/loss modulus and loss tangent were observed between the various bulk-fill restoratives and two conditioning mediums. Storage modulus was significantly improved when EQ and ZR was not coated with resin.

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Damping Factor and Dynamic Mechanical Analysis of Glass Fibre Reinforced Polyester Composite

International Journal of Vehicle Structures and Systems ◽

10.4273/ijvss.11.3.13 ◽

2019 ◽

Vol 11 (3) ◽

Author(s):

G. Sathishkumar ◽

R. Sridhar ◽

S. Sivabalan ◽

S. Joseph Irudaya Raja

Keyword(s):

Dynamic Mechanical Analysis ◽

Storage Modulus ◽

Glass Fibre ◽

Loss Modulus ◽

Fibre Length ◽

Mechanical Analysis ◽

Fibre Content ◽

Damping Factor ◽

Dynamic Mechanical ◽

Polyester Composite

This study aims to evaluate the result of experimental examination conducted on free vibration characteristics and dynamic mechanical analysis over a range of temperature and five different frequencies of short glass fibre polyester composite. The effect of temperature on the storage modulus, loss modulus, and damping efficiency (tan δ) is determined. Synthetic reinforced material is created in random fibre orientation using hand lay-up method by domination of fibre length (10mm) and weight percent (5, 10, 15, 20%). Improvement in the fibre content will make a rise in the natural frequency and the storage modulus is maximum when fibre content of 20wt. % is introduced to the composite materials in the temperature ranges of 300-800°C. The peak of loss modulus and damping curves were lowered with respect to the fibre content. The properties were compared with neat polyester.

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Dynamic mechanical analysis and three-body abrasive wear behavior of epoxy nanocomposites

Journal of Reinforced Plastics and Composites ◽

10.1177/0731684412464914 ◽

2012 ◽

Vol 32 (1) ◽

pp. 61-71 ◽

Cited By ~ 5

Author(s):

B Suresha ◽

BL Ravishankar ◽

L Sukanya

Keyword(s):

Abrasive Wear ◽

Dynamic Mechanical Analysis ◽

Wear Behavior ◽

Mechanical Analysis ◽

Epoxy Nanocomposites ◽

Dynamic Mechanical ◽

Abrasive Wear Behavior ◽

Three Body

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Dynamic mechanical behaviour of kevlar and carbon-kevlar hybrid fibre reinforced polymer composites

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406220970600 ◽

2020 ◽

pp. 095440622097060

Author(s):

Pragati Priyanka ◽

Harlal Singh Mali ◽

Anurag Dixit

Keyword(s):

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Dynamic Mechanical Analysis ◽

Storage Modulus ◽

Composite Laminates ◽

Mechanical Analysis ◽

Textile Composites ◽

Elastic Behaviour ◽

Dynamic Mechanical

Comprehensive experimental results of dynamic mechanical analysis (DMA) of polymer reinforced textile composites are presented in the current investigation. Plain and 2x2 twill woven multilayer fabrics of monolithic kevlar and hybrid carbon-kevlar (C-K) are reinforced into the thermoset polymer matrix. Kevlar/epoxy and C-K/epoxy composite laminates are fabricated using an in-house facility of the vacuum-assisted resin infusion process. Variation of the visco-elastic behaviour (storage modulus, damping factor and glass transition temperature, Tg) along with time, temperature and frequency is studied for the composites. Dynamic mechanical analysis is performed under temperature sweep with frequency ranging from 1-50 Hz. Results depict the effect of inter yarn hybridisation of carbon with kevlar yarns on the storage modulus, damping performance, and creep behaviour of dry textile composites. Temperature swept dynamic characterisation is also performed to evaluate the degradation and damping performance of the composite laminates soaked in the deionised water at glass transition temperature Tg, ½ Tg, and ¾ Tg. The morphological study has been performed post the dynamic mechanical analysis using field emission scanning electron microscope.

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Dynamic Mechanical Analysis as a Complementary Technique for Stickiness Determination in Model Whey Protein Powders

Foods ◽

10.3390/foods9091295 ◽

2020 ◽

Vol 9 (9) ◽

pp. 1295

Author(s):

Laura O’Donoghue ◽

Md. Haque ◽

Sean Hogan ◽

Fathima Laffir ◽

James O’Mahony ◽

...

Keyword(s):

Glass Transition ◽

Dynamic Mechanical Analysis ◽

Whey Protein ◽

Loss Modulus ◽

Mechanical Analysis ◽

Whey Protein Concentrate ◽

Scanning Calorimetry ◽

Dynamic Mechanical ◽

Storage And Loss Moduli ◽

Lower Protein

The α-relaxation temperatures (Tα), derived from the storage and loss moduli using dynamic mechanical analysis (DMA), were compared to methods for stickiness and glass transition determination for a selection of model whey protein concentrate (WPC) powders with varying protein contents. Glass transition temperatures (Tg) were determined using differential scanning calorimetry (DSC), and stickiness behavior was characterized using a fluidization technique. For the lower protein powders (WPC 20 and 35), the mechanical Tα determined from the storage modulus of the DMA (Tα onset) were in good agreement with the fluidization results, whereas for higher protein powders (WPC 50 and 65), the fluidization results compared better to the loss modulus results of the DMA (Tα peak). This study demonstrates that DMA has the potential to be a useful technique to complement stickiness characterization of dairy powders by providing an increased understanding of the mechanisms of stickiness.

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Comparative investigation of physical, mechanical and thermomechanical characterization of dental composite filled with nanohydroxyapatite and mineral trioxide aggregate

e-Polymers ◽

10.1515/epoly-2016-0319 ◽

2017 ◽

Vol 17 (4) ◽

pp. 311-319 ◽

Cited By ~ 4

Author(s):

Anoj Meena ◽

Harlal Singh Mali ◽

Amar Patnaik ◽

Shiv Ranjan Kumar

Keyword(s):

Compressive Strength ◽

Dynamic Mechanical Analysis ◽

Storage Modulus ◽

Water Sorption ◽

Mineral Trioxide Aggregate ◽

Mechanical Analysis ◽

Comparative Investigation ◽

Dental Composite ◽

Dynamic Mechanical

AbstractThis study presents comparative investigation of adding nanohydroxyapatite (HA) (5–20 wt.%) and mineral trioxide aggregate (MTA) (5–20 wt.%) on the physical, mechanical and thermomechanical characterization of dental composite. The performances of both experimental composites were assessed through various physical, mechanical and thermomechanical tests such as void content test, microhardness test, compressive strength test, dynamic mechanical analysis and thermogravimetric analysis. The result of experiment indicated that the addition of 5 wt.% of HA increased the water sorption, hardness and compressive strength by 50.47%, 13.46% and 62.35%, respectively, whereas the addition of 5 wt.% of MTA increased the water sorption, hardness and compressive strength by 19.23%, 100% and 5.44%, respectively. Dynamic mechanical analysis results revealed that the addition of 5 wt.% HA increased the storage modulus by 10.21%, whereas the addition of 5 wt.% of MTA decreased the storage modulus by 11.79%. The filler HA proved to be better choice in term of thermal stability behavior as compare to MTA filler.

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Mechanical Properties of Coil Coating Evaluated with Dynamic Mechanical Analysis in Daul Cantilever

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.353-358.1729 ◽

2007 ◽

Vol 353-358 ◽

pp. 1729-1732 ◽

Cited By ~ 2

Author(s):

Lei Chen ◽

Hong Liang Pan

Keyword(s):

Mechanical Properties ◽

Dynamic Mechanical Analysis ◽

Loss Modulus ◽

Paint Layer ◽

Mechanical Analysis ◽

Curing Temperature ◽

Mode Analysis ◽

Dynamic Mechanical ◽

Preparation Conditions ◽

Coil Coating

The storage modulus, loss modulus, loss tangent (tanδ), stress and strain have been determined for painted steel specimens by dynamic mechanical analysis (DMA) operated in Dual Cantilever mode. Analysis of the composite system enabled the elastic modulus of the paint layer to be calculated and the result can be useful to analyze the mechanical properties of the coil coating. The calculation was found to be very sensitive to the geometry (especially thickness of the substrate and coating) and properties of the substrate and coating, leading to considerable variability in the calculated coating modulus. The DMA method was successful in detecting the glass transition temperature (Tg) as a peak in the tanδ curve. The value of Tg is sensitive to the preparation conditions (e.g. curing temperature) and composition of the paint. The results show that DMA in Dual Cantilever can be useful as a characterization tool for painted steel.

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Dynamic Mechanical Analysis of Fly Ash Filled Polyurea Elastomer

Journal of Engineering Materials and Technology ◽

10.1115/1.4002650 ◽

2010 ◽

Vol 133 (1) ◽

Cited By ~ 27

Author(s):

Jing Qiao ◽

Alireza V. Amirkhizi ◽

Kristin Schaaf ◽

Sia Nemat-Nasser

Keyword(s):

Glass Transition ◽

Fly Ash ◽

Dynamic Mechanical Analysis ◽

Volume Fraction ◽

Loss Modulus ◽

Mechanical Analysis ◽

Temperature Dependent ◽

Dynamic Mechanical ◽

Storage And Loss Moduli ◽

Temperature Superposition

In this work, the material properties of a series of fly ash/polyurea composites were studied. Dynamic mechanical analysis was conducted to study the effect of the fly ash volume fraction on the composite’s mechanical properties, i.e., on the material’s frequency- and temperature-dependent storage and loss moduli. It was found that the storage and loss moduli of the composite both increase as the fly ash volume fraction is increased. The storage and loss moduli of the composites relative to those of pure polyurea initially increase significantly with temperature and then slightly decrease or stay flat, attaining peak values around the glass transition region. The glass transition temperature (measured as the temperature at the maximum value of the loss modulus) shifted toward higher temperatures as the fly ash volume fraction increased. Additionally, we present the storage and loss moduli master curves for these materials obtained through application of the time-temperature superposition on measurements taken at a series of temperatures.

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