scholarly journals Effect of degree of substitution on the mechanical and thermomechanical properties of lauroyl cellulose ester films

e-Polymers ◽  
2006 ◽  
Vol 6 (1) ◽  
Author(s):  
Nicolas Joly ◽  
Patrick Martin ◽  
Luc Liénard ◽  
Delphine Rutot ◽  
Fabrice Stassin ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Elastic Modulus ◽  
Mechanical Analysis ◽  
Thermomechanical Properties ◽  
Degree Of Substitution ◽  
Cellulose Ester ◽  
Plastic Films ◽  
Ester Formation ◽  
Homogeneous Media

AbstractCellulose-based plastic films were prepared in homogeneous media with a range of lauroyl fatty acid attachments by ester formation, expressed as the degree of substitution (DS). The esters were cast to form films and their mechanical properties studied. This study showed a surprising relationship between DS and elastic modulus as well as DS and tensile strength, where a peak was observed at DS 2.4. The unexpected variation of static elastic modulus (E) was confirmed by dynamic mechanical analysis (DMA) and this trend was also observed for glass transition temperature (Tg). These results are discussed in relation to sample cohesion.

scholarly journals Influence of Alumina Nanofibers Sintered by the Spark Plasma Method on Nickel Mechanical Properties

Metals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 548 ◽  
Author(s):  
Leonid Agureev ◽  
Valeriy Kostikov ◽  
Zhanna Eremeeva ◽  
Svetlana Savushkina ◽  
Boris Ivanov ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Elastic Modulus ◽  
Strength Properties ◽  
Alumina Nanoparticles ◽  
Metal Powders ◽  
Wide Range ◽  
The Matrix ◽  
Spark Plasma ◽  
Average Size

The article presents the study of alumina nanoparticles’ (nanofibers) concentration effect on the strength properties of pure nickel. The samples were obtained by spark plasma sintering of previously mechanically activated metal powders. The dependence of the grain size and the relative density of compacts on the number of nanofibers was investigated. It was found that with an increase in the concentration of nanofibers, the average size of the matrix particles decreased. The effects of the nanoparticle concentration (0.01–0.1 wt.%) on the elastic modulus and tensile strength were determined for materials at 25 °C, 400 °C, and 750 °C. It was shown that with an increase in the concentration of nanofibers, a 10–40% increase in the elastic modulus and ultimate tensile strength occurred. A comparison of the mechanical properties of nickel in a wide range of temperatures, obtained in this work with materials made by various technologies, is carried out. A description of nanofibers’ mechanisms of influence on the structure and mechanical properties of nickel is given. The possible impact of impurity phases on the properties of nickel is estimated. The tendency of changes in the mechanical properties of nickel, depending on the concentration of nanofibers, is shown.

scholarly journals Numerical Studies of the Effects of Water Capsules on Self-Healing Efficiency and Mechanical Properties in Cementitious Materials

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Haoliang Huang ◽  
Guang Ye
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Elastic Modulus ◽  
Cementitious Materials ◽  
Self Healing ◽  
Negative Effects ◽  
Numerical Studies ◽  
Healing Efficiency ◽  
The Impact ◽  
Positive Effect

In this research, self-healing due to further hydration of unhydrated cement particles is taken as an example for investigating the effects of capsules on the self-healing efficiency and mechanical properties of cementitious materials. The efficiency of supply of water by using capsules as a function of capsule dosages and sizes was determined numerically. By knowing the amount of water supplied via capsules, the efficiency of self-healing due to further hydration of unhydrated cement was quantified. In addition, the impact of capsules on mechanical properties was investigated numerically. The amount of released water increases with the dosage of capsules at different slops as the size of capsules varies. Concerning the best efficiency of self-healing, the optimizing size of capsules is 6.5 mm for capsule dosages of 3%, 5%, and 7%, respectively. Both elastic modulus and tensile strength of cementitious materials decrease with the increase of capsule. The decreasing tendency of tensile strength is larger than that of elastic modulus. However, it was found that the increase of positive effect (the capacity of inducing self-healing) of capsules is larger than that of negative effects (decreasing mechanical properties) when the dosage of capsules increases.

Graphite/Bio-Based Epoxy Composites: The Mechanical Properties Interface

2015 ◽  
Vol 799-800 ◽  
pp. 115-119 ◽  
Author(s):  
Anika Zafiah M. Rus ◽  
Nur Munirah Abdullah ◽  
M.F.L. Abdullah ◽  
M. Izzul Faiz Idris
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Elastic Modulus ◽  
Filler Content ◽  
Weight Percent ◽  
Epoxy Composites ◽  
Elongation At Break ◽  
Graphite Content ◽  
Dispersion Condition ◽  
Strong Interfacial Bonding

Graphite reinforced bio-based epoxy composites with different particulate fractions of graphite were investigated for mechanical properties such as tensile strength, elastic modulus and elongation at break. The graphite content was varied from 5 wt.%, 10 wt.%, 15 wt.%, 20 wt.%, 25 wt.%, 30 wt.% by weight percent in the composites. The results showed that the mechanical properties of the composites mainly depend on dispersion condition of the treated graphite filler, aggregate structure and strong interfacial bonding between treated graphite in the bio-based epoxy matrix. The composites showed improved tensile strength and elastic modulus with increase treated graphite weight loading. This also revealed the composites with increasing filler content was decreasing the elongation at break.

Test Methods for Mechanical Properties of Structural Adhesives

2010 ◽  
Vol 97-101 ◽  
pp. 814-817 ◽  
Author(s):  
Jun Deng
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Shear Strength ◽  
Elastic Modulus ◽  
Butt Joint ◽  
Test Methods ◽  
Joint Specimen ◽  
Lap Shear ◽  
Better Than

One of the greatest drawbacks to predicting the behaviour of bonded joints has been the lack of reliable data on the mechanical properties of adhesives. In this study, methods for determining mechanical properties of structural adhesive were discussed. The Young’s modulus, Poisson’s ratio and tensile strength of the adhesive were tested by dogbone specimens (bulk form) and butt joint specimens (in situ form). The shear modulus and shear strength were test by V-notched specimens (bulk form) and thick adherend lap-shear (TALS) joint specimens (in situ form). The test results show that the elastic modulus provided by the manufacturer is too low, the dogbone specimen is better than the butt joint specimen to test the tensile strength and elastic modulus and the TALS joint specimen is better than the V-notched specimen to test the shear strength.

scholarly journals Styrene–Acrylic Emulsion with “Transition Layer” for Damping Coating: Synthesis and Characterization

Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1406
Author(s):  
Daoyuan Chen ◽  
Mingjin Ding ◽  
Zhixiong Huang ◽  
Yanbing Wang
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Transition Layer ◽  
Testing Machine ◽  
Dynamic Mechanical Properties ◽  
Mechanical Analysis ◽  
Latex Film ◽  
Seeded Emulsion Polymerization ◽  
Acrylic Emulsion ◽  
Dynamic Mechanical

In order to study the dynamic mechanical properties of styrene–acrylic latex with a core/shell structure, a variety of latexes were synthesized by semi-continuous seeded emulsion polymerization based on “particle design” with the same material. The latexes were characterized by rotary viscosimeter, dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), transmission electron microscope (TEM), dynamic mechanical analysis (DMA), and universal testing machine. The effects of difference at the glass transition temperature (Tg) of core and shell and the introduction of the “transition layer” on the damping and mechanical properties of latex film were studied. The results indicate that as the Tg of core and shell gets closer, the better the compatibility of core and shell, from phase separation to phase continuity. Furthermore, the introduction of the “transition layer” can effectively improve the tensile strength and tan δ (max) of the latex film. The tensile strength and maximum loss factor (f = 1 Hz) of latex with the “transition layer” increased by 36.73% and 29.11% respectively compared with the latex without the “transition layer”. This work provides a reference for the design of emulsion for damping coating.

Effect of Wood Filler Concentration on Physical and Mechanical Properties of PLA-Based Composites

2021 ◽  
Vol 887 ◽  
pp. 110-115
Author(s):  
G.A. Sabirova ◽  
R.R. Safin ◽  
N.R. Galyavetdinov
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Elastic Modulus ◽  
Composite Materials ◽  
Impact Strength ◽  
Wood Flour ◽  
Experimental Studies ◽  
Physical And Mechanical Properties ◽  
Filler Concentration ◽  
High Concentration

This paper presents the findings of experimental studies of the physical and mechanical properties of wood-filled composites based on polylactide (PLA) and vegetable filler in the form of wood flour (WF) thermally modified at 200-240 °C. It also reveals the dependence of the tensile strength, impact strength, bending elastic modulus, and density of composites on the amount of wood filler and the temperature of its thermal pre-modification. We established that an increase in the concentration of the introduced filler and the degree of its heat treatment results in a decrease of the tensile strength, impact strength and density of composite materials, while with a lower binder content, thermal modification at 200 °C has a positive effect on bending elastic modulus. We also found that 40 % content of a wood filler heated to 200 °C is sufficient to maintain relatively high physical and mechanical properties of composite materials. With a higher content of a wood filler, the cost can be reduced but the quality of products made of this material may significantly deteriorate. However, depending on the application and the life cycle of this product, it is possible to develop a formulation that includes a high concentration of filler.

scholarly journals Effect of Cold Drawing on Mechanical Properties of Biodegradable Fibers

2017 ◽  
Vol 15 (1) ◽  
pp. 70-76 ◽  
Author(s):  
Francesco Paolo La Mantia ◽  
Manuela Ceraulo ◽  
Maria Chiara Mistretta ◽  
Marco Morreale
Keyword(s):  
Mechanical Properties ◽  
Elastic Modulus ◽  
Biodegradable Polymers ◽  
Biodegradable Polymer ◽  
Cold Drawing ◽  
Thermal Characterization ◽  
Systematic Investigation ◽  
Thermomechanical Properties ◽  
Polymer Systems ◽  
The Impact

Purpose Biodegradable polymers are currently gaining importance in several fields, because they allow mitigation of the impact on the environment related to disposal of traditional, nonbiodegradable polymers, as well as reducing the utilization of oil-based sources (when they also come from renewable resources). Fibers made of biodegradable polymers are of particular interest, though, it is not easy to obtain polymer fibers with suitable mechanical properties and to tailor these to the specific application. The main ways to tailor the mechanical properties of a given biodegradable polymer fiber are based on crystallinity and orientation control. However, crystallinity can only marginally be modified during processing, while orientation can be controlled, either during hot drawing or cold stretching. In this paper, a systematic investigation of the influence of cold stretching on the mechanical and thermomechanical properties of fibers prepared from different biodegradable polymer systems was carried out. Methods Rheological and thermal characterization helped in interpreting the orientation mechanisms, also on the basis of the molecular structure of the polymer systems. Results and conclusions It was found that cold drawing strongly improved the elastic modulus, tensile strength and thermomechanical resistance of the fibers, in comparison with hot-spun fibers. The elastic modulus showed higher increment rates in the biodegradable systems upon increasing the draw ratio.

Renewable resources-based PTT [poly(trimethylene terephthalate)]/switchgrass fiber composites: The effect of compatibilization

2012 ◽  
Vol 85 (3) ◽  
pp. 521-532 ◽  
Author(s):  
Jeevan Prasad Reddy ◽  
Manjusri Misra ◽  
Amar Mohanty
Keyword(s):  
Mechanical Properties ◽  
Impact Strength ◽  
Renewable Resources ◽  
Melt Flow Index ◽  
Mechanical Analysis ◽  
Thermomechanical Properties ◽  
Flow Index ◽  
Methylene Diphenyl Diisocyanate ◽  
Trimethylene Terephthalate ◽  
The Impact

In this research, switchgrass (SG) fiber-reinforced poly(trimethylene terephthalate) (PTT) biocomposites were prepared by extrusion followed by injection molding machine. The methylene-diphenyl-diisocyanate-polybutadiene (MDIPB) prepolymer was used to enhance the impact strength of the biocomposites. In addition, the polymeric methylene-diphenyl-diisocyanate (PMDI) compatibilizer was used to enhance the mechanical properties of the composites. The effect of compatibilizer on mechanical, crystallization melting, thermomechanical, melt flow index (MFI), morphological, and thermal stability properties of the composites was studied. Thermomechanical properties of the biocomposites were studied by dynamic mechanical analysis (DMA). Scanning electron microscopy (SEM) was used to observe the interfacial adhesion between the fiber and matrix. The results showed that MDIPB and PMDI have a significant effect on the mechanical properties of the composites. The impact strength of MDIPB- and PMDI-compatibilized composites was increased by 87 % when compared to the uncompatibilized composite.

The influence of functionalization time of carbon nanotube on the mechanical properties of the epoxy composites

2017 ◽  
Vol 51 (12) ◽  
pp. 1693-1701 ◽  
Author(s):  
EA Zakharychev ◽  
EN Razov ◽  
Yu D Semchikov ◽  
NS Zakharycheva ◽  
MA Kabina
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Tensile Strength ◽  
Elastic Modulus ◽  
Carbon Nanotube ◽  
Composite Materials ◽  
Polymer Composites ◽  
Epoxy Composites ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

This paper investigates the structure, length, and percentage of functional groups of multi-walled carbon nanotubes (CNT) depending on the time taken for functionalization in HNO3 and H2SO4 mixture. The carbon nanotube content and influence of functionalization time on mechanical properties of polymer composite materials based on epoxy matrix are studied. The extreme dependencies of mechanical properties of carbon nanotube functionalization time of polymer composites were established. The rise in tensile strength of obtained composites reaches 102% and elastic modulus reaches 227% as compared to that of unfilled polymer. The composites exhibited best mechanical properties by including carbon nanotube with 0.5 h functionalization time.

Anisotropic Mechanical Properties of Rapid Prototyping Parts Fabricated by Stereolithography

2021 ◽  
Vol 13 (9) ◽  
pp. 1812-1819
Author(s):  
Na-Na Yang ◽  
Hao-Rui Liu ◽  
Ning Mi ◽  
Qi Zhou ◽  
Li-Qun He ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Elastic Modulus ◽  
Brittle Fracture ◽  
Fracture Surface ◽  
Elongation At Break ◽  
Build Orientation ◽  
Range Distribution ◽  
Anisotropic Mechanical Properties ◽  
Orientation Experiment

Stereolithography (SLA)-manufactured parts behave with anisotropic properties due to the varying interface orientations generated by the layer-based manufacturing process. Part build orientation is a very important factor of anisotropic mechanical properties. In this paper, the build orientation experiment was designed to study the anisotropic behaviour of the mechanical properties of the SLA parts based on the orientation relationship between the force and the layer. The results show that there are obvious brittle characteristics on the fracture surface of the specimens and microcracks perpendicular to the direction of the layer distributed on the side of the fracture. The mechanical properties under brittle fracture have different degrees of sensitivity to the build orientation. Among all the build orientations, whether a specimen is built flat or on an edge shows obvious difference in tensile strength, and the relative range distribution reaches 35%. The changes in elastic modulus and the elongation at break are the most obvious in different angles relative to the XY plane, and the relative range distribution reaches 62% and 56% respectively. In all the build orientations designed, the tensile strength is the largest when it is placed on the edge at 0° with Y-axis in the XY plane, the elastic modulus is the largest when it was placed vertically, and the elongation at break is the largest when it is placed flat at 45° with Y-axis in the XY plane.

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