PREPARATION OF BLENDING COMPOSITIONS BASED ON SECONDARY POLYPROPYLENE WITH CONTROLLED PHYSICO-MECHANICAL PROPERTIES

It was investigated the effect of the method of obtaining polymer composites based on the blend of polymers over a wide range of their ratios on the rheological and physical-mechanical properties. The composites were prepared (using pressing or pressure die casting) on the basis of secondary polypropylene (PP) and the following polymers: 1) ultra high molecular polyethylene (UHMPE); 2) ethylene propylene diene monomer (EPDM); 3) secondary low pressure polyethylene (LPPE). Pressing was carried out on an automatic hydraulic press "AutoMH-NE" (Carver, the USA) at 210°C and endurance under pressure of 7000 kgfs within 3 min. Injection molding was performed using a Babyplast automatic molding machine of the horizontal type with an injection volume of up to 15 cm3. In both cases, the compositions also went through a stage of the preliminary mixture at the laboratory station (plastograf) of "PlastographEC" (Brabender, Germany) within 15 min at a load of 200 N. Estimation of rheological properties of the polymer composition melts was performed using a Haake Mars III rheometer. The deformation-strength properties were studied according to the State Standard GOST 11262-80 with a tensile testing machine "Shimadzu AGS-X". Using the data of relative rheometry, it is determined for all the systems studied (blends PP with UHMPE, EPDM, and LPPE) that variation of the maximum torque with composite composition is non-additive. This seems to be due to the occurring phase reversal. The present fact finds its support when performing rheological investigations using absolute rheometry. It is shown that variations in the phase structure of composites occurring in the phase reversal area lead to the corresponding changes in the deformation-strength properties of composites.

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

Metals ◽

10.3390/met11040548 ◽

2021 ◽

Vol 11 (4) ◽

pp. 548 ◽

Cited By ~ 1

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.

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Studies on Nanostructured Polyurethane/Clay Interpenetrating Polymer Networks

Materials Science Forum ◽

10.4028/www.scientific.net/msf.475-479.1001 ◽

2005 ◽

Vol 475-479 ◽

pp. 1001-1004

Author(s):

Ninglin Zhou ◽

Xiao Xian Xia ◽

Li Li ◽

Shao Hua Wei ◽

Jian Shen

Keyword(s):

Mechanical Properties ◽

Polymer Networks ◽

Testing Machine ◽

Physical And Mechanical Properties ◽

Interpenetrating Polymer Networks ◽

Absorption Properties ◽

Tensile Testing Machine ◽

Swelling Agent ◽

Silicate Layers ◽

Polyurethane Matrix

A novel exfoliated polyurethane (PU)/clay Interpenetrating Polymer Networks (IPNs) nanocomposite has been synthesized with polyurethane and organoclay. MTPAC is used as swelling agent to treat Na-montmorillonite for forming organoclay. The results indicate that there is very good compatibility between organoclay and PU. Nanoscale silicate dispersion was analyzed by XRD. The mechanical properties of the nanocomposites have been measured by tensile testing machine. The nanocomposites show obviously improved physical and mechanical properties when compared with the pure polymer. Additionally, PU /MTPAC- clay shows lower water absorption properties than pure PU do. In addition, the reinforcing and intercalating mechanism of silicate layers in polyurethane matrix are discussed.

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The Development and the Study of the Properties of Hydrosorption Material Based on a Blended Thermoplastic Vulcanisate

International Polymer Science and Technology ◽

10.1177/0307174x1704400802 ◽

2017 ◽

Vol 44 (8) ◽

pp. 9-14

Author(s):

M.F. Galikhanov ◽

D.M. Akhmedzyanova ◽

N.R. Nikitin

Keyword(s):

Diffusion Processes ◽

Testing Machine ◽

Strength Properties ◽

Water Soluble ◽

Butadiene Rubber ◽

Tensile Testing Machine ◽

Water Soluble Polymer ◽

Electret State ◽

Swelling Rate ◽

Negative Effect

Hydrosorption thermoplastic vulcanisates (TPVs) with a controllable swelling rate have been developed. They contain low-density polyethylene (LDPE), nitrile butadiene rubber (NBR), and sodium carboxymethyl cellulose (Na-CMC) – a water-soluble polymer (WSP). They were mixed on a laboratory mill in two stages and vulcanised at a temperature of 170°C. At the first stage, the NBR with a vulcanising system and carbon black were mixed with the WSP at 50°C, and at the second stage this composite was mixed with the polyethylene (PE) at 140°C. The hydrosorption, deformation and strength, and electret properties of the obtained TPVs were studied. The study of the sorption properties under conditions of limited and unlimited access of water showed that composites consisting of 25% polyethylene and 75% WSP swell in water by ∼28%, and here processes of migration of the WSP out of the composites are absent. The deformation and strength properties were determined on an Inspekt Mini TR-3 kN tensile testing machine. The level of deformation and strength characteristics of the obtained TPVs is not high, which is due to the low adhesion between the PE and the polar NBR, and also between the NBR and the WSP. However, for seals and gaskets, the achievable level of strength properties is quite adequate. An electret state of the TPVs was obtained in a negative corona discharge as they cooled down after heating to 90°C. Washers were manufactured from the developed TPVs, and they were tested for their sealing capacity. It was shown that the electret state inhibits the process of swelling of the TPVs in water, which is due to the negative effect of the electric field on the rate at which wetting, dissolution, and diffusion processes take place. However, during service, the electret state of articles manufactured from the developed TPVs rapidly relaxes, after which the swelling process occurs at a steady rate. This makes it possible to carry out assembly work involving the fitting or replacement of seals made of the hydrosorption TPVs.

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Influence Study of Plasticizer Compatibility on Strength Properties of Ethylene-Vinyl Acetate

Materials Science Forum ◽

10.4028/www.scientific.net/msf.935.79 ◽

2018 ◽

Vol 935 ◽

pp. 79-83

Author(s):

A.N. Volotskoy ◽

Yuriy V. Yurkin ◽

V.V. Avdonin

Keyword(s):

Mechanical Properties ◽

Vinyl Acetate ◽

Ethylene Vinyl Acetate ◽

Dynamic Mechanical Properties ◽

Strength Properties ◽

Polymer Materials ◽

Strength Characteristics ◽

Actual Problem ◽

Urgent Task ◽

Wide Range

This research is devoted to the actual problem of the development of damping polymer materials which are effective in a wide range of temperatures and having satisfactory strength characteristics. There are many works devoted to the study of dynamic mechanical properties of filled composites, but most do not take into account the influence of plasticizer on the strength properties of the polymer, as they change its characteristics for the worse. In this respect, the study and comparison of the mechanical properties of the polymer base with the introduction of different types and concentrations of plasticizers is an urgent task. According to the received regularities it was possible to define the type, concentration and boundaries of the polarity of the plasticizer, which reduces the strength characteristics of ethylene-vinyl acetate to a lesser degree.

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Fatigue and tensile behaviors of fiber-reinforced thermosetting composites embedded with nanoparticles

Journal of Composite Materials ◽

10.1177/0021998318790093 ◽

2018 ◽

Vol 53 (6) ◽

pp. 709-718 ◽

Cited By ~ 2

Author(s):

Moustafa Mahmoud Yousry Zaghloul ◽

Yasser S Mohamed ◽

Hassan El-Gamal

Keyword(s):

Mechanical Properties ◽

Glass Fiber ◽

Cellulose Nanocrystals ◽

Testing Machine ◽

Material Design ◽

Fatigue Properties ◽

Fiber Reinforced ◽

Molding Process ◽

Glass Fiber Reinforced ◽

Wide Range

The development of studying nanocomposites has grown up rapidly in the last decade. The objective of the current research is to study the influence of incorporating cellulose nanocrystals on the mechanical properties of polyester resins, as well as to develop continuous filament e-glass fiber-reinforced polyester nanocomposites, which combine traditional composites with the added advantages of nanocomposites. Cellulose nanocrystals were uniformly dispersed into the polyester resin by an ultrasonic processor. The incorporation and dispersion of cellulose nanocrystals were a state-of-the-art method aimed at overcoming poor dispersion problems at low weight fractions of nanoparticles. Three weight percentages of cellulose nanocrystals were prepared, which were 2%, 4% and 6%. Fatigue and tensile specimens were manufactured by resin transfer molding process. Cellulose nanocrystals were fully characterized by using X-ray diffraction, transmission electron microscopy, Fourier-transform infrared spectroscopy and zeta-sizer analysis. The optimum incorporation percentage of cellulose nanocrystals was used to prepare glass fiber-reinforced polyester specimens containing cellulose nanocrystals. Tensile and fatigue behaviors of glass fiber-reinforced polyester composites were evaluated by means of universal testing machine and rotating bending fatigue machine. A series of testing specimens for each property was examined in accordance with the corresponding ASTM and JIS standards. The experimental results showed that the addition of 4% cellulose nanocrystals to polyester matrix lead to the optimum tensile and fatigue properties. Mechanical properties were improved through the enhanced material design and proper selection of compatible nanoparticles, and adding cellulose nanocrystals in a weight fraction that does not affect the mechanical properties of glass fiber-reinforced polyester nanocomposites negatively. The presented design of material and geometry have shown promising results for wide range of applications, particularly in biomedical industry, energy and electronics.

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Effect of Er on Microstructure and Mechanical Properties of 5052 Aluminum Alloy with Big Width-To-Thickness Ratio

Materials ◽

10.3390/ma13030568 ◽

2020 ◽

Vol 13 (3) ◽

pp. 568

Author(s):

Xinwei She ◽

Xianquan Jiang ◽

Bao Qi ◽

Kang Chen

Keyword(s):

Mechanical Properties ◽

Aluminum Alloy ◽

Tensile Testing ◽

Testing Machine ◽

Thickness Ratio ◽

Tensile Testing Machine ◽

Microstructure And Mechanical Properties ◽

Long Time ◽

Scanning Electron ◽

Al Matrix

The effect of Er on microstructure and mechanical properties of the 5052 aluminum alloy with a big width-to-thickness ratio was investigated by a metallurgical microscope, scanning electron microscope and tensile testing machine. The results showed that the precipitates were slightly refined after Er addition and Al3Fe was transformed into Al6Fe and AlEr with/without a small amount of Fe or Si. The effect of Er on grain refinement was related to its content. When Er content was lower or higher than 0.4%, the grain would coarsen. Homogenization could refine the grain by controlling Er content and distribution in the Al matrix. Long time homogenization at high temperature would significantly reduce the strength of the 5052 aluminum alloy and 5052 aluminum alloys with low Er content, but help to improve the plasticity of those with high Er content. The ultimate tensile strength, yield strength and elongation of the as-cast 5052 aluminum alloy were 197 MPa, 117 MPa and 22.5% respectively. The strength was the highest, when Er content was 0.4 wt. % and the elongation was the best at 0.1 wt. % Er content.

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Progress in the Development of a Mechanical Properties Microprobe

MRS Bulletin ◽

10.1557/s0883769400054440 ◽

1986 ◽

Vol 11 (5) ◽

pp. 15-21 ◽

Cited By ~ 57

Author(s):

W. C. Oliver

Keyword(s):

Mechanical Properties ◽

Mechanical Response ◽

Quantitative Information ◽

General Term ◽

Strength Properties ◽

Physical Measurements ◽

Wide Range ◽

The Matrix ◽

Recent Developments ◽

Skilled Practitioner

A mechanical properties microprobe is an exciting concept. A system with the ability to evaluate the mechanical response of a sample with submicron spacial resolution would have an extremely wide range of applications. Recent developments in hardware and understanding have placed this goal within our grasp.In 1971, J.J.Gilman wrote the following in his article, “Hardness—A Strength Microprobe”:“Hardness measurements are at once among the most maligned and the most magnificent of physical measurements. Maligned because they are often misinterpreted by the uninitiated, and magnificent because they are so efficient in generating information for the skilled practitioner. They can quickly yield quantitative information about the elastic, anelastic, plastic, viscous, and fracture properties of a great variety of both isotropic and anisotropic solids. The tools that are used are simple and the sample sizes that are needed are typically small, sometimes submicroscopic. This makes it unnecessary to have large specimens in order to measure strength properties and makes it possible to measure the properties of various microscopic particles within the matrix phase of a polyphase metal, mineral, or ceramic material. This is why hardness may be considered to be a strength microprobe.”These statements are worth repeating for two reasons. First, they point out the largely untapped potential for microin-dentation tests to improve our understanding of the mechanical properties of materials. Second, it is the first mention of hardness tests in the context of a strength microprobe. In this article the more general term of microindentation tests will be used, since hardness is only one of many properties that can be measured with such tests. In addition, the term mechanical properties microprobe (MPM) will be used rather than strength microprobe-again, to note the wide variety of properties that can be measured.

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Microstructure and Mechanical Properties of Vacuum Sintered Austenitic Stainless Steel Parts

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.160-162.915 ◽

2010 ◽

Vol 160-162 ◽

pp. 915-920

Author(s):

Shao Jiang Lin ◽

Da Peng Feng ◽

Qi Nian Shi

Keyword(s):

Mechanical Properties ◽

Stainless Steel ◽

Austenitic Stainless Steel ◽

Vickers Hardness ◽

Room Temperature ◽

Sintering Temperature ◽

Testing Machine ◽

Microstructural Characterization ◽

Tensile Testing Machine ◽

Hardness Tester

This work presents the possibility of obtaining high density austenitic stainless steel parts by powder metallurgy (PM) and sintered in vacuum. Mechanical properties such as tensile strength, yield stress, elongation rate and Vickers hardness were measured by using a tensile testing machine and a Vickers hardness tester at room temperature. Microstructural characterization was performed by means of optical microscopy and scanning electron microscopy (SEM). The effect of sintering temperature on densification and mechanical properties of PM austenitic stainless steel has been investigated. The results show that density and mechanical properties were increased with the increase of sintering temperature, but when the sintering temperature is above 1340 °C, they increased slowly. The highest mechanical properties were obtained when sintering temperature was 1340 °C.

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Microstructure and Mechanical Properties of Mg-9Gd-4Y-0.5Zr Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.904.15 ◽

2017 ◽

Vol 904 ◽

pp. 15-18

Author(s):

Bo Bo Meng ◽

Quan An Li ◽

Xiao Ya Chen

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Solid Solution ◽

Tensile Testing ◽

Treatment Process ◽

Testing Machine ◽

Elongation Rate ◽

Heat Treatment Process ◽

Tensile Testing Machine ◽

Microstructure And Mechanical Properties

The effects of heat treatment on microstructure and mechanical properties of Mg-9Gd-4Y-0.5Zr alloy were studied by XRD, OM, SEM and tensile testing machine. The results show that the alloy mainly consists of α-Mg matrix, Mg5Gd and Mg24Y5. Through solid solution and aging heat treatment process, the tensile strength, yield strength and elongation rate respectively achieves 263.1MPa, 235.2MPa and 3.11%.

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Improving the shape stability and enhancing the properties of layer dependent material extruded biodegradable polylactic acid for thin implants

Rapid Prototyping Journal ◽

10.1108/rpj-05-2020-0108 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Alper Ekinci ◽

Xiaoxiao Han ◽

Andrew Gleadall ◽

Andrew Allan Johnson

Keyword(s):

Mechanical Properties ◽

Molecular Weight ◽

Polylactic Acid ◽

Testing Machine ◽

Degree Of Crystallinity ◽

Annealed Specimen ◽

Future Research ◽

Shape Stability ◽

Tensile Testing Machine ◽

Content Type

Purpose This paper aims to establish an appropriate annealing method, which is necessary for shape stability and to evaluate their potential degradation performance of 1-, 3- and 5-layer material extruded polylactic-acid specimens by enhancing their thermal and mechanical properties. Design/methodology/approach The distortion of each layered printed specimen subjected to degradation was calculated in x- and y-direction. Each layered specimen was subjected to annealing at 70°C, 80°C and 90°C for 2 h and at 80°C for 1, 4, 8 and 16 h. Thermal, molecular weight and mechanical properties were calculated using, differential scanning calorimetry, gel permeation chromatography and tensile testing machine, respectively. Findings In the x-direction, distortion was 16.08 mm for one-layer non-annealed printed specimens and decreased by 73% and 83% for 3- and 5-layer, respectively, while each layered non-annealed specimen subjected to degradation at 37°C for one month. Within the outlined study, annealing treatment enhances properties such as the degree of crystallinity (%χ) up to 34%, Young’s modulus (E) by 30% and ultimate tensile strength by 20% compared to the non-annealed specimens. Practical implications The future research accomplishments will be concentrated on the design, development and optimisation of degraded biomedical implants using material extrusion thin films including drug delivery system and fixation plates. Originality/value The printed thin specimens subjected to degradation were investigated. This research developed a new understanding of the effect of the annealing temperature and time on the mechanical, thermal and molecular weight properties for each layered specimen.

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