scholarly journals The impact of non-vacuum electron beam treatment on the structure and properties of ultra-high molecular weight polyethylene

2020 ◽  
Vol 97 (1) ◽  
pp. 35-41
Author(s):  
Zh.B. Sagdoldina ◽  
◽  
B.K. Rakhadilov ◽  
К. Akatan ◽  
P. Kowalewski ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Electron Beam ◽  
Radiation Dose ◽  
Electron Beam Treatment ◽  
Scanning Calorimetry ◽  
Electron Beam Processing ◽  
Micro Level ◽  
The Impact ◽  
Ultra High Molecular Weight ◽  
Thermal Stability Of

The results of work on the impact of electron beam treatment on the structure, mechanical properties, microhardness, and thermal stability of ultra-high molecular polyethylene (PE-UHMW) are presented in this work. Electron beam processing was carried out on an industrial impulse accelerator ILU-10. The samples were irradiated with electrons with energies of 2.5 MeV, 3.5 MeV and 4.5 MeV, and the radiation dose varied from 2MGy to 9 MGy. It was determined by the method of differential scanning calorimetry that the melting temperature of the PE-UHMW polymer practically does not change for all samples, regardless of the radiation dose. After electron beam treatment, the morphology of the surfaces of the PE-UHMW polymer is significantly improved, spherulites are formed at the micro level, which indicate the displacement of polymer molecules under the influence of irradiation. It was revealed that during electron beam treatment oxidation occurs as a result of chemical reactions of the polyethylene chain with oxygen O2. Significant changes in the mechanical properties of the PE-UHMW polymer were not observed after electron beam treatment. However, a significant decrease in the elongation from 300 % to 10 % as a result of radiation aging was observed after electron beam treatment.The hardness of the PE-UHMW polymer varies slightly in the studied mode of electron beam processing.

scholarly journals Investigation of the Effects of Titanate as Coupling Agent and Some Inorganic Nanoparticles as Fillers on Mechanical Properties and Morphology of Soft PVC

2011 ◽  
Vol 2011 ◽  
pp. 1-9 ◽  
Author(s):  
Morteza Hajian ◽  
Gholam Ali Koohmareh ◽  
Afsaneh Mostaghasi
Keyword(s):  
Mechanical Properties ◽  
Coupling Agent ◽  
Mechanical Tests ◽  
Inorganic Nanoparticles ◽  
Nano Particles ◽  
Thermal And Mechanical Properties ◽  
Scanning Calorimetry ◽  
Nanoscale Particles ◽  
The Impact ◽  
Thermal Stability Of

The effects of titanate as a coupling agent and some particulate nanoscale particles such as TiO2, CaCO3, and ZnO on thermal and mechanical properties of emulsion polyvinylchloride (E-PVC) were investigated by thermogravimetric analysis (TGA), and mechanical tests. In this research, it was found that, in the presence of nanoparticles of CaCO3, TiO2, and ZnO, the peak temperature of dehydrochlorination of E-PVC was shifted to higher temperatures, and the rate of mass loss was decreased. Also results of differential scanning calorimetry showed that the addition of nanoparticle of CaCO3, TiO2, and ZnO led to an increase in glass transition temperature. The impact strength, elastic modulus and toughness of the samples were enhanced after addition of 0–10 part of filer in hundred parts of resin (phr) nano-CaCO3, nano-TiO2, and nano-ZnO due to improvement of compatibility of the polymer and the nano-particles. Also UV and thermal stability of the samples were enhanced by means of the nanoparticles. It was found that, in the presence of titanate as coupling agent, content of additives that could be used in the composite of PVC shifts to higher amounts.

Effect of toughened polyamide-coated carbon fiber fabric on the mechanical performance and fracture toughness of CFRP

2021 ◽  
pp. 002199832199945
Author(s):  
Jong H Eun ◽  
Bo K Choi ◽  
Sun M Sung ◽  
Min S Kim ◽  
Joon S Lee
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Photoelectron Spectroscopy ◽  
Mechanical Performance ◽  
Epoxy Composites ◽  
Scanning Calorimetry ◽  
Internal Damage ◽  
Impact Tests ◽  
Flexural Tests ◽  
The Impact

In this study, carbon/epoxy composites were manufactured by coating with a polyamide at different weight percentages (5 wt.%, 10 wt.%, 15 wt.%, and 20 wt.%) to improve their impact resistance and fracture toughness. The chemical reaction between the polyamide and epoxy resin were examined by fourier transform infrared spectroscopy, differential scanning calorimetry and X-ray photoelectron spectroscopy. The mechanical properties and fracture toughness of the carbon/epoxy composites were analyzed. The mechanical properties of the carbon/epoxy composites, such as transverse flexural tests, longitudinal flexural tests, and impact tests, were investigated. After the impact tests, an ultrasonic C-scan was performed to reveal the internal damage area. The interlaminar fracture toughness of the carbon/epoxy composites was measured using a mode I test. The critical energy release rates were increased by 77% compared to the virgin carbon/epoxy composites. The surface morphology of the fractured surface was observed. The toughening mechanism of the carbon/epoxy composites was suggested based on the confirmed experimental data.

scholarly journals Mechanical, Thermal and Rheological Properties of Polyethylene-Based Composites Filled with Micrometric Aluminum Powder

Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1242
Author(s):  
Olga Mysiukiewicz ◽  
Paulina Kosmela ◽  
Mateusz Barczewski ◽  
Aleksander Hejna
Keyword(s):  
Mechanical Properties ◽  
Melt Flow Index ◽  
Tensile Tests ◽  
Mechanical Analysis ◽  
Flow Index ◽  
Scanning Calorimetry ◽  
Metal Composites ◽  
Pre Treatment ◽  
The Impact ◽  
Properties Of Composites

Investigations related to polymer/metal composites are often limited to the analysis of the electrical and thermal conductivity of the materials. The presented study aims to analyze the impact of aluminum (Al) filler content (from 1 to 20 wt%) on the rarely investigated properties of composites based on the high-density polyethylene (HDPE) matrix. The crystalline structure, rheological (melt flow index and oscillatory rheometry), thermal (differential scanning calorimetry), as well as static (tensile tests, hardness, rebound resilience) and dynamic (dynamical mechanical analysis) mechanical properties of composites were investigated. The incorporation of 1 and 2 wt% of aluminum filler resulted in small enhancements of mechanical properties, while loadings of 5 and 10 wt% provided materials with a similar performance to neat HDPE. Such results were supported by the lack of disturbances in the rheological behavior of composites. The presented results indicate that a significant content of aluminum filler may be introduced into the HDPE matrix without additional pre-treatment and does not cause the deterioration of composites’ performance, which should be considered beneficial when engineering PE/metal composites.

scholarly journals Preparation and Characterization of Spherical Submicron CL-20 by Siphon Spray Refinement

2020 ◽  
Vol 2020 ◽  
pp. 1-9 ◽  
Author(s):  
Jiangtao Xing ◽  
Weili Wang ◽  
Wenzheng Xu ◽  
Tianle Yao ◽  
Jun Dong ◽  
...  
Keyword(s):  
Impact Sensitivity ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Crystal Forms ◽  
Refined Method ◽  
Diffraction Angle ◽  
Ultrasonic Assisted ◽  
The Impact ◽  
Thermal Stability Of

In order to improve the safety of hexanitrohexaazaisowurtzitane (CL-20), submicron CL-20 particles were prepared by a siphon ultrasonic-assisted spray refining experimental device. The samples were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and differential scanning calorimetry (DSC), and the impact sensitivity of the samples was tested. The results show that the particle size of siphon-refined CL-20 is about 800 nm~1 μm, which is more smooth, mellow, and dense than that of CL-20 prepared by a traditional pressure-refined method. The peak diffraction angle of pressure- and siphon-refined CL-20 is basically the same as that of raw CL-20, and their crystal forms are ε type. The peak strength of pressure- and siphon-refined CL-20 decreased obviously. The apparent activation energy of pressure-refined CL-20 and siphon-refined CL-20 is 13.3 kJ/mol and 11.95 kJ/mol higher than that of raw CL-20, respectively. The thermal stability of CL-20 is improved. The activation enthalpy (ΔH#) is significantly higher than that of raw CL-20, and the characteristic drop is 70.4% and 82.7% higher than that of raw CL-20. The impact sensitivity of siphon-refined CL-20 is lower than that of pressure-refined CL-20, so the safety performance of an explosive is improved obviously.

scholarly journals Characteristics and mechanical properties changes due to incorporation of aloe vera in polyethylene-based film

2020 ◽  
Vol 17 (2) ◽  
pp. 61
Author(s):  
Siti Fatma Abd Karim ◽  
Junaidah Binti Jai ◽  
Ku Halim Ku Hamid ◽  
Abdul Wafi Abdul Jalil
Keyword(s):  
Mechanical Properties ◽  
Thermal Degradation ◽  
Aloe Vera ◽  
Functional Materials ◽  
Chain Structure ◽  
Substantial Effect ◽  
Scanning Calorimetry ◽  
Degradation Temperature ◽  
And Performance ◽  
The Impact

Non-degradable properties of polyethylene (PE) films due to long-chain structure cause increment of solid waste plastic. Many researchers, with different purposes, have studied the incorporation of functional materials to PE. Studying the impact of incorporation of aloe vera (AV) into PE films in terms of its characteristic and mechanical properties is the main objective of this paper. The films were prepared using melt-blending and hot press technique. The characterization assessed for the PE and PE-AV films were spectroscopy, crystalline phase, thermal analysis and performance of mechanical properties of the sample.  The functional group detected in spectroscopy studied did not show any changes for PE film or PE with the presence of AV. Lower thermal degradation temperature (Td) obtained for PE-AV3 while others film found no significant changes of Td value and only one peak of thermal degradation occurred for all film. The same goes to the analysis obtained from differential scanning calorimetry (DSC) data. However, the crystalline structure displayed momentous peak changes for PE with AV. The highest tensile strength (TS) obtained by PE-AV3, at once developing highest value of Young’s modulus (YM), modulus of resilience (UE) and modulus of toughness (UT). A certain amount of AV has substantial effect on changing the polymeric structure especially improving the mechanical properties of PE film. Therefore, AV has potential to become an additive for developing a new partially degradable PE film.

The Structure and Mechanical Properties of Plastically Consolidated Al-Ni Alloy

2016 ◽  
Vol 682 ◽  
pp. 245-251 ◽  
Author(s):  
Grzegorz Włoch ◽  
Tomasz Skrzekut ◽  
Jakub Sobota ◽  
Antoni Woźnicki ◽  
Justyna Cisoń
Keyword(s):  
Mechanical Properties ◽  
Vickers Hardness ◽  
Tensile Tests ◽  
Mechanical Analysis ◽  
Intermetallic Phases ◽  
Scanning Calorimetry ◽  
Porosity Formation ◽  
X Ray ◽  
Ni Alloy ◽  
Thermal Stability Of

Mixed and preliminarily consolidated powders of aluminium and nickel (90 mass % Al and 10 mass % Ni) were hot extruded. As results the rod, 8 mm in diameter, was obtained. As-extruded material was subjected to the microstructural investigations using scanning electron microscopy (SEM/EDS) and X-ray analysis (XRD). The differential scanning calorimetry (DSC) and thermo-mechanical analysis (TMA) were also performed. The mechanical properties of as extruded material were determined by the tensile test and Vickers hardness measurements. In order to evaluate the thermal stability of PM alloy, samples were annealed at the temperature of 475 and 550 °C. After annealing Vickers hardness measurements and tensile tests were carried out. The plastic consolidation of powders during extrusion was found to be very effective, because no pores or voids were observed in the examined material. The detailed microstructural investigations and XRD analyses did not reveal the presence of the intermetallic phases in the as-extruded material. During annealing, the Al3Ni intermetallic compound was formed as the result of chemical reaction between the alloy components. The hardness of the alloy after annealing at the temperature of 475°C was found to be comparable to the hardness in as-extruded state. Annealing of the material at the temperature of 550°C results in hardness decreasing by about 50%, as the consequence of porosity formation and Al3Ni cracking.

Modification of Polylactic Acid/ Halloysite Bionanocomposites Using Electron Beam Radiation: Physical, Barrier and Thermal Properties

2020 ◽  
Vol 1002 ◽  
pp. 57-65
Author(s):  
Abdulkader M. Alakrach ◽  
Nik Noriman Zulkepli ◽  
Awad A. Al-Rashdi ◽  
Sam Sung Ting ◽  
Rosniza Hamzah ◽  
...  
Keyword(s):  
Electron Beam ◽  
Polylactic Acid ◽  
Food Packaging ◽  
Electron Beam Irradiation ◽  
Casting Process ◽  
Barrier Properties ◽  
Beam Irradiation ◽  
Beam Radiation ◽  
Electron Beam Processing ◽  
The Impact

This study aimed to develop novel Polylactic acid/ Halloysite (PLA/ HNTs) films which showed better properties when they were used for food packaging. They also displayed better mechanical, barrier, morphological and structural properties when the researchers analysed the impact of the electron beam irradiation on the nanomaterials. They prepared PLA-based nanocomposites containing 5 % w/w of HNTs using the solution casting process. These nanocomposites were further exposed to different ebeam doses (i.e., 0, 20, 40 and 60 kGy). The researchers assessed the effect of the electron beam irradiation on the various properties of the PLA. All the composites showed a homogenous dispersion and distribution of the HNTs in this PLA matrix. Results indicated that the nanocomposites showed better barrier properties in comparison to the neat PLA. Furthermore, the ebeam irradiation could increase the glass-transition temperature and lead to the development of more crosslinks, which increased the degradation temperature and hydrophilicity of the nanocomposites. In this study, the researchers showed that the PLA/HNTs films were effective materials that could be used for the electron beam processing of the pre-packed foods. The best effect was noted for the 20 kGy dosage which was used in the study.

scholarly journals The Effects of Silica-Based Fillers on the Properties of Epoxy Molding Compounds

Materials ◽  
2019 ◽  
Vol 12 (11) ◽  
pp. 1811 ◽  
Author(s):  
Mitja Linec ◽  
Branka Mušič
Keyword(s):  
Mechanical Properties ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Fused Silica ◽  
Spiral Flow ◽  
Scanning Calorimetry ◽  
Molding Compounds ◽  
Material Development ◽  
The Impact

Global design and manufacturing of the materials with superb properties remain one of the greatest challenges on the market. The future progress is orientated towards researches into the material development for the production of composites of better mechanical properties to the existing materials. In the field of advanced composites, epoxy molding compounds (EMCs) have attained dominance among the common materials due to their excellent properties that can be altered by adding different fillers. One of the main fillers is often based on silicon dioxide (SiO2). The concept of this study was to evaluate the effects of the selected silica-based fillers on the thermal, rheological, and mechanical properties of EMCs. Various types of fillers with SiO2, including crystalline silica and fused silica, were experimentally studied to clarify the impact of filler on final product. Fillers with different shape (scanning electron microscope, SEM), along with different specific surface area (specific surface area analyzer, BET method) and different chemical structure, were tested to explore their modifications on the EMCs. The influence of the fillers on the compound materials was determined with the spiral flow length (spiral flow test, EMMI), glass transition temperature (differential scanning calorimetry, DSC), and the viscosity (Torque Rheometer) of the composites.

scholarly journals Bio-Based Packaging Materials Containing Substances Derived from Coffee and Tea Plants

Materials ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 5719
Author(s):  
Olga Olejnik ◽  
Anna Masek
Keyword(s):  
Mechanical Properties ◽  
Caffeic Acid ◽  
Green Tea ◽  
Chemical Structure ◽  
Green Tea Extract ◽  
Packaging Materials ◽  
Scanning Calorimetry ◽  
Spectra Analysis ◽  
Tea Extract ◽  
The Impact

The aim of the research was to obtain intelligent and eco-friendly packaging materials by incorporating innovative additives of plant origin. For this purpose, natural substances, including green tea extract (polyphenon 60) and caffeic acid, were added to two types of biodegradable thermoplastics (Ingeo™ Biopolymer PLA 4043D and Bioplast GS 2189). The main techniques used to assess the impact of phytocompounds on materials’ thermal properties were differential scanning calorimetry (DSC) and thermogravimetry (TGA), which confirmed the improved resistance to thermo-oxidation. Moreover, in order to assess the activity of applied antioxidants, the samples were aged using a UV aging chamber and a weathering device, then retested in terms of dynamic mechanical properties (DMA), colour changing, Vicat softening temperature, and chemical structure, as studied using FT-IR spectra analysis. The results revealed that different types of aging did not cause significant differences in thermo-mechanical properties and chemical structure of the samples with natural antioxidants but induced colour changing. The obtained results indicate that polylactide (PLA) and Bioplast GS 2189, the plasticizer free thermoplastic biomaterial containing polylactide and starch (referred to as sPLA in the present article), both with added caffeic acid and green tea extract, can be applied as smart and eco-friendly packaging materials. The composites reveal better thermo-oxidative stability with reference to pure materials and are able to change colour as a result of the oxidation process, especially after UV exposure, providing information about the degree of material degradation.

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