scholarly journals Biostability of synthetic polymer materials – polyethylene, polypropylene and polycarbonate – in the conditions of Surgut

2021 ◽  
Vol 10 (1) ◽  
pp. 107-112
Author(s):  
Maria Viktorovna Mantrova
Keyword(s):  
Podzolic Soil ◽  
Synthetic Polymer ◽  
Polymer Materials ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Polyethylene Pipes ◽  
Alkaline Reaction ◽  
Different Types ◽  
Polyethylene Sample ◽  
Typical Soil

The paper is devoted to the study of biostability of polyethylene, polypropylene and polycarbonate in the conditions of Surgut after their presence within a year in different types of soils swamp-podzolic soil, culturosem and urbanozem. The studied types of soils differ in their chemical composition urbanozems are saturated with bases, have a slightly alkaline reaction, they also contain an excess of lead content due to their close location to highways. In the studied soils bacterial microflora prevails over mycoflora, the amount of heterotrophic and lithoautotrophic microflora in urbanozems is especially high, which is due to the high anthropogenic load on these soils. For seeds and seedlings of wheat and radish the stimulating effect of these soils was revealed. Micromycetes isolated from the surface of polypropylene and polyethylene pipes are typical soil saprotrophs that can act as biodestructors of polymers. In the field experiment all the materials under study are biostable, and there was a slight change in the color of the cross-linked polyethylene sample. In the laboratory experiment certain instability of all the materials under study was revealed; their gradation in terms of mushroom resistance (from resistant to unstable) is as follows: low-density polyethylene, polypropylene random-heat-resistant copolymer, polycarbonate, cross-linked polyethylene. The nature of damage to low-density polyethylene (polyethylene film) is superficial, which corresponds to the literature data.

scholarly journals Effect of Heat Drawing Process on Mechanical Properties of Dry-Jet Wet Spun Fiber of Linear Low Density Polyethylene/Carbon Nanotube Composites

2017 ◽  
Vol 2017 ◽  
pp. 1-9
Author(s):  
Jong Won Kim ◽  
Joon Seok Lee
Keyword(s):  
Mechanical Properties ◽  
Plastic Deformation ◽  
Tensile Strength ◽  
Polymer Materials ◽  
Degree Of Crystallinity ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Drawing Process ◽  
Linear Low Density Polyethylene ◽  
Crystallinity Degree

Polyethylene is one of the most commonly used polymer materials. Even though linear low density polyethylene (LLDPE) has better mechanical properties than other kinds of polyethylene, it is not used as a textile material because of its plastic behavior that is easy to break at the die during melt spinning. In this study, LLDPE fibers were successfully produced with a new approach using a dry-jet wet spinning and a heat drawing process. The fibers were filled with carbon nanotubes (CNTs) to improve the strength and reduce plastic deformation. The crystallinity, degree of orientation, mechanical properties (strength to yield, strength to break, elongation at break, and initial modulus), electrical conductivity, and thermal properties of LLDPE fibers were studied. The results show that the addition of CNTs improved the tensile strength and the degree of crystallinity. The heat drawing process resulted in a significant increase in the tensile strength and the orientation of the CNTs and polymer chains. In addition, this study demonstrates that the heat drawing process effectively decreases the plastic deformation of LLDPE.

Space Charge Studies in XLPE from Power Cables Using Combined Isothermal and Thermostimulated Current Measurements

2006 ◽  
Vol 514-516 ◽  
pp. 935-939
Author(s):  
M. Carmo Lança ◽  
Eugen R. Neagu ◽  
Len A. Dissado ◽  
José N. Marat-Mendes
Keyword(s):  
High Temperature ◽  
Space Charge ◽  
Relaxation Times ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Power Cables ◽  
Combined Procedure ◽  
Field Temperature ◽  
Different Types ◽  
Different Sources

Cross-linked polyethylene (XLPE) peelings from aged power cables from three different sources were studied using a combined procedure of isothermal and thermo-stimulated current measurements. Different parameters, such as electric field, temperature, charging/discharging times, can be selected in order to make an analysis of the space charge characteristics (such as, relaxation times and activation energies). Three different cables peelings were analyzed: A – electrically aged in the laboratory at high temperature, B – service aged for 18 years and C – thermally aged in the laboratory at high temperature. The results were compared for the different types of samples and also with previous results on laboratory aged and produced films of low-density polyethylene (LDPE) and XLPE.

scholarly journals Modelling the conduction mechanisms in low density polyethylene material using finite element method

2021 ◽  
Vol 63 (1) ◽  
pp. 27-33
Author(s):  
Mai Quyen Hoang ◽  
◽  
Thi Thu Nga Vu ◽  
Manh Quan Nguyen ◽  
Severine Le Roy ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Charge Transport ◽  
Transport Model ◽  
Polymer Materials ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Original Design ◽  
Conduction Mechanisms ◽  
Element Method

Polymers used as insulating materials are increasingly popular in many different fields. In electrical engineering - electronics, polymers are used in high-voltage transmission cables, capacitors, transformers, or as part of an embedded system in the IGBT module thanks to its superior thermal and electrical insulation properties. One of the disadvantages of polymers is the possible accumulation of space charge in the material volume for a long time, leading to an increase in the electric field compared to the original design value. Charge transport models in polymer materials have been increasingly developed to predict the conduction mechanisms under thermal-electrical stress. In this study, from a finite volume method (FVM), the authors developed a charge transport model in low density polyethylene (LDPE) based on the finite element method (FEM). The simulation results of this model are also compared to experimental results and to the FVM model under different electric fields for LDPE.

The behaviour of the oxo-biodegradable LDPE materials during the service life

2012 ◽  
Vol 23 (2) ◽  
pp. 187-190
Author(s):  
Corina Teodorescu ◽  
Lica Mitrana ◽  
Anca-Corina Teiu
Keyword(s):  
Mechanical Properties ◽  
Service Life ◽  
Polymer Films ◽  
Metal Content ◽  
Synthetic Polymer ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Soil Columns ◽  
Short Life ◽  
Polyethylene Films

AbstractThis is an experimental study on behaviour of oxo-biodegradable plastics containing additives during service life. Low density polyethylene is a most extensive used synthetic polymer with the largest production, because an important part of the production is converted into various products with short life cycle. The goal of this paper was to quantify the biodegradation of two low density polyethylene films containing 10% and 20% pro-oxidant AddiFlex in soil columns. Previously, the physical-mechanical properties and heavy metal content in polymer films have been determined. The obtained degree of mineralization was around 60% after 200 days of incubation for both studied polymer films (59.8% for 10% additive and 64.3% for 20% additive).

scholarly journals Comparative Morphological Investigation between Natural Photo-Aged of Two Different Low Density Polyethylene Green House Covers

2021 ◽  
Vol 8 (1) ◽  
pp. 1-4
Author(s):  
BabaghayouMeriam Imane ◽  
AbdelHamid Ismail Mourad
Keyword(s):  
Degree Of Crystallinity ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Natural Ageing ◽  
Dsc Analysis ◽  
Polyethylene Films ◽  
Extruded Films ◽  
Different Types ◽  
Degradation Behaviors ◽  
Better Than

This work studies and compares the degradation performance of two different types of blown extruded films of low density polyethylene films used as greenhouse covers. The first one is LDPE (B24/2) supplied by ENIP Skikda and the other one is LDPE (2100 T N00W) supplied by SABIC, Saudi Arabia. Both films are commonly used in Algeria as greenhouse covers. The films were exposed outdoors over a period of 8 months for natural ageing. XRD and DSC analysis were conducted to characterize the thermal properties of the materials and compare between their degradation behaviors. The results revealed that the degradation resistance of LDPE (B24/2) is better than LDPE (2100T N00W) in term of their degree of crystallinity. Keywords: Natural Ageing, LDPE (B24/2); LDPE (2100 T N00W); Degree of Crystallinity, XRD; DSC.

scholarly journals Investigating the Plastic Decomposing Ability of Tenebriomolitor Using Carbon Dioxide Sensors

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Xiangrong Huang ◽  
◽  
Yueyi Li ◽  
Kenneth Y T Lim ◽  
◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Polyvinyl Chloride ◽  
Carbon Dioxide Concentration ◽  
High Density ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Carbon Dioxide Sensors ◽  
Different Types ◽  
Darkling Beetles ◽  
The Difference

According to a group of Stanford scientists, mealworms, the larva of darkling beetles, can digest Styrofoam, a type of polystyrene, and break it down into carbon dioxide. This paper investigates the plastic-digesting property of mealworms on different types of plastic, namely polystyrene (PS), low- density polyethylene (LDPE) and polyvinyl chloride (PVC). Since mealworms breathe in oxygen and exhale carbon dioxide. To measure the extent of plastic intake, we explored an alternative method to measure the extent of plastic digestion - using Arduino carbon dioxide sensors instead of calculating the difference in weight of plastic. As the increase in the exhalation of carbon dioxide is indicative of the amount of plastic consumed, the authors measured the change in carbon dioxide concentration of the mealworms' environment as they consume plastic. This is put into comparison with when the mealworms respire without food. The results show that mealworms consume Styrofoam to a certain extent. However, they are mostly unable to digest polyethylene and polyvinyl chloride, likely due to their elasticity and high density respectively.

scholarly journals Boron Nitride-Filled Linear Low-Density Polyethylene for Enhanced Thermal Transport: Continuous Extrusion of Micro-Textured Films

Polymers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 3393
Author(s):  
Özgün Güzdemir ◽  
Sagar Kanhere ◽  
Victor Bermudez ◽  
Amod A. Ogale
Keyword(s):  
Thermal Conductivity ◽  
Boron Nitride ◽  
Surface Area ◽  
Thermal Transport ◽  
Polymer Materials ◽  
Low Density Polyethylene ◽  
Packaging Materials ◽  
Low Density ◽  
Linear Low Density Polyethylene ◽  
Continuous Extrusion

With shrinking size of electronic devices, increasing performance and accompanying heat dissipation, there is a need for efficient removal of this heat through packaging materials. Polymer materials are attractive packaging materials given their low density and electrical insulating properties, but they lack sufficient thermal conductivity that inhibits heat transfer rate. Hexagonal boron nitride (BN) possesses excellent thermal conductivity and is also electrically insulating, therefore BN-filled polymer composites were investigated in this study. Results showed successful continuous extrusion of BN-filled linear low-density polyethylene through micro-textured dies that is a scalable manufacturing process. Through-thickness thermal conductivity measurements established that 30 vol% BN content led to an over 500% increase in thermal conductivity over that of pure polymer. Textured film surface provided about a 50% increase in surface area when compared with non-textured films. This combination of increased surface area and enhanced thermal conductivity of BN-filled textured films indicates their potential application for improved convective thermal transport.

scholarly journals Eco-friendly polymer materials for agricultural purposes

2019 ◽  
Vol 298 ◽  
pp. 00130
Author(s):  
Mariya Podzorova ◽  
Yulia Tertyshnaya ◽  
Anatoly Popov
Keyword(s):  
Water Absorption ◽  
Synthetic Polymers ◽  
Polymer Materials ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Absorption Kinetics ◽  
Polyethylene Blends ◽  
The Impact ◽  
Soil Changes ◽  
Soil And Water

The paper deals with various polymer materials for agricultural purposes. To date, there are many technologies for growing crops that use polymer films: greenhouses, greenhouses, planting seeds in capsules. There are a lot of works on the study of biodegradable compositions based on biopolymers with synthetic polymers, as well as the analysis of the impact of destructive environmental factors on samples. Binary polylactide–low-density polyethylene blends of various compositions were prepared, and their biodegradability in soil and water absorption kinetics. The degree of water absorption is higher for the blends than for the pure polymers. The weight loss is higher upon incubation in laboratory soil compared to open soil. Changes in the specimen macrostructure after exposure to soil were demonstrated by optical microscopy.

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