Regularities of changes in the properties of multilayer  polymer films depending on their structure

The physical-mechanical, optical and operational properties of three types of multilayer polymer films that are used in the manufacture of laminates for food packaging and differ in the composition and number of layers (from 3 to 9) are studied: transparent based on high-pressure polyethylene; white (containing a white pigment) on the basis of high pressure polyethylene; transparent barrier based on high-pressure polyethylene, polyamide and ethylene copolymer with vinyl alcohol. For comparison, we also used a single-layer film made of high-pressure polyethylene. The films were tested for tensile strength, resistance to delamination of the welded joint, spectral transmittance, optical density, differential scanning calorimetry curves were registered, and gas permeability was determined. To assess the light aging, the film samples were irradiated with a source of ultraviolet light. The following regularities are revealed: the tensile strength of the studied films does not differ significantly, both when changing their composition and the number of layers; a threefold increase in the number of layers leads to a noticeable increase in the elastic modulus of films made of high-pressure polyethylene with a white pigment; barrier film has a higher modulus of elasticity than transparent films based on high-pressure polyethylene; the resistance to delamination of the welded joint increases in the presence of high-pressure polyethylene films with the same number of layers of white pigment and increasing their thickness; increasing the number of layers leads to a decrease in the spectral transmittance and light resistance of transparent films, but does not affect this indicator of films with white pigment; the role of white pigment as an ultraviolet light absorber causes the greatest light resistance of films and its lesser dependence on the number of layers; barrier film in terms of light transmission and resistance to light aging is inferior to transparent films based on high-pressure polyethylene, but it is significantly superior to a single-layer film; the gas permeability of barrier films naturally decreases with increasing thickness, and after light aging significantly increases due to photo-oxidative degradation of polymer layers and, to a greater extent, the layer of ethylene with vinyl alcohol copolymer.

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Properties of nanocomposites based on isotactic polypropylene and high-pressure polyethylene with metal-containing nanofillers

Perspektivnye Materialy ◽

10.30791/1028-978x-2020-9-59-64 ◽

2020 ◽

pp. 59-64

Author(s):

N. I. Kurbanova ◽

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T. M. Gulieva ◽

N. Ya. Ischenko ◽

◽

...

Keyword(s):

High Pressure ◽

Synergistic Effect ◽

Polymer Matrix ◽

Isotactic Polypropylene ◽

Rheological Parameters ◽

Mechanochemical Method ◽

X Ray ◽

Effect Of Additives ◽

High Pressure Polyethylene ◽

Properties Of Composites

The effect of additives of nanofillers (NF) containing nanoparticles (NP) of copper oxide, stabilized by a polymer matrix of maleized polyethylene (MPE), obtained by the mechanochemical method, on the properties of composites based on isotactic polypropylene (PP) and high-pressure polyethylene (PE) was studied by X-ray phase (XRD) and thermogravimetric (TGA) analyzes. The enhancement of strength, deformation, and rheological parameters, as well as the thermo-oxidative stability of the obtained nanocomposites was revealed, which, apparently, is due to the synergistic effect of the interaction of copper-containing nanoparticles with anhydride groups of MPE. It is shown that nanocomposites based on PP/PE/NF can be processed both by pressing and injection molding and extrusion, which expands the scope of its application.

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Change in the structure and properties of high pressure polyethylene during ozone oxidation. Effect of orientation and strain

Polymer Science U S S R ◽

10.1016/0032-3950(90)90396-n ◽

1990 ◽

Vol 32 (4) ◽

pp. 732-736

Author(s):

S.G Karpova ◽

A.V Russak ◽

A.A Popov ◽

G.E Zaikov

Keyword(s):

High Pressure ◽

Structure And Properties ◽

Ozone Oxidation ◽

High Pressure Polyethylene ◽

Oxidation Effect

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Sol-Gel Derived Titaniajormosil Composite Thin Films For Optical Waveguide Applications

MRS Proceedings ◽

10.1557/proc-576-427 ◽

1999 ◽

Vol 576 ◽

Author(s):

Wenxiu Que ◽

Y. Zhou ◽

Y. L. Lam ◽

Y. C. Chan ◽

S. D. Cheng ◽

...

Keyword(s):

Sol Gel ◽

Single Layer ◽

Titanium Content ◽

Gravimetric Analysis ◽

Force Microscopy ◽

Free Film ◽

Free Silica ◽

Atomic Force ◽

Bonding Properties ◽

Single Layer Film

ABSTRACTWe report the preparation of sol-gel waveguide films based on a newly developed recipe to incorporate organic molecules into the inorganic sol-gel glass matrix. The film was derived from a sol that has a higher titanium content in an organically modified silane (ORMOSIL), namely, ÿ-Glycidoxypropyltrimethoxysilane. We have shown that using spin-coating and low temperature baking, a single coating layer can have a thickness of more than 1.5 μm. When such a single layer film is deposited on a microscope glass slide or a piece of silicon with a buffercladding layer, it is able to support the guiding of optical waves. We have characterized the film using scanning electron microscopy, atomic force microscopy, X-ray diffractometry, thermal gravimetric analysis. differential thermal analysis and Fourier transform infrared spectroscopy and have studied the properties of the waveguide film, including the microstructural properties. the chemical bonding properties, and the optical properties. Based on these experimental results, we found that a heat-treatment at a temperature slightly below 200°C is necessary to attain a dense pore-free film. It has also been noted that a purely inorganic and crack-free silica-titania film can be obtained after baking the titania-ORMOSIL composite film at 500°C or higher.

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Plasmon modes in N-layer silicene structures

Journal of Physics Condensed Matter ◽

10.1088/1361-648x/ac3c66 ◽

2021 ◽

Author(s):

Men Nguyen Van

Keyword(s):

Electric Field ◽

Random Phase ◽

Single Layer ◽

Plasmon Mode ◽

Orbit Coupling ◽

Collective Excitations ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Number Of Layers ◽

Plasmon Modes

Abstract We investigate the plasmon properties in N-layer silicene systems consisting of N, up to 6, parallel single-layer silicene under the application of an out-of-plane electric field, taking into account the spin-orbit coupling within the random-phase approximation. Numerical calculations demonstrate that N undamped plasmon modes, including one in-phase optical and (N-1) out-of-phase acoustic modes, continue mainly outside the single-particle excitation area of the system. As the number of layers increases, the frequencies of plasmonic collective excitations increase and can become much larger than that in single layer silicene, more significant for high-frequency modes. The optical (acoustic) plasmon mode(s) noticeably (slightly) decreases with the increase in the bandgap and weakly depends on the number of layers. We observe that the phase transition of the system weakly affects the plasmon properties, and as the bandgap caused by the spin-orbit coupling equal that caused by the external electric field, the plasmonic collective excitations and their broadening function in multilayer silicene behave similarly to those in multilayer gapless graphene structures. Our investigations show that plasmon curves in the system move toward that in single layer silicene as the separation increases, and the impacts of this factor can be raised by a large number of layers in the system. Finally, we find that the imbalanced carrier density between silicene layers significantly decreases plasmon frequencies, depending on the number of layers.

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Stacked Microchannel Heat Sinks for Liquid Cooling of Microelectronic Components

10.1115/imece2000-1537 ◽

2000 ◽

Author(s):

X. Wei ◽

Y. Joshi

Keyword(s):

Flow Rate ◽

Heat Sink ◽

Water Flow Rate ◽

Heat Removal ◽

Single Layer ◽

Heat Sinks ◽

Computationally Efficient ◽

Liquid Cooling ◽

Number Of Layers ◽

Microelectronic Components

Abstract A novel heat sink based on a multi-layer stack of liquid cooled microchannels is investigated. For a given pumping power and heat removal capability for the heat sink, the flow rate across a stack of microchannels is lower compared to a single layer of microchannels. Numerical simulations using a computationally efficient multigrid method [1] were carried out to investigate the detailed conjugate transport within the heat sink. The effects of the microchannel aspect ratio and total number of layers on thermal performance were studied for water as coolant. A heat sink of base area 10 mm by 10 mm with a height in the range 1.8 to 4.5 mm (2–5 layers) was considered with water flow rate in the range 0.83×10−6 m3/s (50 ml/min) to 6.67×10−6 m3/s (400 ml/min). The results of the computational simulations were also compared with a simplified thermal resistance network analysis.

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An overview of deep learning techniques

at - Automatisierungstechnik ◽

10.1515/auto-2018-0076 ◽

2018 ◽

Vol 66 (9) ◽

pp. 690-703 ◽

Cited By ~ 1

Author(s):

Michael Vogt

Keyword(s):

Deep Learning ◽

Single Layer ◽

Visual Image ◽

Image Understanding ◽

Number Of Layers ◽

Box Models ◽

Learning Techniques ◽

Engineering Work ◽

Computational Resources ◽

Black Box Models

Abstract Deep learning is the paradigm that profoundly changed the artificial intelligence landscape within only a few years. Although accompanied by a variety of algorithmic achievements, this technology is disruptive mainly from the application perspective: It considerably pushes the border of tasks that can be automated, changes the way products are developed, and is available to virtually everyone. Subject of deep learning are artificial neural networks with a large number of layers. Compared to earlier approaches with ideally a single layer, this allows using massive computational resources to train black-box models directly on raw data with a minimum of engineering work. Most successful applications are found in visual image understanding, but also in audio and text modeling.

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