bluuebunny/crossref_metadata_2025 huggingface dataset:
Foaming of Polymer Blends – Chance and Challenge
Authors: Ruckdäschel Holger , Altstädt Volker , Müller Axel H.E.
Published: September 2018

The foaming behaviour of polymer blends was systematically investigated using carbon dioxide as a blowing agent. Two batch-processing techniques were used to prepare specimens of different size. Various binary mixtures over a wide compositional range were selected as reference materials, in particular including immiscible (poly(2,6-dimethyl-1,4-phenylene ether)/poly(styrene-co-acrylonitrile) (PPE/SAN) blends. Moreover, the influence of a compatibilization with block copolymers was investigated for PPE/SAN blends. The resulting foam morphology was characterised by evaluating the density, the cell size distribution, the cell wall morphology and the compression behaviour. Besides the commonly accepted key criteria for foaming neat polymers, our study identified significant factors determining the foamability of blends such as the blend morphology, the rheological and the thermal properties. Interestingly, the compatibilization of these PPE/SAN blends by block copolymers was identified as a technique to establish micro- and submicrocellular foam morphologies with nanostructured cell walls. In view of these results, new pathways for the tailoring of cellular materials are derived.
Crosslinking of Polyolefin Foam II. Applicability of Parameters to Assess Crosslinking/Foam Density Relationships
Authors: Sipaut C.S. , Sims G.L.A. , Ariff Z.M.
Published: September 2018

The effect of introducing triallyl cyanurate (TAC) monomer, into dicumyl peroxide (DCP) crosslinking systems for low-density polyethylene (LDPE) is considered. In the foam formation, chemical blowing used in a fixed amount of 8.0 phr. Effects are characterised as a function of relative concentrations in solid, melt and foamed states. It was observed that gel content could only be used as a reasonable indicator to predict foaming behaviour only for traditional crosslinking with DCP alone. The results also showed that melt modulus seemed a better indicator when TAC was incorporated in the system but appeared only to be particularly relevant at a specific TAC concentration. It was found that swell ratio better controls expansion prediction whereas foam density determines physical and mechanical properties independent of formulation. Moreover, swell ratio appeared to be able to define expansion characteristics not only of traditional crosslinking systems but also those containing triallyl cyanurate monomer.
Extrusion Foam Coating of Coaxial Cables using Chemical Blowing Agent
Authors: Marvian M. Nazari , Behravesh A.H. , Golzar M.
Published: September 2018

This paper presents an experimental study on manufacture and characterization of an insulating foam coating in the coaxial cables. Coaxial cables with foam insulator are widely used in the communication industries; low loss attenuation coaxial cable is used in the feeders of base stations for mobile phones. The insulating foam plays a principle role in the attenuation characteristics of the cable. In this research work, an extrusion setup was prepared to produce foam insulated coaxial cable where a chemical blowing agent was used as the foaming agent. The effects of blowing agent and die outlet diameter on foam density and loss-attenuation were investigated. The results show that an acceptable loss-attenuation is achievable via adjusting processing parameters.
A Summary of Work Carried out by EUROPUR into Extractable Materials from Flexible Polyurethane Foam
Authors: Hillier K. , King D.A.
Published: September 2018

The European polyurethane flexible slabstock manufacturing trade association, EUROPUR, has carried out extensive analytical work over recent years to determine if any extractable or volatile materials can be detected emanating from PU foam. Much of this work concerning aromatic amines and VOCs has already been published. This brief review summarises other work, which has been carried out during this research period.
Cleanroom Insulation Performance of Nitrogen Expanded Low Density Polyvinylidene Fluoride (PVDF) Foams
Authors: Witten Neil
Published: September 2018

Zotefoams plc is a world leading manufacturer of low density, closed-cell, crosslinked block foams and is recognised globally for producing the highest performance polyolefin foams. In recent years the company has developed a new generation of low density foams based on materials where foaming has traditionally been an insurmountable technical challenge or other limitations have existed to the reduction in density possible.

One of these new commercially available foam products, sold under the trademark ZOTEK® F, is based on the fluoropolymer Polyvinylidene Fluoride (PVDF). The properties of the products, not surprisingly, reflect the general properties of the fluoropolymer family however as cellular materials the combination of material attributes is unsurpassed in the industry.

This paper will describe these novel foam products covering the key aspects of the current commercial grades of ZOTEK® F and the technology used to manufacture them. The paper will then focus on a specific application area in cleanroom insulation, where the product performance will be reviewed against the combination of technically challenging requirements such as low flammability, low smoke generation, low thermal conductivity, low moisture absorption, chemical inertness and resistance to fungal growth.
The Cross-Lagged Relations Between Teacher-Student Relatedness and Reading Achievement of Academically At-Risk Students
Authors: Caleon Imelda S. , Wui Ma. Glenda L.
Published: September 2018

This two-wave study examined the cross-lagged relations between teacher-student relatedness (student-teacher communication, teacher trust, and teacher alienation) and reading achievement of academically at-risk secondary students ( N = 787) in Singapore. Compared with the cohort, these students had lower aggregate scores in a national examination administered at Grade 6. The results of the study showed that teacher trust at T1 (Grade 7) served as a positive predictor while student-teacher communication at T1 served as a negative predictor of reading achievement at T2 (Grade 8), after controlling for reading achievement at T1, gender, and general cognitive ability. Reading achievement at T1 was found to be a negative predictor of all dimensions of teacher-student relatedness, except teacher trust, at T2, even after accounting for the effects of teacher-student relatedness at T1, gender, and general cognitive ability. The results of the study reflect the complexity of the relationship between students’ academic achievement and teacher-student relatedness.
Simulation of Warpage Behaviour of Pur Sandwich Structures
Authors: Haberstroh E. , Kleba I.
Published: September 2018

PUR sandwich construction is used for the inexpensive production of lightweight, rigid and decorated parts in one operation. Depending upon the type of sandwich construction, however, warpage of the parts may occur (e.g. in the case of in-mould decorated parts); this is counteracted in industry by means of cost-intensive pilot investigations and the use of form gauges. Against this background, a mathematical model was produced of the warpage behaviour of PUR sandwich structures of this type and the FEA algorithm developed verified using a warpage analysis of parts with a simple geometry. The conclusion reached is that PUR processors may be provided with a computer simulation which will enable them to estimate the warpage and identify compensatory measures as early as the construction phase.
Improved Adhesion of Plastics by Gas-Phase Fluoridation
Authors: Krüger G.
Published: September 2018

Plastics with a low surface energy can be firmly bonded together after gas-phase fluoridation. Gasification with a fluorine/nitrogen mixture considerably improves the wettability and adhesion of glues. The effect of this method of pre-treatment was proven with amorphous PET, PP without primers and NR, CR and EPM with different glues. Unlike other industrial pre-treatment methods, gas-phase fluorination may be performed by subcontractors, as the activation state is not limited by time.
Continuous Recycling of Vulcanisates
Authors: Fukumori K. , Mouri M. , Sato N. , Okamoto H. , Matsushita M.
Published: September 2018

Vulcanised EPDM rubber waste produced during the manufacturing process is devulcanised using a screw granulator under controlled conditions of shear stress, temperature and internal stress. During this recycling process, carbon-sulphur bonds are broken selectively so that a devulcanised rubber consisting of a sol component and a gel component is obtained which can be processed like new rubber and re-vulcanised with an accelerated sulphur curing system. The revulcanisates exhibit nearly the same properties as cured new rubber. EPDM rubber which has been devulcanised using the new process is used for the production of rubber products for the automobile industry.
Welding of Crosslinked Polyethylene Pipes
Authors: Tobias W.
Published: September 2018

The butt-welding of pipes made of crosslinked polyethylene, the most efficient joining method for the material PE-X, which up to now has been regarded an ‘non-weldable’, will enable it to be used for industrial and underground pipes and hence will make a major contribution to state-of-the-art and future-orientated pipeline applications.

In the future, it should also be possible to weld PE-X pipes with diameters of less than 90 mm and work is also being performed to develop welded joints with the same temperature resistance as the pipes. This will permit the use of welded PE-X pipes for hot-water systems and heating technology.
Characterisation of the Surface Activity of Carbon Blacks
Authors: Schröder A. , Meier J. , Klüppel M. , Schuster R.H.
Published: September 2018

In order to gain a better understanding of the reinforcement mechanism of fillers, the surface activity of a selection of industrial carbon blacks produced by different procedures with varying average particle sizes (spec. N2 surface area) and aggregate structure (DBP number) were investigated using the volumetric gas adsorption method. The adsorption isotherms for polymer-like gases were used to determine the particles’ geometrical surface roughness and the distribution functions of energetically different bonding sites for polymers on the surfaces on atomic length scales. The influence of the surface activity on the reinforcement of elastomers is demonstrated using examples of vulcanisates.
Effect of Chemical Modification of Poly(Butylene Terephthalate) on Elastic Properties
Authors: Ukielski R. , Lembicz F.
Published: September 2018

It can be stated, on the basis of the investigations presented in this article, that chemical modification of the PBT chain as a result of introducing cheap and readily available modifying comonomers – PTMOG and DMI – with a view to improving the elastic and impact properties, achieved the intended results. Improvement of these characteristics while at the same time maintaining very good thermal and strength properties is obtained in the case of polymers 3, 7 and 8, i.e. PBT modified with DMI alone at 6 wt.%, with a system 6 wt.% DMI + 6 wt.% PTMOG or with PTMOG alone at 20 wt.%.

These polymers are best at meeting the requirements of customers, especially manufacturers of domestic appliances.
Plate out – more than Just a Phenomenon? Part 2. Plate out in the Extruder
Authors: Gilbert M , Haberleitner R , Schiller M , Varshney N , Walon M
Published: September 2018

“Is this the real life? Is this just fantasy…” [1] - this is probably what readers will ask when the mechanisms for the formation of plate out are postulated. While the first part of this article summarised the literature on the subject, this second part reports on the extensive experimental work in this field. These investigations provide information on the processing window for waxes. They also demonstrate the correctness and validity of the mechanism described by Lippoldt for lead-stabilised systems as well.
Optimising the Properties of Oil-resistant Thermoplastic Elastomer Composites
Authors: Novokshonov V.V. , Musin I.N. , Kimel'blat V.I.
Published: September 2018

In blends of rubbers and plastics of similar nature, for example ethylene–propylene rubber and a polyethylene, delocalised interfaces can be formed at which molecular dispersed mixing of macromolecules of different nature is observed.
Theory of the Adhesion of Solutions of High-molecular-weight Compounds and its Practical Application
Authors: Dolomatov M.Yu. , Timofeeva M.Yu.
Published: September 2018

A semi-empirical physicochemical theory of adhesion is proposed, describing adhesion in a wide range of concentrations in non-ideal media with strong intermolecular interaction.
Effect of Organobentonites on the Properties of Aliphatic Polyamide PA-6
Authors: Pankrashkin A.V. , Sokolova Yu.V. , Pokid'ko B.V. , Tutorskii I.A. , Aizinson I.L. , Kalugina E.V.
Published: September 2018

Data are given on the effect of modified bentonites on the combination of physicomechanical and thermophysical properties of aliphatic PA-6. The results of tests of bentonites from different fields located on the territory of the former Soviet Union and treated with different modifiers in aliphatic PA-6 are given. Also, the effects of organobentonites and finely dispersed talc on the properties of PA-6 are compared.
The Formation of Boundary Layers in Glass-fibre-reinforced Plastics Based on Epoxy Resins
Authors: Trofimov A.N. , Kopytin V.S. , Komarov V.M. , Simakova G.A. , Simonov-Emel'yanov I.D.
Published: September 2018

A study has been made of the adsorption of epoxy oligomer ED-20 on the surface of glass. Comparison of experimental results with adsorption layer characteristics calculated on the basis of a theoretical model indicates that adsorption in the investigated system is polymolecular.
Modelling of Solid-phase Polymerisation
Authors: Kaplan A.M. , Chekunaev N.I.
Published: September 2018

A model of solid-phase polymerisation is developed, based on the catalysing role in this process of carriers of excess free volume – mobile structural defects. Using the given model, it proved possible for the first time to explain most non-trivial kinetic features of radiation-initiated solid-phase polymerisation.
Calculation of the Geometry of Articles Produced by Free Thermoforming through Elliptical Apertures
Authors: Gusev K.V. , Sheryshev A.E. , Sheryshev M.A.
Published: September 2018

The determination of the geometry of articles produced by free thermoforming through elliptical apertures is examined. The surface of the article is determined using Coons’ method.
Study of the Curing of Basalt-fibre-reinforced Plastic Based on a Phenol–formaldehyde Binder
Authors: Simonov-Emel'yanov I.D. , Miichenko I.P. , Shembel N.L. , Kuklin A.S. , Trofimov A.N.
Published: September 2018

A study was made of the kinetics of curing of phenol–formaldehyde binders (PFBs) in microplastics based on basalt fibre by mechanical spectrometry and in basalt-fibre-reinforced plastics based on chopped fibre by rotation viscometry. The possibility was shown of increasing the pultrusion rate of rods by reducing the degree of curing of the PFB to 0.5–0.6 in the forming channel with subsequent heat treatment to increase the strength of basalt-fibre-reinforced plastic rods.
Hydrolysis of Polyacrylonitrile and Copolymers of Acrylonitrile
Authors: Alekseev A.A. , Ordina E.V. , Osipchik V.S.
Published: September 2018

The hydrolysis of powder polyacrylonitrile and copolymers of acrylonitrile in order to produce water-soluble polymers is investigated.
Investigation of the Possibility of Using Filled Polyurethane Materials as Protective Coatings
Authors: Volkova E.R. , Tereshatov V.V.
Published: September 2018

An investigation was made of polyurethanes for application as anticorrosion materials in different sectors of the national economy.
Biodegradable Polymers Based on Polypropylene and Composite Additives
Authors: Gogotov I.N. , Gerasin V.A. , Barazov S.Kh. , Ponomarev A.N.
Published: September 2018

It is shown that, on exposure to UV radiation, or solar radiation, the degradation of composite polypropylene occurs, the rate of which depends on the nature of the biodegrading additives that it contains, the exposure time, and the thickness of the specimens.
Investigation of Cotton Cellulose and its Products using Customs Chemical Appraisal
Authors: Karimkulov K.M. , Askarov M.A.
Published: September 2018

The chemical properties of cotton cellulose were studied. Analytical procedures are given for lignin, α-cellulose, etc.
Polyurethane for Special Sealing Applications and a Comparison to Rubber
Authors: Hieber J.
Published: September 2018

Polyurethane materials have been known for decades. More recently thermoplastic polyurethanes (TPUs) have been introduced. These materials represent an alternative to either conventional thermoplastics or rubber, depending on the hardness. TPUs have a substantially higher tear propagation resistance and abrasion resistance than rubber, but for a long time they remained very vulnerable to hydrolysis and had poor compression set. Recent developments by raw material manufacturers have significantly improved the hydrolysis resistance. However, as sealing applications also require very good compression set values, the greatest improvements in this area have been achieved by the major seal manufacturers who synthesise their own polyurethane. TPUs are clearly the sealing material of choice for applications in hydraulics systems and are increasingly taking over from rubber. Recent developments have succeeded in obtaining excellent low-temperature flexibility combined with good compression set at high temperatures. For special sealing applications in the food sector, however, good hydrolysis resistance is no longer sufficient in itself. A new range of materials developed for this sector offers resistance to CIP/SIP media that is even better than that of many conventional elastomers.
Effect of Plasticisation and the Degree of Biaxial Orientation on the Electrical Properties of Polyvinyl Chloride
Authors: Fatoev I.I. , Mavlanov B.A. , Murodova I.N.
Published: September 2018

An investigation was made of plasticised PVC. The electrical properties of the investigated PVC specimens proved to be sensitive both to the degree of biaxial orientation and to the content and nature of plasticisers in the system.
Influence of the Construction of the Porous Structure of Polyvinyl Chloride on the Removal of Residual Vinyl Chloride
Authors: Gutkovich S.A.
Published: September 2018

Average values of the packing density of particles of suspension PVC were calculated using a theoretical model of overlapping spheres.
Packaging Materials Manufactured from Natural Polymers Modified with Silver Nanoparticles
Authors: Fedotova A.V. , Snezhko A.G. , Sdobnikova O.A. , Samoilova L.G. , Smurova T.A. , Revina A.A. , Khailova E.B.
Published: September 2018

The effect of silver nanparticles on the bactericidal and fungicidal properties of natural polymers – cellulose and collagen derivatives – was investigated. It was found that the treatment of films in a silver solution leads to a change in structure: ordering and compaction of microfibres. It is shown that the new materials, having fairly high bactericidal properties to different types of microorganism, are non-toxic and risk-free to humans and the environment.
Comparison of Various CSR Methods regarding the Static Long-term Sealing Behaviour of AEM, ACM and HNBR Compounds
Authors: Hornig R.
Published: September 2018

The purpose of this study is to provide a guide to the various methods for compression stress relaxation testing (CSR testing), to assessing the influences of various parameters on the measurement results and to understanding different evaluation variants. It also presents a measuring method developed by ElringKlinger AG together with its various evaluation options. As the experiments in this study show, CSR compression methods developed by Shawbury-Wallace, Wykeham-Farrance and Jamak, which often produce very different static long-term sealing force curves, can be replicated sufficiently accurately by the EK method if the right evaluation variant is chosen. In addition, identical compression stress conditions must be established in the specimen by means of its geometrical design. The CSR methods are surprisingly simple to use and versatile in terms of the choice of test parameters and conditions. The various CSR measuring methods are used to plot the static long-term sealing force curves for AEM, ACM and HNBR compounds in hot air and in SF105G engine test oil. The influences of materials and sealing profiles in CSR testing are also discussed.
Nanocomposite Materials Based on High-density Polyethylene with Increased Thermomechanical and Physicomechanical Properties
Authors: Turaev E.R. , Khashirova S.Yu. , Bedanokov A.Yu. , Dzhangurazov B.Zh. , Mikitaev A.K.
Published: September 2018

A study was made of the influence of the quantity and nature of organomodifiers on the thermomechanical and physicomechanical properties of nanocomposites based on high-density polyethylene. The formation of crystalline structures when organoclay was introduced is shown. New nanocomposites are proposed that can be used in structural articles on account of their high mechanical properties.
The Synthesis and Properties of Oligohydride (organo) Siloxanes with Pharmacophoric 3,5-dichloropyridyl-containing Ligands
Authors: Izmailov B.A. , Vasnev V.A. , Rodlovskaya E.N. , Markova G.D. , Yambulatova O.V. , Uvarov B.A.
Published: September 2018

A method has been developed for the chemical assembly of molecular structures based on 3,5-dichloropyridine derivatives and oligohydride (organo)siloxanes on the surface of textile cellulose materials. The modified textile materials possess effective fungicidal activity and good hydrophobic properties.
The Synthesis of Phenol–formaldehyde Copolymers Based on Phthalide-containing Monophenol
Authors: Machulenko L.N. , Nechaev A.I. , Salazkin S.N. , Komarova L.I. , Petrovskii P.V.
Published: September 2018

Phthalide-containing monophenol 3-phenyl-3-(41-hydroxyphenyl)phthalide (I) was synthesised by the interaction of o-benzoylbenzoic acid chloride with phenol in a dioxane solution in the presence of catalyst ZnCl2. Resol-type phenol-formaldehyde cooligomers and heat-resistant polymers based on them were obtained by the interaction of a mixture of the synthesised monophenol and phenol in different weight ratios (from 5:95 to 40:60).
New Transparent Cyclopropane-containing Polymers
Authors: Guliev K.G.
Published: September 2018

A new transparent polymer based on substituted polystyrenes was investigated.
The Interaction of Polyesters and Polymethylene Esters of Phenols and Boric Acid with Epoxy Resin
Authors: Androshchuk A.A. , Lenskii M.A. , Belousov A.M.
Published: September 2018

An investigation was made of the interaction of new heat-resistant boron-containing polymers (polyesters of phenols and boric acid) with epoxy resin. A mechanism of this interaction is proposed, consisting in the formation of bonds between carbon of the epoxy group and carbon located in the o-position of phenyl radicals of the polymers.
The Supermolecular Structure of New Copolymer Products Based on Cyclic Carbonates
Authors: Beilin I.L. , Arkhireev V.P.
Published: September 2018

The copolymerisation of cyclic carbonates with monoisocyanates under conditions of anionic initiation has been carried out for the first time. On the basis of the conducted X-ray diffraction analysis it was established that the substances synthesised possess a high degree of crystallinity with a fairly large and complex elementary cell of low syngony (symmetry of crystals).
Development of the Compositions of Concentrates and Methods of Obtaining them for the Production of Crosslinked Polyolefin Composites
Authors: Chuleeva E.V. , Zolotarev V.M. , Pakharenko V.A.
Published: September 2018

The results of theoretical and experimental investigations into the development of compositions and methods of obtaining superconcentrates of crosslinking systems on porous polymer supports, and also a concentrate of light stabiliser, antioxidant, and process additive, are presented. The concentrates are intended for the effective crosslinking of polyolefin composites.
The Polymerisation of Methyl Methacrylate in the Presence of Gel-Effect Regulators
Authors: Volosova Yu.V. , Efimov A.L. , Gorelov Yu.P.
Published: September 2018

Data are given on the comparative effectiveness of methyl methacrylate bulk polymerisation regulators from the class of mercaptans (lauryl mercaptan) and terpene cyclic compounds with non-conjugated double bonds (γ-terpinene, terpinolene).
The Rheology of Rubber Compounds with Rubber Flour
Authors: Djagarova E.
Published: September 2018

During the course of investigations into the rheological characteristics of SBR rubber compounds containing rubber flour as a function of the rubber flour content, we observed some distinctive features. Based on the results for the activation energy of viscous flow of the compounds under investigation and the specific characteristics of the rubber flour particles, we put forward a hypothesis for the flow mechanism. The assumption can be made that the rubber flour particles are deformed in the viscous medium of the SBR matrix during flow. The degree of deformation is largely dependent on the presence of other ingredients in the compound (carbon black, stearic acid, carbon black + stearic acid). We suggest that the amount of unvulcanised rubber in the rubber flour particles is very important to the flow mechanism. It is also likely that rubber flour particles are broken up during flow. The proposed hypothesis for the flow mechanism is compared with the known models of “drop breakup in extensional flow”, “core-shell”, polymer blends comprising two incompatible polymers or comprising a thermoplastic and microgel particles, etc.
DuPont Kevlar Fibre. Part 3. Hybrid Cords, Short Fibres, and their Application in Composites with Thermoplastics and Thermosetting Plastics
Authors: Ioffe A.
Published: September 2018

Short or staple aramide fibres of the Kevlar type were tested as reinforcing agents for thermoplastic and thermosetting polymers.
Structural Transformations during the Low-Temperature Annealing of Biaxially Oriented Polypropylene Film
Authors: Bystritskaya E.V. , Karpukhin O.N. , Kutsenova A.V. , Lazareva O.L. , Popova E.I. , Sokovishin A.V.
Published: September 2018

By differential scanning calorimetry, and from the buildup of longitudinal shrinkage, a study was made of the kinetics of structural relaxation during the low-temperature annealing of biaxially oriented polypropylene film. It was established that the first, rapid stage of structural relaxation normally occurs in the process of product manufacture. The second, slow stage, comprising the process of secondary crystallisation, occurs in the course of storage and service. The kinetic parameters of secondary crystallisation and accompanying longitudinal shrinkage that make it possible to predict the kinetics of these processes in a wide range of temperatures and observation times were determined.
Optimising the Regime for the High-Frequency Welding of Plastics with Respect to the Depth of the Heat-Affected Zone
Authors: Markov A.V. , Trofimov N.V. , Yulenets Yu.P.
Published: September 2018

On the basis of an analysis of the temperature field in a thermoplastic placed in the corresponding processing equipment, an examination is made of the problem of determining the optimum regime parameters for the high-frequency welding of plastics. It is shown that the optimum process parameters are those ensuring a comparatively narrow depth of the heat-affected zone. The optimum depth of the heat-affected zone is determined for cases of the high-frequency welding of specimens of polyamide and polyvinyl chloride.
Study of the Kinetics of Swelling of Crosslinked Elastomers by Fourier Spectroscopy
Authors: Volkova E.R. , Astaf'eva S.A.
Published: September 2018

The existence of a non-stationary boundary regime arising during the swelling of polymer networks and responsible for abnormal diffusion kinetics of solvent absorption was established experimentally by IR Fourier spectroscopy.
Structural Parameter for Assessing the Control of the Properties of Carbon-Black-Filled Polymers
Authors: Bortnikov A.Yu. , Minakova N.N. , Abramenko E.A.
Published: September 2018

It was shown that, using fractal estimates of the texture of the microscopic image, it is possible to analyse the stability of the electrical conductivity of filled polymeric materials under service effects, and to identify stable structures by different methods of electrophysical property control.
Features of the Forming of the Viscoelastic and Strength Properties of Reinforced Epoxy Heterocomposites for High-Pressure Gas Cylinders
Authors: Norkulov A.A. , Khalimov Sh.A.
Published: September 2018

It is shown that increase in the proportion of discrete carbon fibres within the filler leads, along with increase in the logarithmic decrement of vibrations, to an increase in the dynamic modulus of unidirectional hybrid composites.
Biodegradable Polymer Composites Based on Agro-Industrial Complex Waste
Authors: Kirsh I.A. , Chutkina E.P.
Published: September 2018

This manuscript looks at questions to do with the creation of filled biodegradable polymer composites based on agro-industrial complex (AIC) and packaging waste with a view to producing raw material and items made from it. Attention is given to study of the physical/mechanical properties of filled biodegradable polymer composites. Processes of biodegradation of polymer composites filled with AIC wastes are considered.
Effect of Mineral Fillers on the Properties of Chemically Crosslinked Polyethylene Foam
Authors: Pankratov A.V. , Matyukhina G.N. , Panov Yu.T. , Fridman O.A.
Published: September 2018

An investigation has been made of the effect of whiting on the mechanical properties of chemically crosslinked polyethylene foam. The presence of up to 15% filler has little effect on the appearance of the foam. The apparent density of the foam increases little. The characteristics of the foam under compression are improved, and its tensile strength is increased.
Thermo-Oxidative Ageing of Peroxide-Crosslinked PEX-a Polyethylene at Elevated Temperatures and with Long-Term Storage
Authors: Gorbunova T.L. , Ioffe A.A. , Evseeva K.A. , Kalugina E.V.
Published: September 2018

This article gives the results of accelerated thermal ageing of PEX-a tube specimens in the 110-190°C temperature range. The results were mathematically processed using the traditional GOST standard attested method
Investigating the Crystallisation of Polyethylene Terephthalate Flakes and Hollow Fibre Extruded from them
Authors: Semenov D.S. , Kalugina E.V. , Ushakova O.B.
Published: September 2018

This article investigates the link between the properties of PET flakes and the quality of hollow fibre extruded from them. Demonstrates that to increase the void fraction in the fibre, the degree of stretching of the fibre melt during moulding needs to be increased; this will make the walls of the moulded fibre thinner and will consequently cause a rise in the void fraction in the fibre.
Nanocomposite films with UV-Protective Properties Based on Polyethylene with Ultra-Disperse Silicon
Authors: Ol'khov A.A. , Gol'dshtrakh M.A. , Krutikova A.A. , Ishchenko A.A. , Liao D. Dzh. , Fetisov G.V. , Kononov N.N. , Storozhenko P.A.
Published: September 2018

Polymer film materials based on polyethylene containing between 0.5% and 1.0% by wt. nanocrystalline silicon (ncSi) with excellent strength properties have been produced. Specimens of ncSi with a mean core diameter of 7–10 nm were synthesised using plasma chemistry methods and laser-induced breakdown of monosilane. Spectral studies indicate an almost total (up to ~95%) absorption of UV radiation by films 85 microns thick in the 200–400 nm area with a 1.0% by wt. ncSi content in them. Using the method of full-profile modelling of X-ray diffraction patterns, and assuming that the crystallites are spherical in shape and have a log-normal distribution, the particle size distribution density functions in the initial powders and polymer films containing immobilised silicon nano-crystallites were derived. X-ray analysis results show that the distribution function for crystallite dimensions remains virtually unaltered with implantation of initial ncSi specimens in a polymer matrix, while the degree of crystallinity of the initial polymer increases (~10%).
New Thermo-Oxidative Degradation Inhibitors for Polyolefins
Authors: Murzakanova M.M. , Zalova T.V. , Borukaev T.A. , Mikitaev A.K.
Published: September 2018

The possibility of inhibiting the thermo-oxidative degradation of polyolefins with low-molecular-weight melamine-based azomethines is considered. The dependence of the stabilising properties of low-molecular-weight azomethines on their chemical structure is shown, and the effectiveness of these properties is demonstrated.
Adhesion Properties of a Paper (Carboard)–Polyethylene Combined Material Obtained by the Extrusion Laminator Method. Part 2
Authors: Anan'ev V.V. , Chalykh A.E. , Bannikova O.A.
Published: September 2018

An investigation has been made of the wetting of the surface of paper by polyethylene for determining the adhesion interaction during extrusion lamination, especially in high-speed processes.
Chemical Resistance of Three-Dimensional Polymers of Oligoester Acrylates
Authors: Sivergin Yu.M. , Kireeva S.M.
Published: September 2018

An investigation was made of the chemical resistance of three-dimensional polymers of oligoester acrylates in organic solvents. The solubility parameter and the polygon of swellability of the polymers were found.
Development and Investigation of Solid Polymer Electrolytes
Authors: Smirnov S.S. , Lovkov S.S. , Putsylov I.A. , Smirnov K.S. , Savost'yanov A.N.
Published: September 2018

A solid polymer electrolyte based on fluorine-containing polysulphone has been developed that is superior in electrical conductivity to existing analogues. The electrolyte possesses high stability and inertness in relation to the electrodes of lithium sources of electric current and ensures reversibility of the charge–discharge process of metallic lithium.
The Relationship between the Structural Transformations and Properties of Polyolefin Articles Produced by Solid-Phase Forming
Authors: Budnitskii Yu.M.
Published: September 2018

Processes of solid-phase forming of polyolefins – polyethylene, polypropylene, ultrahigh-molecular-weight polyethylene – by die stamping and profile moulding were investigated, and the influence of process conditions on the morphological features and properties of the articles was shown.
Assessing the Effectiveness of Modifying High-Density Polyethylene with Thermoplastic Elastomers and Organobentonites
Authors: Chalaya N.M. , Kazanchyan A.E. , Osipchik V.S. , Krasnov K.V. , Averin R.M.
Published: September 2018

The results of modifying high-density polyethylene (HDPE) by introducing thermoplastic elastomers (TPEs) and organobentonite (OB) are presented. An investigation has been made of the influence of the amount and the methods of introduction of a styrene–ethylene–butylene–styrene thermoplastic elastomer, including a maleinised thermoplastic elastomer (SEBS-M), and OB on the physicomechanical properties of the polymeric material obtained. The effect of modifiers on the impact strength of specimens, determined by the free-falling-weight method, is analysed in detail. It is shown that this method is the most informative for determining the effectiveness of modifying HDPE with thermoplastic elastomers and organobentonite.
Influence of Moisture Sorption on the Physical and Mechanical Properties of Plasticised Poly(Ether Urethane Ureas)
Authors: Tereshatov V.V. , Strel'nikov V.N. , Makarova M.A. , Senichev V.Yu. , Volkova E.R.
Published: September 2018

This paper looks at patterns in the mechanical behaviour of plasticised poly(ether urethane ureas) over a wide range of relative air humidity values. In the presence of a plasticiser that lowers the solubility of rigid blocks in the flexible phase of the polymer, the stability of the mechanical characteristics of poly(ether urethane urea) with exposure to a humid atmosphere is shown to increase.
Biodegradation of Polyethylene Composites Based on Starch and Ultra-Disperse Metal Particles
Authors: Beslaneeva Z.L. , Sherieva M.L. , Mashukov N.I. , Shustov G.B.
Published: September 2018

This paper presents a modification of biodegradable polymers with highly-disperse metals, for example Fe/FeO or Fe2O3 (Z), with nano-sized particles. During the course of the work, biodegradable polyethylene composites with the composition PE-276 + Z + starch (Z = 0.1% by wt, starch from 2.5 to 10% by wt) were produced. Studies were made of the rheological and deformation/strength characteristics of the composites produced. A regular relationship was identified between the rate and extent of biodegradation and the percentage starch content in the composites.
Gendered il/legalities of housing formalisation in India and South Africa
Authors: Meth Paula , Buthelezi Sibongile , Rajasekhar Santhi
Published: September 2018

Urban interventions, such as state-led housing provision in India and South Africa, establish new legal landscapes for urban residents (formerly slum/informal dwellers), who become home owners, legal occupiers of spaces, ratespayers and visible citizens although not in ways that are necessarily contingent. These material-legal processes are also acutely gendered underscoring wider calls for a feminist approach to legal geographies. Informed by a comparative empirically driven study, this paper explores how in both contexts, urban interventions work to enhance gender equality through improving women’s material shelter in the city, and introduce tenure security, often prioritising very poor women. Yet, their implementation is riddled with slippages as well as operating within a broader poverty–patriarchy nexus. This means that these legally framed benefits have occurred alongside complex and perverse outcomes including unemployment, gendered tensions and acute loss of privacy for some. Housing interventions produce uneven legal geographies, with persisting gendered inequalities and poverty distorting residents’ abilities to benefit from material-legal interventions aimed at improving their lives.
Forming and springback prediction in press brake air bending combining finite element analysis and neural networks
Authors: Miranda Sara S , Barbosa Manuel R , Santos Abel D , Pacheco J Bessa , Amaral Rui L
Published: September 2018

Press brake air bending, a process of obtaining products by sheet metal forming, can be considered at first sight a simple geometric problem. However the accuracy of the obtained geometries involves the combination of multiple parameters directly associated with the tools and the processing parameters, as well as with the sheet metal materials and dimensions. The main topic herein presented deals with the capability of predicting the punch displacement process parameter that enables the product to be accurately shaped to a desired bending angle, in press brake air bending. In our approach, it is considered separately the forming process and the elastic recovery (i.e. the springback effect). Current solutions in press brake numerical control (computer numerical control) are normally configured by analytical models developed from geometrical analysis and including correcting factors. In our approach, it is proposed to combine the use of a learning tool, artificial neural networks, with a simulation and data generation tool (finite element analysis). This combination enables modeling the complex nonlinear behavior of the forming process and springback effect, including the validation of results obtained. A developed model taking into account different process parameters and tool geometries allow extending the range of applications with practical interest in industry. The final solution is compatible with its incorporation in a computer numerical control press brake controller. It was concluded that, using this methodology, it is possible to predict efficient and accurate final geometries after bending, being also a step forward to a “first time right” solution. In addition, the developed models, methodologies and obtained results were validated by comparison with experimental tests.
Using Indicators to Assess Sustainable Transportation and Related Concepts
Authors: Ramani Tara
Published: September 2018

The overall goal of this study is to assess the concept of sustainability in relation to the related concepts of “health” and “livability” that have emerged in transportation planning discourse. This study achieves the goal using an indicator-based case study, conducted for the El Paso metropolitan area in the United States. Data from the regional travel demand model and other sources were used to quantify a sustainability index, livability index, and health index for individual traffic analysis zones in the region, for four analysis years over a 30-year planning horizon. Each index was comprised of representative indicators, which were normalized and aggregated in accordance with common multi-criteria decision-making methods. The analysis results demonstrated little correlation between the quantified livability, sustainability, and health indices developed for the El Paso region. The indices also showed relatively low levels of change over time for a location. That is, the relative performance of a traffic analysis zone tended to stay the same, despite the modeled changes to the transportation system, demographics, and land use. The main implication of the research findings is that despite overlaps at a theoretical level, concepts such as livability and health cannot necessarily serve as proxies for sustainability when implemented in practice. The study also provides insight into the challenges of making meaningful change in the area of sustainability over time and highlights the influence of factors beyond transportation, such as land use and socio-economic issues.
Traffic Shockwave Detection in a Connected Environment using the Speed Distribution of Individual Vehicles
Authors: Elfar Amr , Xavier Connie , Talebpour Alireza , Mahmassani Hani S.
Published: September 2018

Traffic shockwaves reflect a transition from the free-flow traffic state to the congested state. They create potentially unsafe situations for drivers, increase travel time, and significantly reduce freeway capacity. Several shockwave detection methods based on loop detector data and other traditional databases have been around for years. However, these methods face certain accuracy and reliability issues, many of which are due to the nature and accuracy of available data. Connected-vehicles technology is expected to provide reliable and accurate data about individual vehicles that can be potentially used for shockwave detection. Accordingly, this paper presents a novel method to identify shockwave formation and track its propagation based on the speed distribution of individual vehicles available through connected-vehicles technology. In addition, this paper analyzes the impact of partial connectivity on shockwave identification and compares the accuracy of the proposed method to a wavelet transformation-based method. Vehicle trajectories from the Next Generation Simulation (NGSIM) US-101 dataset were analyzed. The analysis shows a consistent pattern in which shockwave formation, indicated by a drop in speed propagating over space and time, is associated with a sharp increase in the value of speed standard deviation (SSD). Furthermore, the analysis shows that shockwaves can be accurately identified using vehicle trajectory data from connected vehicles at minimum 30% market penetration rates. Finally, the results show that the SSD of individual vehicles is more responsive to shockwave formation than the mean speed wavelet transformation, which can lead to improved shockwave detection accuracy.
Impact of Extreme Events on Transportation Infrastructure in Iowa: A Bayesian Network Approach
Authors: Kulkarni Abhijit R. , Shafei Behrouz
Published: September 2018

Iowa’s roadway network is an important part of the state’s transportation infrastructure and plays a critical role in the functionality and economic development of the entire state. This network primarily consists of three interstate highways that pass through Iowa, connecting it to the neighboring states and eventually Canada. Various businesses are located near this roadway network and rely on it for everyday operation. In recent years, however, the growth of agricultural and biofuel industries has intensified the demand on the roads and bridges in Iowa. The state’s roads and bridges have also witnessed a number of flooding events, which have caused extensive traffic disruptions and economic losses. Thus, it is imperative to develop a fundamental approach to evaluate the impact of extreme events on the transportation infrastructure of Iowa and other similar states. Towards this goal, the current study investigates the existing condition of Iowa’s transportation infrastructure, possibility of occurrence of extreme weather events, and scenarios that may lead to the failure of transportation infrastructure components. For this purpose, the capabilities of Bayesian belief networks are utilized to quantify the effects of extreme precipitation and extreme temperature on the performance of transportation infrastructure and then predict the probability of damage to roads and bridges. This will be achieved through the identification of the most influential factors using a set of sensitivity analyses, assessment of overall vulnerability with evidence-based propagation analyses, and quantification of response to extreme weather events, taking into consideration climate projections.
Political Economy of Embodiment: Capitalizing on Globally Staged Bodies in Nigerian Beauty Pageants and Vietnamese Sex Work
Authors: Balogun Oluwakemi M. , Hoang Kimberly Kay
Published: September 2018

How do various stakeholders capitalize off of display workers’ bodies? This article uses a comparative-case approach to examine two different sites—beauty pageants in Nigeria and high-end sex workers in Vietnam—where women’s bodies are differentially staged with varying degrees of visibility. Theoretically, this article develops the concept of political economy of embodiment to account for a network of people onstage, backstage, and offstage who capitalize off displayed bodies in qualitatively different ways. Beauty pageants in Nigeria take place on highly visible national and global stages. Contestants’ bodies signal African beauty as being fashion-forward, which propels and integrates Nigeria into international arenas of diplomacy and trade. High-end sex workers in Vietnam work on a stage that is hidden from the general public yet open for a select group of Vietnam’s elites. Sex workers’ bodies are on display to project an ideal of Asian ascendancy in Vietnam’s market.
Crashworthiness of cardboard panels reinforced with braided glass fiber rods for vehicle side impact protection
Authors: Fortin Gabriel Y , Elbadry Elsayed A , Hamada Hiroyuki
Published: September 2018

This paper investigates the quasi-static compression properties of cardboard panels reinforced with braided glass fiber rods manufactured using a tubular braiding method. Compression tests are performed on single- and two-layer panels reinforced with varying number of rods and panel layer orientation. The crushing results of single-layer panels show more progressive crushing behavior than those of two-layer panels for different number of rods. In two-layer panels, certain rods are inclined from the direction of applied load due to deformation of the surrounding cardboard, resulting in reduced specific energy absorption compared with single-layer panels. Moreover, panels consisting of two layers of cardboard oriented in the same direction perform better than when the layers are off-set 90° where cardboard shifting is more pronounced. The role of cardboard is to constrain the rods from excessive splaying, causing greater levels of fiber fragmentation which consumes more energy compared with rods without cardboard.