bluuebunny/crossref_metadata_2025 huggingface dataset:
The Impact of Mould Temperature and Blowing Agent Content on Structure and Properties of Injection Moulded Parts
Authors: Bociaga Elzbieta , Palutkiewicz Pawel
Published: September 2018

The investigation of the influence of mould temperature and blowing agent percentage on structure, and selected properties (weight, mechanical properties, surface state - gloss and colour) of moulded parts from HDPE was the aim of this work. The structure of moulded parts in cross-section perpendicular and parallel to the direction of polymer flow, and quantitative assessment of porous structure using microscopic image analysis were carried out. It was shown that the content of blowing agent in polymer influences not only the amount of pores in the part core, but also the thickness of solid skin. Lower mould temperature favors the formation of a fine porous structure. The formation of the porous structure influenced slightly the weight and mechanical properties of moulded parts. With the increase in blowing agent content, the gloss of parts decreased and also caused the change in their colour. Parts with higher amount of blowing agent were brighter.
Tailor-Made High Density PLA Foam Sheets - Strategies to Improve the Mechanical Properties
Authors: Geissler Bernd , Feuchter Michael , Laske Stephan , Walluch Matthias , Holzer Clemens , Langecker Günter R.
Published: September 2018

In this study, different strategies to improve the mechanical properties of physically foamed high density polylactic acid (PLA) sheets were examined to produce PLA foam sheets with tailor-made mechanical properties. The first part was the determination of the influence of the blending of PLA with polybutylene succinate (PBS) on the properties of the high density foam sheets. Additionally, the influence of the PBS on the rheological properties was investigated with a cone plate rheometer. The second part was to manufacture multilayer films with a physically foamed middle layer and highly filled skin layers. The foamed sheets were characterized in terms of mean cell size, cell density, density and surface roughness. The experiments were carried out on lab scale multi-layer extrusion line.
Preparation of Polyurethane Flexible Foam Nanocomposites by Incorporation of Fe3O4Nanoparticles Modified by Reaction Product of GPTS and APTS
Authors: Nikje Mir Mohammad Alavi , Kalishomi Razieh Ghavidel , Akbar Raheleh
Published: September 2018

Synthesis and characterization of magnetic flexible polyurethane foam (PUF) nanocomposites is reported. In order to improving dispersion and preventing aggregation of Fe3O4nanoparticles in the polymer matrix, this material was modified by synthesized dipodal silane (ECA), the reaction product of 3-aminopropyltriethoxysilane (APTS) and γ-glycidoxypropyltrimethoxysilane (GPTS). The chemical structure of synthesized ECA was identified by nuclear magnetic resonance spectroscopy (1HNMR) and Fourier transform infrared spectroscopy (FT-IR), respectively. Magnetic flexible polyurethane foam nanocomposites prepared by the incorporation of ECA-modified Fe3O4nanoparticles and characterized by their apparent density, thermogravimetric analysis (TGA), magnetic properties analysis (VSM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and FT-IR spectra, respectively. The TEM and SEM images indicated that the nanoparticles were dispersed homogeneously in PUF matrix. Finally, it was confirmed that the thermal and magnetic properties of magnetic PUF nanocomposite depend on the amount of magnetic nanoparticles.
Physical Properties of Bio-Based Polyurethane Foams from Bio-Based Succinate Polyols
Authors: Sonjui Tatcha , Jiratumnukul Nantana
Published: September 2018

The goal of this work is to study the physical properties of bio-based polyurethane (PU) foams prepared from synthesized bio-based succinate polyols. Bio-based succinate polyols were synthesized by condensation reaction using succinic acid (SA) and four types of glycols that are diethylene glycol (DEG), triethylene glycol (TEG), tetraethylene glycol (TTEG) and glycerol (Gly). The effects of glycol types (single or mixed glycols) used in the prepared polyols toward physical properties of PU foams were studied. Physical and mechanical properties of the prepared PU foams were taken relatively to PU foam obtained from a commercial polyol. The results revealed that hydroxyl number (OH number) and viscosity of prepared polyols decreased as the length of the glycol chains increased (DEG < TEG < TTEG). However, the polyols prepared from mixed glycols showed higher viscosity than those prepared from single glycol. Optical micrographs images showed that the PU foams prepared from mixed-glycol polyols had smaller cell dimension and more closed cell contents compared to ones prepared from single-glycol polyols. Foam formation time and density of foams prepared from DEG-glycerol mixed glycol polyol were similar to one prepared from commercial polyol (POLIMAXX A8360). Moreover, compressive strength of foam was higher than one prepared from commercial polyol.
Modeling of Radiative Properties of Polystyrene Foams Containing IR-Opacifiers
Authors: Arduini M. , Manara J. , Vo C.
Published: September 2018

The addition of opacifiers in foams considerably reduces the radiative thermal conductivity and consequently enhances the insulation performance of the foams. In this work two different methods were developed to calculate the spectral specific extinction coefficient of opacified extruded polystyrene (XPS) foam material. Cell morphology and thermal conductivity of two identical XPS-foams, one opacified with 3 wt% carbon black as opacifier and one without opacifier, were thoroughly characterized. The experimental results were in a good agreement with the theoretical results obtained from two different computing techniques. These methods allow a good prediction of the specific extinction coefficient of arbitrary opacified foam material.
Brief Communication
Authors: Ma Dewang , Wang Dazhi , Zhang Shaoyin , Cai Weijie
Published: September 2018

A novel poly (arylene ether sulfone) with sodium carboxylate groups was designed and synthesized through direct polycondensation. The as-prepared polymer possessed a cellular structure with an average pore size less than 10 μm and a tap density of 1.333 g/cm3. The cellular polymer exhibited lightweight property and excellent adsorption capacity for heavy metal ions in simulated wastewater. This might shed light on the development of cellular polymeric materials for heavy metal pollutant treatment.
Preparation and Properties of Styrene Butadiene Styrene/Nano Calcium Carbonate Thermoplastics Elastomer Composite Foams: Morphology and Mechanical Properties
Authors: Vahidi Maryam , Azizi Hamed
Published: September 2018

In this study, nanocomposite foams based on styrene-butadiene-styrene (SBS) copolymer and nanosized calcium carbonate (CaCO3) were prepared using chemical blowing agent (modified Azodicarbonamide) by compression molding at (230°C) temperature and (30MPa) pressure. The effect of nano CaCO3 concentration on cell nucleation rate, foam density, morphology and mechanical properties were studied for all samples. It was found that foam morphology and strength affected by nanofiller addition and its concentration. The results showed that SBS nanocomposite foam with 5 phr of CaCO3 nanoparticles have more cell density and smaller size cells compared with another samples. mechanical properties in compressive mode for foams were improved by increasing nano calcium carbonate content.
Applications of Core Retraction in Manufacturing Low-Density Polypropylene Foams with Microcellular Injection Molding
Authors: Kharbas Hrishikesh , Ellingham Thomas , Turng Lih-Sheng
Published: September 2018

Without modifying existing part and mold designs, the conventional microcellular injection molding (MIM) process can typically save about 5–10% material without encountering problems such as incomplete filling, excessive shrinkage, or deteriorating microstructure and mechanical properties. In this study core retraction was used in combination with the MIM process to produce thick polypropylene (PP) parts (up to 7.6 mm thick) with high density reductions of 30% and 55%. The cavity volume was modified by changing the retraction distance, which enabled control of density reductions. The lowest densities were achieved with this core retraction-aided microcellular injection molding (CR-MIM) process, the results of which could not have been achieved by the conventional MIM process alone. The effects of delay time in core retraction and weight reduction on the microstructure of the core and skin layers were investigated. It was shown that the CR-MIM process yielded better microstructure and tensile properties than the conventional MIM process. Use of core retraction also yielded more consistent densities and tensile properties throughout the length of the foamed parts.
Effect of Recycling on the Cellular Structure of Polylactide in a Batch Process
Authors: Ludwiczak Joanna , Frąckowiak Stanisław , Łużny Rafał
Published: September 2018

The aim of the work is to demonstrate the possibility of using recycled biodegradable material as a cellular material with a reduced weight. An experimental study on the influence of recycling on the properties and foam ability of polylactide (PLA) was carried out. The influence of recycling on the polymer crystallinity, thermal and viscoelastic properties was investigated. During the batch process the cellular structure in PLA and recycled PLA were created. A higher degree of crystallinity, a lower viscosity value and a lower melt strength for recycled PLA, as compared to original material, were observed. For the recycled PLA, a fine cellular structure and low density (0.60 g/cm3) were obtained.
Cellular Morphology Optimization of Polypropylene/CaCO3 Composite Films Designed for Piezoelectric Applications
Authors: Audet Eric , Mighri Frej , Rodrigue Denis , Ajji Abdellah
Published: September 2018

In this work, the cellular morphology of polypropylene (PP)/calcium carbonate (CaCO3) composite films was optimized with respect to piezoelectric cellular films criteria. To do this, a series of PP films filled with CaCO3 micro-particles of three different particle sizes (3, 6 and 12 microns) were developed at various weight concentrations (3 to 44 wt. %). Before going through a gas diffusion expansion (GDE) step to inflate the initiated cells, all composite films were first produced via extrusion/calendaring then biaxially stretched to initiate the cellular structure by interfacial delamination between the CaCO3 particles and PP matrix. After biaxial stretching and GDE, it was observed that only films with filler contents above 23 wt.% and 12 μm particle size presented a well-developed cellular structure. By optimizing the extrusion, biaxial stretching and GDE steps, we were able to generate a required cellular morphology where the average cell height ranged between 5 and 8 μm, which is considered good for further Corona charging. Also, the average cell aspect ratio (cell length divided by cell height) ranged between 4 and 10 with an average cell wall thickness between 7 and 12 μm, which is also considered as optimum for good piezoelectric properties.
A qualitative exploration of patient and healthcare professionals’ views and experiences of palliative rehabilitation during advanced lung cancer treatment
Authors: Payne Cathy , McIlfatrick Sonja , Larkin Philip , Dunwoody Lynn , Gracey Jackie
Published: September 2018

Background:

Limited evidence exists on the impact of palliative rehabilitation during systemic treatment of advanced cancer.

Aim:

To explore the experiences and perceptions of patients and healthcare professionals on the feasibility and acceptability of palliative rehabilitation during advanced lung cancer treatment.

Design:

Qualitative design using individual semi-structured interviews transcribed verbatim and analysed thematically.

Setting/participants:

Eight patients and six healthcare professionals were recruited from a regional cancer centre in the United Kingdom following completion of a 6-week individualised behaviour change study which combined physical activity and nutritional guidance.

Results:

Palliative rehabilitation and study participation were positively viewed by both participants and healthcare professionals. Five themes were identified from patient interviews within an overarching theme of living with and beyond an advanced cancer diagnosis: (1) challenges of living with incurable cancer, (2) personal and altruistic reasons for participating in rehabilitation, (3) applicability of palliative rehabilitation content, (4) barriers and facilitators to adherence and (5) positive impact on self and others. Three themes were identified from healthcare professionals, within an overarching theme of palliative rehabilitation: exploring the concept (1) pre-study-mixed perceptions of palliative rehabilitation, (2) perceived benefits for patients and families and (3) lessons for future research.

Conclusion:

Patients described personal benefits associated with setting their own goals for physical activity and dietary intake. Healthcare professionals who initially expressed a negative or indifferent stance towards palliative rehabilitation, displayed a mind-set change and were keen to explore further opportunities to expand the evidence base.
Does getting high hurt? Characterization of cases of LSD and psilocybin-containing mushroom exposures to national poison centers between 2000 and 2016
Authors: Leonard James B , Anderson Bruce , Klein-Schwartz Wendy
Published: September 2018

Background:

Lysergic acid diethylamide (LSD) and psilocybin are serotonergic hallucinogens that are used primarily for recreational abuse. Small studies evaluated the efficacy of LSD and psilocybin for several psychiatric conditions. There are limited safety or toxicity data for either of these substances, especially in large populations.

Methods:

This was a retrospective analysis of single-substance exposures of LSD or psilocybin-containing mushrooms (PcMs) reported to United States poison centers from 1 January 2000 to 31 December 2016. The study describes the most frequent toxicities, management sites, and medical outcomes.

Results:

A total of 5883 PcM and 3554 LSD exposures were included. Most patients were between 13 and 29 years of age (83.9% PcM, 88.9% LSD) and primarily male (77.9% PcM, 74.1% LSD). Most common clinical effects were hallucinations (45.8% PcM, 37.4% LSD), agitation (24.1% PcM, 42.4% LSD), and tachycardia (18.0% PcM, 38.6% LSD). Serious clinical effects were infrequent, but included hyperthermia, seizures, coma, increased serum creatinine, and cardiac arrest. Most patients were treated and released from the emergency department. More LSD patients were admitted to critical care and non-critical care units than PcM patients. Moderate effect was the most frequent outcome for both substances (61.0% PcM, 62.3% LSD).

Conclusion:

These data find that LSD and PcM use occurs primarily in adolescents and young adults, who experience mild to moderate adverse effects. Serious effects are infrequent but can occur. While most LSD and PcM users require only emergency department management, LSD use is more likely to require medical admission.
Reduced acquisition time PET pharmacokinetic modelling using simultaneous ASL–MRI: proof of concept
Authors: Scott Catherine J , Jiao Jieqing , Melbourne Andrew , Burgos Ninon , Cash David M , De Vita Enrico , Markiewicz Pawel J , O'Connor Antoinette , Thomas David L , Weston Philip SJ , Schott Jonathan M , Hutton Brian F , Ourselin Sébastien
Published: September 2018

Pharmacokinetic modelling on dynamic positron emission tomography (PET) data is a quantitative technique. However, the long acquisition time is prohibitive for routine clinical use. Instead, the semi-quantitative standardised uptake value ratio (SUVR) from a shorter static acquisition is used, despite its sensitivity to blood flow confounding longitudinal analysis. A method has been proposed to reduce the dynamic acquisition time for quantification by incorporating cerebral blood flow (CBF) information from arterial spin labelling (ASL) magnetic resonance imaging (MRI) into the pharmacokinetic modelling. In this work, we optimise and validate this framework for a study of ageing and preclinical Alzheimer's disease. This methodology adapts the simplified reference tissue model (SRTM) for a reduced acquisition time (RT-SRTM) and is applied to [18F]-florbetapir PET data for amyloid-β quantification. Evaluation shows that the optimised RT-SRTM can achieve amyloid burden estimation from a 30-min PET/MR acquisition which is comparable with the gold standard SRTM applied to 60 min of PET data. Conversely, SUVR showed a significantly higher error and bias, and a statistically significant correlation with tracer delivery due to the influence of blood flow. The optimised RT-SRTM produced amyloid burden estimates which were uncorrelated with tracer delivery indicating its suitability for longitudinal studies.
Biases in Charitable Giving to International Humanitarian Aid
Authors: Mittelman Robert , Dow Douglas
Published: September 2018

At a time when government support for international humanitarian aid is decreasing, organizations devoted to helping in times of disaster are looking ever more to the individual donor for financial contributions. In this paper, we explore the relationship between the donor and the distant other by introducing the concepts of psychic distance and psychic distance stimuli to the macromarketing literature and exploring the role of psychic distance in fundraising for international humanitarian aid. It is our contention that by better understanding the biases that psychic distance introduce into the system, an improved flow of donations for the betterment of the distant needy and a more effective marketing system can be achieved. We offer four propositions for future testing and exploration.
System for Controlling the Vulcanisation Characteristics of a Rubber Mix
Authors: Klimov A.N. , Sochnev G.M. , Sadchikova G.M. , Biryukov V.P.
Published: September 2018

The present authors [1–3] have shown the possibility of controlling the vulcanisation characteristics of a rubber mix by adjusting the mass doses of sulphur and sulphenamide, and have constructed a mathematical model of the controlled entity in respect of the control actions. In the present work, a linear, quadratic, stochastic controller of vulcanisation characteristics is synthesised, and, by computer modelling, under real production disturbances, its effectiveness is investigated.
Recycling of Organic Waste from Acrylate Production
Authors: Ramazanov K.R. , Afonin A.V. , Verin D.A.
Published: September 2018

An analysis was made of the composition and physicochemical properties of waste from the process of purifying mother liquors of acrylate production. The possible ways of using floating organic matter in the form of an independent boiler fuel or as a component in a mixture with combustible waste from the production of phenol and acetone, acrylic acid nitrile, and methyl methacrylate were investigated.
Rheological and Mechanical Properties of Epoxy Composites Modified with Montmorillonite Nanoparticles
Authors: Il'in S.O. , Gorbunova I.Yu. , Plotnikova E.P. , Kerber M.L.
Published: September 2018

An examination is made of the effect of modifying montmorillonite with organic compounds and its ultrasound treatment on the rheological properties of filled epoxy oligomers and the structure and physicomechanical properties of cured composites. To improve the physicomechanical properties of filled epoxy composites, it is recommended that use be made of modified montmorillonite of grade Cloisite 30B, which has the best compatibility with the epoxy matrix.
The Development of Technology for Large-Diameter, Reinforced Polyethylene Pipes of Increased Working Pressure
Authors: Biserova N.V. , Kovriga V.V.
Published: September 2018

The demand for large-diameter pressure pipes is increasing constantly. The most effective method for increasing the working pressure is reinforcement, in particular reinforcement with a glass fibre mesh. Different reinforcement variants were tested: single-layer, two-layer, and layered reinforcement. The best results were obtained using a layered design.
The Design of Composite Anisotropic Rods
Authors: Grigor'ev S.N. , Krasnovskii A.N. , Khaziev A.R.
Published: September 2018

An examination is made of the building of the applied theory of a composite anisotropic rod operating in tension accompanied with torsion. The structure of the rod consists of internal fibres, spirally oriented by slight twisting about the rod's axis, and an outer pair of spirally crossing layers. An analysis is made of the strain state of a rod loaded by an axial force, and relations are obtained for determining the displacement and turning of the end section of the rod.
Features of the Structure and Rheology of Nitrocellulose Solutions
Authors: Kostochko A.V. , Valishina Z.T. , Shipina O.T.
Published: September 2018

The latest methods – rotation viscometry, IR spectroscopy, NMR spectroscopy, gel permeation chromatography, and the turbidity spectrum method – were used to investigate the structural, rheological, and molecular properties of cellulose nitrate solutions. Results clarified the laws governing the structure formation in medium- and semidilute cellulose nitrate solutions.
The Effect of Nanofillers on the Physicomechanical Properties of Organosilicon Plastic Foams
Authors: Rybalko V.P. , D'yachenko P.B. , Nikityuk A.I. , Pisarenko E.I. , Kireev V.V.
Published: September 2018

A study was made of the possibility of using nanosized fillers for improving the physicomechanical properties of plastic foams based on organosilicon binders. The expediency is shown of using carbon nanotubes in small quantities (0.05-0.2 wt%) to increase the maximum compression strength and the compression set under maximum load.
Analysis of the Sealing Force/Elastic Recovery Behaviour of Polymers in the Cold as a Function of Molar Mass, using the Example of Fluoroelastomers
Authors: Hornig R. , Sunder J.
Published: September 2018

A relevant technical feature of an elastomeric sealing material is its sealing function in the cold down to the glass transition range. Considering homologous elastomer structures as a function of their molar mass, low-viscosity elastomeric materials offer the advantage of shorter relaxation times, giving reason to expect a more marked dynamic structural mobility and flexibility at low temperatures. Identical elastomer structures with a high molar mass and a more complex entanglement due to longer polymer chains will show more significant growth of the potential energy of the molecules by their dislocation to positions of higher energy, as well as the change in entropy, during an increase in static compression. This will be reflected by the linear pressure dependence of the specific volume, which is not significantly influenced by the molar mass, and by the decrease in the specific volume when the molar mass increases, which can be demonstrated by PVT diagrams. A chemical network structure will significantly support the elastic recovery characteristics, interfere with the physical effects but constrain the mobility of the polymer chains which can have various effects depending on the molar mass and compression state. From the mere thermodynamic viewpoint, the elastic recovery behaviour or sealing force in the cold should be supported by an increase in the molar mass of the polymer. However, if the effects are considered in conjunction, opposing behaviour can be detected, i.e. the mobility of the structure decreases and the elastic recovery behaviour improves if the molar mass of the elastomeric material is increased. This gives reason to expect that the sealing force in the cold will pass through a maximum functionality as the molar mass grows. The objective of this study was to investigate the molar mass dependency of the sealing force function at very low temperatures using the example of a range of relatively homologous fluoroelastomer grades. A description of the static measurement method used is also given.
New Anticorrosion Coatings Based on Crosslinked Copolymers of Pyrrole and Epoxy-Containing Compounds
Authors: Mezhuev Ya.O. , Korshak Yu. V. , Vagramyan T.A. , Abrashov A.A. , Piskareva A.I. , Yur'eva G.A. , Shtil'man M.I.
Published: September 2018

Anticorrosion coatings based on a crosslinked copolymer of pyrrole and glycidyl methacrylate and also a copolymer of N-vinylpyrrolidone and allyl glycidyl ether were obtained on the surface of iron and zinc. The inhibition of corrosion by polypyrrole was shown, a mechanism of the process was proposed, and the synthesis of coatings was optimised.
Composite Materials based on Polypropylene with Carbon Nanofillers
Authors: Shitov D.Yu. , Kravchenko T.P. , Osipchik V.S. , Rakov E.G.
Published: September 2018

The processing properties of a composite material based on modified filled polypropylene have been investigated.
Investigation of Cotton-Lint Cellulose using Customs Chemical Examination
Authors: Karimkulov K.M. , Askarov M.A.
Published: September 2018

Procedural recommendations have been developed for the application of customs chemical examination of cotton-lint cellulose in international economic transactions. Standard documents for cotton cellulose are given. The main parameters of cotton cellulose have been studied by determining the commercial condition, chemical composition, and fibre length, and criteria have been determined for each grade and type of cotton lint.
Reaction Modification of Recycled Polyethylene Terephthalate with 1,3-Phenylene-Bis-Oxazoline
Authors: Veselova E.V. , Andreeva T.I. , Strelkova M.V.
Published: September 2018

The introduction into recycled polyethylene terephthalate of 0.5% 1,3-phenylene-bis-oxazoline in the process of extrusion without preliminary drying makes it possible to increase the intrinsic viscosity of the material to 75 mL/g, without any change in its thermophysical properties. The existence of an induction period, during which the additive is less effective, is shown.
Injection Moulding of Durable Superhydrophobic Surfaces Made of LSR
Authors: Hopmann C. , Recht U. , Behmenburg C.
Published: September 2018

The lotus effect known from nature has so far only been successfully imitated by the incorporation of additives or by modifying the polymers used. By using microstructured moulds there is now a way to produce durable, superhydrophobic surfaces in a single-step injection moulding process. This method combines shaping and functionalisation of the part in one process step. The studies show that, by selecting suitable microstructures, an increase in the contact angle by up to 40° can be achieved. At the same time, the LSR microstructures produced show good abrasion resistance.
Investigating the Possibility of Modifying Polystyrene with Polysaccharides with the Aim of Producing Biodegradable Grades
Authors: Sadrieva A.G. , Boreiko N.P. , Trifonova O.M. , Garifutdinov M.K.
Published: September 2018

The results of modifying polystyrene with thermooxidised starch with different molecular weight characteristics are presented. An assessment is made of the influence of the additives used in different concentrations on the characteristics of the initial polymer.
Anisotropic Organic Azo- and Azoxybenzenes Exhibiting the Properties of Light and heat Stabilisers of Polyvinyl Chloride
Authors: Gavrilova A.O. , Potemkina O.V. , Kuvshinova S.A. , Kuznetsov V.B. , Koifman O.I.
Published: September 2018

The first five organic compounds of the azo- and azoxybenzene classes have been tested as light and heat stabilisers of polyvinyl chloride. Their high effectiveness by comparison with industrial antioxidant has been demonstrated.
The Effect of Uv Irradiation on the Structure and Properties at Elevated Temperature of a “Linear Polyethylene–Nanosized Silicon Dioxide” Crystallising System
Authors: Gordienko V.P. , Sal'nikov V.G.
Published: September 2018

For the case of a large-tonnage plastic (linear polyethylene) containing additions of nanosized silicon dioxide, it has been shown experimentally that thermomechanical and photochemical action on the obtained polymer nanocomposites leads to a change in the molecular and supermolecular structure of the polymer such that there is an increase in the strength of the materials at a temperature exceeding the equilibrium temperature of melting of polyethylene, and an increase in their softening point.
A Model of the Stress State in Welded Polymer Piping
Authors: Aristov V.M. , Aristova E.P.
Published: September 2018

A model of the stress state in the weld zone of a polymer construction is examined. A viscoelastic solution of the problem is obtained using the temperature–time analogy principle.
Comparative Investigations of the Influence of the Type of Catalytic System and the Polymerisation Conditions of Isotactic Polypropylene on the Yield and Properties of Atactic Polypropylene
Authors: Dakhnovskaya E.V. , Nekhorosheva A.V. , Nekhoroshev V.P.
Published: September 2018

A comparative investigation was made of the influence of the type of catalytic system and the polymerisation conditions of isotactic polypropylene on the yield and properties of atactic polypropylene.
A Theoretical Analysis of the Process of Flow of Nanocomposites of High-Density Polyethylene and Organoclay
Authors: Dibirova K.S. , Kozlov G.V. , Magomedov G.M. , Zaikov G.E.
Published: September 2018

It is shown that the process of flow of polymer/organoclay nanocomposites includes mechanical disordering of part of the crystalline phase. This process has a strong influence on the elastic modulus but has no effect on the yield point, which is the most stable mechanical characteristic.
An Investigation of the Strength of Different Layers and Welded Joints of Polyethylene Pipes by the Tearing Reinforcing Element Method
Authors: Kolbaya V.G. , Pendik S.S. , Biserova N.V. , Kovriga V.V.
Published: September 2018

A method was proposed for assessing the strength in different layers of the walls of polyethylene pipes and their welded joints from their resistance to tearing by a reinforcing element
Biocidal Compositions with Metal Nanoparticles for the Protection of Non-Metallic Materials against Microbiological Damage
Authors: Krivushina A.A. , Polyakova A.V. , Goryashnik Yu. S. , Yakovenko T.V.
Published: September 2018

On the basis of an analysis of the scientific-and-technical and patent documentation, the principal directions of development in the field of biocidal compositions with metal nanoparticles for the protection of non-metallic materials against microbiological damage are determined. Domestic and foreign technologies for protecting materials against microbiological damage with the use of nanoparticles are analysed. The long-term outlook for the use of nanoparticles of a number of metals as biocidal additives is substantiated.
The Properties of Nanocomposites Based on Styrene Plastics
Authors: Kakhramanov N.T. , Bagirova Sh.R.
Published: September 2018

An examination is made of the results of investigating the influence of the concentration of nanoparticles and graft copolymer (modifier) on the main physicomechanical characteristics of styrene plastics. The limiting concentrations of nanoparticles with which the maximum strength properties are achieved are determined. An interpretation of the mechanism of failure of filled polymer composites is given.
The Effect of Alcohol Additives on the Synthesis and Properties of a Cationic Flocculant – A Copolymer of Acrylamide and N, N-Dimethylaminoethyl Methacrylate Sulphate
Authors: Kazantsev O.A. , Shirshin K.V. , Khokhlova T.A. , Khasanov A.O. , Kamorin D.M. , Sadiov A.Yu.
Published: September 2018

It was shown that additions of glycols and PEG-600 increase the rate of adiabatic radical copolymerisation of acrylamide and N,N-dimethylaminoethyl methacrylate sulphate in aqueous solutions, while the introduction of glycerin lowers the rate of this process. Use of alcohol additives improves the technology for producing the investigated copolymeric cationic flocculant.
The Influence of the Carbon Black Morphology on the Interphase Layer Content in Filled Elastomers
Authors: Kablov V.F. , Petryuk I.P.
Published: September 2018

The strong interaction between rubber and filler leads to the formation of an interphase region at the boundary. Its properties differ from the properties of the remaining matrix, and it has a considerable influence on the properties of the elastomeric composite. The dependence of the volume fraction of interphase polymer layer φδ on the volume fraction of filler φf for particles of different shape and structure was calculated. The values of φδ for the individual particles and linear aggregates are higher than for aggregates of ellipsoidal structure. All dependences pass through a maximum at different φf: for individual particles and linear aggregates roughly at φf = 0.1, for aggregates of ellipsoidal structure at φf = 0.3. The results were compared with data on the adsorption of dibutyl phthalate by different grades of carbon black (CB) having an identical specific surface (N326, N330, N351, N358). The more CB aggregates accessible to elastomer molecules there are, the higher is φδ. Thus, CBs of chain structure have, at all φf, higher φδ values than CBs with aggregates of ellipsoidal structure. The obtained results open up the possibility of predicting the optimum content of ingredients in the elastomeric composites.
The Influence of the Acid–Base Balance of the Surface of Silica Filler Particles on the Structure and Properties of Composites Based on Nitrile Butadiene Rubber
Authors: Ovsyannikova D.V. , Solov'eva O.Yu. , Indeikin E.A.
Published: September 2018

The acid–base balance of the surface of silica filler (SF) particles of different grades was determined, and its influence on the structure and properties of mixes based on nitrile butadiene rubber (NBR) was investigated. A near-linear correlation was found between the proneness of the SF particles to flocculate and the concentration of acid centres (ACs) on their surface, in the absence of any pronounced influence on this index of the degree of dispersion of the filler particles. Of all the SF grades investigated, the greatest capacity to form flocculation structures is exhibited by a filler characterised by a higher SF concentration. Increase in the SF concentration leads to an increase in the relative content of physical and covalent bonds in binary mixes of NBR and SF. It is shown that, to reduce the negative effects associated with the formation of flocculation structures, including in the induction period of vulcanisation, it is necessary to select a filler with a lower concentration of these centres.
The Physicomechanical and Rheological Characteristics of Wood–polymer Composites Based on Thermally and Mechanically Modified Filler
Authors: Volfson S.I. , Fayzullin I.Z. , Musin I.N. , Fayzullin A.Z. , Grachev A.N. , Pushkin S.A.
Published: September 2018

The effect of different wood fillers on the physicomechanical and rheological properties of wood–polymer composites was studied. It was shown that thermal and mechanochemical modification of wood flour has a considerable effect on the properties of wood–polymer composites.
Carbon Nanotubes in Tyre Rubbers. Part 2: A Study of the Effect of Nanotubes on the Properties of Carbon-black-filled Tread Rubbers
Authors: Mukhtarov A.R. , Mokhnatkin A.M. , Dorozhkin V.P. , Mokhnatkina E.G. , Muradyan V.E. , Batrshina R.R.
Published: September 2018

The processing and mechanical properties of green and vulcanised tread rubbers based on a blend of two types of styrene butadiene rubber filled with carbon black and containing single-layer carbon nanotubes (SCNTs) were studied. Three types of rubber mix were prepared: one containing untreated SCNTs and stearic acid, and two with SCNTs treated by different methods. The properties of these composites were compared. In all cases, the introduction of SCNTs leads to an increase in the cohesion strength of green rubber mixes, to an improvement in their vulcanisation properties, and to an increase in the Mooney viscosity, and also to an improvement in the dynamic properties of the vulcanisates, and here the Payne effect increases. There is also an improvement in the wear resistance, especially in the case of introducing untreated SCNTs and stearic acid which ensures the presence of –COOH groups.
An Approach to Analysing the Influence of the Chemical Structure of the Solvents and their Concentration on the Glass Transition Temperature of the Polymer for Systems Containing a Polymer and Two Solvents
Authors: Matseevich T.A. , Kurskaya E.A. , Kovriga O.V. , Askadskii A.A.
Published: September 2018

A scheme has been developed for calculating the glass transition temperature of a system containing a polymer and two different solvents. Account is taken of the chemical structure of the polymer and solvents (one of them may be a plasticiser), the intermolecular interaction between the polymer and solvents, and also between the solvents themselves, the van der Waals volume of the repeating unit of the polymer and molecules of both solvents, and their concentration.
Resistance to Thermal Oxidation of Ethylene Propylene Rubber and Polyhydroxybutyrate Blends
Authors: Ol'khov A.A. , Shibryaeva L.S. , Tertyshnaya Yu.V. , Kovaleva A.N. , Kucherenko E.L. , Zhul'kina A.L. , Iordanskii A.L.
Published: September 2018

The structure, properties, and kinetics of thermal oxidation of blends based on polyhydroxybutyrate (PHB) and ethylene propylene rubber (EPR) were studied. The physicomechanical properties were studied using a ZE-40 tensile testing machine (Germany), and the crystallisation temperature Tcr and melting temperature Tm of PHB in the blends were determined on a DSM-2M differential scanning calorimeter at a scanning rate of 16°C/min. The morphology of films was determined by scanning electron microscopy on a Hitachi S-570 microscope (Japan). The kinetics of thermal oxidation of the blends was assessed according to the amount of absorbed oxygen. With increase in the PHB content in the blend there is a reduction in the elongation at break and an increase in the tensile strength and modulus. Change in the PHB content and in the oxidation time leads to negligible changes in Tcr and Tm. It was established that the greatest reactivity of blends in relation to oxygen is observed in the range of PHB concentrations of 20–40%, where the greatest phase interface area is formed. It was shown that, by changing the ratios of EPR and PHB, it is possible to control the kinetics of thermal oxidation of the blends. It was shown that, in the range of concentrations of 50–70% PHB, phase inversion occurs in the blends.
Features of the Abrasive Wear of Rubbers Containing Complex Anti-ager PRS-1N
Authors: Puchlov A.F. , Spiridonova M.P. , Lapin S.V. , Kiba A.A.
Published: September 2018

An MIR-2 machine and an MBI-3 light microscope were used to study the abrasive wear of tread rubber containing a complex anti-ager, antidegradant PRS-1N, in comparison with a rubber containing anti-ager IPPD (N-isopropyl-N-phenyl-p-phenylenediamine). Rubber containing PRS-1N (∊-caprolactam-N-isopropyl-N-phenyl-p-phenylenediamine-zinc disalicylate) has considerably less wear. The reason for this is the presence of ∊-caprolactam in PRS-1N and its interaction with other components of the complex anti-ager. Data on washing out confirm this interaction. An important role is played by the polarity of PRS-1N, which leads to its incompatibility with general-purpose rubbers entering the composition of tread rubber. Deliberations concerning the mechanism of action of antidegradant PRS-1N are presented.
Rubber Mixes: Experience in Database Development
Authors: Drabkin S.S.
Published: September 2018

The ‘Rubber mixes’ program package has been developed on the basis of Microsoft Access 2010. Its functional possibilities are as follows: (1) the search for a specific grade to look up all the characteristics of the rubber mix; (2) the search for a specific specification (TU) or other documentation to look up the composition of the TU, and also the properties of the mixes contained in the TU (depending on the classification adopted in the TU, there are two types of form – according to rubber type or according to rubber mix designation); (3) a comparative analysis of rubber mixes with respect to a single property; (4) the search for a rubber mix with several prescribed parameters, for example: the type of rubber, the working medium and the temperature range, the tensile strength, the elongation at break, the hardness, the cold resistance coefficient, and the brittle point; (5) the formation of different reports. A brief description is given of developed forms. The creation within the industry of a Unified Classifier of Rubber Mix Use Designations is proposed.
The Design of Composite Materials of Prescribed Structure and Properties
Authors: Koroteeva L.I. , Sharonov A.V. , Astakhov P.A. , Mironov N.A. , Sergeeva A.V.
Published: September 2018

The structure and properties of a composite material (basalt-fibre-reinforced plastic) reinforced by chaotically distributed discrete fibres were determined at the design stage with account taken of the fibre diameter, the critical length of the fibres, the arrangement of fibres within the matrix, and the stress distribution over the length of the fibres. The results of calculation were used in the manufacture of specimens of thermoplastic polymeric material by the developed technology. The given results of experimental investigation of specimens of the thermoplastic material showed that the calculated values of the properties of the composite differ little from experimental values.
Radio-absorbent Material Based on Polyvinyl Chloride Filled with Disperse Carbon Fibre
Authors: Vlasenko E.A. , Bokova E.S. , Dedov A.V. , Devin K.L.
Published: September 2018

The influence of the content of plasticiser and disperse carbon fibre on the radiophysical characteristics of filled film radio-absorbent materials is investigated.
The Influence of Processing Additives on the Properties of Glass-fibre-reinforced Composites Based on Biobased Polyamide 1010
Authors: Nikiforov A.A. , Vol'fson S.I. , Okhotina N.A. , Rinberg R. , Kroll L.
Published: September 2018

The results of investigating the influence of processing additives from a group of lubricants on the degree of comminution of glass fibres during extrusion and the properties of composites based on biobased polyamide 1010 with different degrees of filling with chopped glass fibre are presented.
Targeted Solidification through Self-optimising, Highly Segmented Mould Temperature Control in Injection Moulding
Authors: Hopmann C. , Schmitz M.
Published: September 2018

The precision of manufactured parts is one of the most important quality criteria in mass production processes. While for mechanical machining processes high-precision parts can be achieved by using CNC techniques and high-precision machining, melt-based production processes still have large precision drawbacks, which can only be compensated by time-consuming mould trial iterations or post-processing. The following article discusses a new approach to incorporating a segmented temperature control system in an injection mould, leading to a processing technique which is capable of local adjustment of the part temperature. This segmented local temperature control, which is based on appropriate heating and cooling techniques and a novel control approach, is designed to have a positive effect on the solidification of the melt and shrinkage of the plastics part in order to achieve minimal part warpage. This process control is extremely demanding in terms of temperature control techniques, process measurements and control strategies, which are discussed below. Firstly, temperature control techniques that are able to deliver high performance and allow the most dynamic control of the part's surface temperature are discussed and evaluated. To control this process effectively, various sensors are analysed which are capable of measuring real part temperatures within the process runtime. Finally, the requirements for a control concept that allows efficient control of mould temperature are discussed, taking account of high dead times.
Predicting the Dynamic Characteristics of Vibration-isolating Rubbers Based on Natural and Synthetic Rubbers
Authors: Myslivets M.N. , Yurtsev L.N. , Zhenevskaya E.E. , Tolstov A.M.
Published: September 2018

The principal vibration-isolating characteristics of rubbers based on natural rubber and a combination of synthetic isoprene and butadiene rubbers were determined. The static and dynamic moduli, the hysteresis losses, and the logarithmic decrement were measured on an Yerzley mechanical oscillograph (manufactured by the US company Tavdi) in accordance with ASTM D-945. The changes in these characteristics were measured in the process of heat ageing. To convert the data to room temperature, the Arrhenius equation was used. The main changes in the static modulus occur in the first three years, and the main changes in the dynamic modulus in the first five years. Their ratio and the natural frequencies are different for various rubbers and for different storage and service times. The resonance zones are also different. It is concluded that, when predicting the useful life of the vibration isolator, it is necessary to assess all the dynamic and static parameters for each individual case.
The Use of Reactions of Metathesis Polymerisation of Cyclic Olefins for the Production of a Dicyclopentadiene Polymer
Authors: Sharifullin I.G. , Akhmetov I.G. , Kubanov K.M. , Sofronova O.V. , Alekseeva A.P.
Published: September 2018

The results of a literature study of methods for producing polydicyclopentadiene (PDCPD) by the metathesis polymerisation of cycloolefins are given. Approaches to forming the components of the catalytic system are studied with the aim of creating a process for the production of PDCPD by reaction injection moulding technology using as far as possible Nizhnekamskneftekhim's own raw material. The present state and the prospects of the industrial production and consumption of PDCPD in Russia and in member countries of the CIS are considered.
Heterorganic Fire-resistant Coatings for Artificial Fibres
Authors: Izmailov B.A. , Komarova L.G. , Rodlovskaya E.N. , Markova G.D. , Vasnev V.A. , Rudakova T.A. , Amelichev A.A. , Novikova N.S.
Published: September 2018

A method has been developed for producing fire-resistant phosphorus- and nitrogen-containing organosiloxane coatings on the surface of cellulose fibres. It has been shown that such a three-layer coating ensures an increase in the oxygen index of the fibres from 20 to 47%.