Showing papers in "International polymer science and technology in 2014"
10 citations
TL;DR: In this article, the results of theoretical investigation of fibers impregnation in manufacturing high filled composite by pultrusion are represented and a criterion is the maximum intention of technologic...
Abstract: In this article the results of theoretical investigation of fibers impregnation in manufacturing high filled composite by pultrusion are represented. A criterion is maximum intention of technologic...
6 citations
TL;DR: In this article, the effect of bisoxazoline on the molecular weight, viscosity, and thermophysical characteristics of recycled polyethylene terephthalate in the process of processing without preliminary drying was investigated.
Abstract: An analysis of the scientific technical and patent literature showed that biand polyfunctional compounds, capable of reacting with the terminal groups of polyethylene terephthalate (PET), are used as polymer chain modifiers. Dianhydrides, bis-oxazolines, diepoxides, etc., are used as chain extenders [1-8]. Earlier, investigations were carried out on the modification of recycled polyethylene terephthalate (RPET) with pyromellitic dianhydride (PMDA). It was shown that the use of a PMDA concentrate based on PET ensures an increase in the molecular weight and viscosity of the melt during the processing of RPET without its preliminary drying [9]. Bis-oxazolines are likewise effective chain extenders capable of reacting with the terminal carboxyl groups of PET [10] (Scheme 1). It was of interest to investigate the effect of bis-oxazoline on the molecular weight, viscosity, and thermophysical characteristics of recycled polyethylene terephthalate in the process of processing without preliminary drying.
6 citations
TL;DR: A brief outlook on how methods from advanced control technology can support and improve production processes, e.g. in the plastics technology sector is given.
Abstract: With the ambitious forward-looking project “Industry 4.0”, the German government is promoting the computerisation of traditional industry as we know it today. Among other things, the factory of the future will automatically adapt to fluctuating requirements and increase its resource efficiency. An essential element of these developments is the systematic establishment of additional control loops. These control loops can be machine-oriented, ensuring as part of process control that the process stays reliably within predefined states. In addition, higher-level control loops, e.g. in the form of quality control loops, can adjust machine parameters as a function of the product quality required. In all cases, control technology promotes automatic and reproducible production. This paper gives a brief outlook on how methods from advanced control technology can support and improve production processes, e.g. in the plastics technology sector.
5 citations
TL;DR: In this article, the effect of using a mixture of aluminium and magnesium hydroxides on the physicomechanical, processing, and service properties of plasticised PVC materials is studied.
Abstract: One of the leading places in the total volume of production and consumption of plastics belongs to polyvinyl chloride (PVC). However, an important factor holding back the use of plasticised PVC materials is their fire hazard. When they burn, composite PVC materials and products containing plasticisers are characterised by high smoke formation and a high flame propagation rate, and therefore one of the most important problems is to lower their fire hazard [1]. In practice, the required combinations of properties is achieved by introducing different fireproofing agents into the composition of the composites. As effective fireproofing agents, aluminium and magnesium hydroxides are used most widely, the fireproofing efficiency of the hydroxides being directly proportional to their content in the polymer [2, 3]. In comparison with aluminium hydroxide, the enthalpy of breakdown of magnesium hydroxide is almost 20% higher. Their initial breakdown temperatures also differ: 250°C for aluminium hydroxide and 330°C for magnesium hydroxide [4]. The best variant for improving the fire safety of PVC material is the use of a mixture of the given fireproofing agents. Meanwhile, the introduction of these fireproofing agents can have a considerable influence on the physicomechanical properties and thermal stability of the polymeric material [5, 6]. Of special importance is the study of the effect of aluminium and magnesium hydroxides on the thermal stability of PVC materials, as the given polymer breaks down fairly readily under heat loads [7]. In connection with the above, to optimise the formulations of PVC composites, it is of interest to study the effect of using a mixture of aluminium and magnesium hydroxides on the physicomechanical, processing, and service properties of plasticised PVC materials.
5 citations
TL;DR: In this paper, the authors describe the methodology and interpretation of stability tests as commonly applied when testing elastomers and show that traditional compatibility screening does not adequately reproduce the operating conditio...
Abstract: Methodology and interpretation of stability tests as commonly applied when testing elastomers are described. Traditional compatibility screening does not adequately reproduce the operating conditio...
5 citations
TL;DR: In this article, the main and generalised structural parameters of PFPCs with hollow glass microspheres are presented, and the characteristics of Russian-industry-produced hollow glass nano-spheres of grade MS-VP-A9 are given, and generalized structural parameters for different PFPC groups are calculated.
Abstract: For the first time, data are presented on the main and generalised structural parameters of particulatefilled polymer composites (PFPCs) with hollow glass microspheres. The characteristics of Russian-industryproduced hollow glass microspheres of grade MS-VP-A9 are given, and generalised structural parameters for different PFPC groups, which determine their processing and service properties, and also the choice of an effective processing method, are calculated.
5 citations
5 citations
4 citations
TL;DR: In this paper, an examination of the mechanism of charge mozaic formation on the surface of a polycrystalline metal particle is made, and it is shown that two particles in contact with each other, owing to the presence of a potential barrier between them, acquire electric charges of different sign.
Abstract: An examination is made of the mechanism of charge mozaic formation on the surface of a polycrystalline metal particle. It is shown that two particles in contact with each other, owing to the presence of a potential barrier between them, acquire electric charges of different sign. This effect must be taken into account when assessing the adhesion, adsorption, tribotechnical, and other service characteristics of metal-polymer systems.
4 citations
TL;DR: In this paper, the production of materials based on mixtures of three different resins and the application of the obtained materials as electrets is proposed, and the results show that these materials can be used for electrets.
Abstract: The production of materials based on mixtures of three different resins and the application of the obtained materials as electrets are proposed.
TL;DR: In this paper, the compositional inhomogeneity of the obtained copolymers is determined by the overall initial monomer concentration and the structure of the ester, while the structures of the amides, replacement of the solvent, and variation of the initiator concentration have little effect on compositional heterogeneity.
Abstract: The “special” nature of the copolymerisation of higher N-alkyl acrylamides of different structure with n-dodecyl acrylate or n-docecyl methacrylate in butyl acetate or toluene is shown. It has been found that the compositional inhomogeneity of the obtained copolymers is determined by the overall initial monomer concentration and the structure of the ester, while the structure of the amides, replacement of the solvent, and variation of the initiator concentration have little effect on compositional inhomogeneity.
TL;DR: In this paper, a cyclopentadienyl dicarbonyl iron dimer [CpFe(CO)2]2 in combination with an organohalogen compound is shown to be an effective initiator/regulator of the polymerisation of vinyl chloride at t
Abstract: It is shown that a cyclopentadienyl dicarbonyl iron dimer [CpFe(CO)2]2 in combination with an organohalogen compound is an effective initiator/regulator of the polymerisation of vinyl chloride at t
TL;DR: In this paper, an analysis is made of the main known approaches to modelling the kinetics of desorption of plasticisers from polyvinyl chloride under different service conditions, including counterflow of extractant into the polymer and its influence on the modelling of extraction kinetics.
Abstract: An analysis is made of the main known approaches to modelling the kinetics of desorption of plasticisers from polyvinyl chloride under different service conditions The specific nature of extraction of plasticisers under conditions of counterflow of extractant into the polymer and its influence on the modelling of extraction kinetics are shown The effectiveness of empirical and mathematical models for predicting the kinetics of extraction of plasticisers is considered The limited nature of their application is noted, and some reliability of their use only for predicting a certain proportion of plasticisers is shown A model is developed for predicting the kinetics of different stages of extraction, reflecting the different rates of the process and comprising a power-law function The temperature dependence of the coefficient of the proposed empirical equation is shown
TL;DR: In this article, the chemical reactions taking place during ageing are very complex as a result of interactions between interactions between molecules, which is one of the important factors limiting the lifetime of elastomer products.
Abstract: Oxidative ageing is one of the important factors limiting the lifetime of elastomer products The chemical reactions taking place during ageing are very complex as a result of interactions between
TL;DR: Anticorrosion coatings based on a crosslinked copolymer of pyrrole and glycidyl methacrylate were obtained on the surface of iron in this paper.
Abstract: 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...
TL;DR: In this paper, the effect of thermoplastic modifiers on the kinetics of curing of the epoxy binder was studied. And the kinetic and diffusion constants of the curing process were determined.
Abstract: A study was made of the effect of thermoplastic modifiers on the kinetics of curing of the epoxy binder The kinetic and diffusion constants of the curing process were determined
TL;DR: The most important task in making a polymer material flame retardant is to understand its combustion behaviour and to study and analyse the mechanisms involved in flame retardancy as discussed by the authors. But flame retardants are not suitable for all applications.
Abstract: The most important task in making a polymer material flame retardant is to understand its combustion behaviour and to study and analyse the mechanisms involved in flame retardancy. The first of these reviews looked at the background to the development and application of flame retardant polymer materials with particular reference to flammabil ity standards and environmental safety regulations. This second review examines the combustion behaviour of polymer materials and basic technology of flame retard ancy mechanisms, along with recent trends in research.
TL;DR: In this paper, the authors propose a method to solve the problem of "missing links" in the context of in-situ in-vehicle collision avoidance, using the concept of "In-Situ In-Vehicle Collision Avoidance".
Abstract: ゴム分子間を結ぶ架橋点の導入により三次元的な網目構 造を形成させる架橋反応過程は,ゴムの大きな特長である ゴム弾性を発現する上で不可欠である.実用上は,所定の 加熱温度での架橋反応の進行に対応した,図1に示すよう な力学物性(周期的な一定振れ角条件下で発生するトルク) 値の変化(架橋曲線)をモニターすることで,適正な架橋 反応時間の設定の目安としている.また上述の架橋曲線 の評価以外で架橋反応を動的に追跡する手法(in-situ測定) として,接着剤(熱硬化性樹脂)や高分子ゲルの架橋反応 の各種モニタリング方法 と同様に,ゴムの架橋過程に おける各種物性測定(例えば,電気特性 ,熱特性, 超音波特性,NMR緩和特性)や発生ガスの化学分析 (連続測定),小角X線散乱法による構造解析(時分割 測定),などの応用が検討されている.しかしながら, 架橋反応をより直接的に,かつ反応の進行(反応速度)を 定量的に見積もる手法は未だ確立されていない.一方,近 年の高分子材料(ゴム,樹脂)を含めた材料科学分野にお いて,大型放射光施設の高輝度X線を利用した精密な結 晶構造解析,さらに外部刺激による構造変化のその場観察 (時分割測定)が活発に行われている.それらの取り組み
TL;DR: In this paper, the role of fillers in the formation of elastic hysteresis properties of rubber was investigated under harmonic dynamic loading conditions, i.e. under conditions similar to their service conditions.
Abstract: At present, in the manufacture of modern polymer composite materials, of special value is information about the structural transformations when optimising their composition [1] and manufacturing technology [24]. Under conditions similar to their service conditions, i.e. under harmonic dynamic loading, the elastic hysteresis properties of rubbers are characterised by the mechanical loss tangent tg δ and the components of the complex modulus E* = [(E′′)2 + (E′)2]0.5 [5]. Owing to their relaxation nature, they depend on the frequency of action of force and temperature. As a rule, in the region of low temperatures up to the glass transition temperature Tg of the polymer, they are determined mainly by the microstructure of the polymer in the rubber, while in the region above Tg the role of the active filler of the rubber predominates. Thus, the use of dynamic methods makes it possible not only to obtain absolute values of the dynamic mechanical moduli of the materials but also to clarify the role of the filler in relaxation processes of the investigated polymer composite material in a wide range of temperatures and oscillating load frequencies, which is of scientific and practical interest. Investigations of the role of fillers in the formation of the elastic hysteresis properties of rubbers under conditions of harmonic dynamic stress have been generalised in monographs [5, 6]. The revealed trends of change in tg δ of rubbers as a function of certain properties of the carbon black filler are shown in Figure 1. The blue line shows an even-sided hexagon, to each angle of which there nominally corresponds a certain property of the carbon filler of the rubbers. With increase in the value of the given properties, there is a reduction or increase in tg δ of rubbers with this filler, as shown on the deformed hexagon. The main reasons for the observed changes in tg δ is change in the elasticity or viscosity of the rubbers and the heat generation as a result of friction of the filler particles in the rubber. Thus, increase in the area of the phase interface of carbon black in the rubber, as and in the degree of branching of the primary aggregate in space and the degree of dispersion of the filler, leads to an increase in tg δ of rubbers on account of convergence of the filler particles and increase in internal friction in the material. On the other hand, increase in the activity of the carbon surface in relation to the rubber macromolecules leads to the formation of many adsorption bonds between the polymer network and structural network of the filler,