Back SearchTitle: PLATE OUT - MORE THAN JUST A PHENOMENON? PART 2. PLATE OUT IN THE EXTRUDER
Page Range: T/1-8
Author(s): Gilbert M; Haberleitner R; Schiller M; Varshney N; Walon M
File size: 318K
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Issue Year: ipsat
Volume: 31
Issue No: No. 6
Abstract
The methods for the formation of plate-out in the extruder are postulated, and a method is described for the reliable determination of the plate-out behaviour of waxes and metal soaps. Extensive experimental work in the field of plate-out is reported, and the investigations provide information on the processing window for waxes. As such the proposed method may be used to predict the influence of the formulation and processing within a specific range. Reference is made to the work of Lippoldt which states that the mechanisms for the formation of plate-out is based on the fact that lubricants and metal soaps are only restrictedly soluble in a PVC melt. The role is investigated of polyurethane waxes, calcium stearate, neutral lead stearate and the melt temperature in the formation of plate out in the die. Taking into account the compatibility investigations, the Lippoldt mechanism may be considered to be confirmed and also found valid for lead-stabilised systems as well as tin stabilisers. 9 refs. (Article translated from Gummi Fasern Kunststoffe, No. 2, 2004, pp. 106-11.)
Title: IMPROVEMENT OF PROPERTIES OF THERMOPLASTICS BY REINFORCEMENT WITH LONG GLASS FIBRES
Page Range: T/9-14
Author(s): Bernd H; Wunder H
File size: 233K
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Issue Year: ipsat
Volume: 31
Issue No: No. 6
Abstract
The potential for use of long glass fibre reinforcement in engineering thermoplastics is discussed, with particular reference to Celstran materials. The criteria for the choice of base material are examined, and particular details are given of the long term heat resistance in air, resistance to chemical media, effect of fibre orientation, notched impact strength, warping behaviour, and behaviour under dynamic loading. (Article translated from Muanyag Gumi, No. 1, 2004, pp. 11-5.)
Title: SURFACE MODIFICATION OF ARTICLES MADE FROM ULTRAHIGH MOLECULAR WEIGHT POLYETHYLENE
Page Range: T/15-20
Author(s): Tsvetkova E A
File size: 299K
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Issue Year: ipsat
Volume: 31
Issue No: No. 6
Abstract
The use of UHMWPE in the endoprosthetics of joints is discussed, with reference to the properties which make it suitable for this applications such as total hip joint endoprostheses (THJEs). In order to solve the current problems of wear, and to create implants capable of simulating the structural features of living tissue, the creation on the friction surface of the polymer insert of the THJE, of a microporous transition layer, is investigated. Certain technological features of formation of a microporous structure on the surface of articles made from UHMWPE are considered in this article. Medical Vaseline oil was used as the modifier for UHMWPE. 19 refs. (Article translated from Plasticheskie Massy, No. 8, 2003, pp. 37-40.)
Title: ORGANIC LIGHT FILTERS BASED ON COPOLYMERS OF FLUOROALKYL METHACRYLATES CONTAINING COPPER AND COBALT SALTS
Page Range: T/21-24
Author(s): Koryagina E L; Arkhireev V P; Volkova T A
File size: 53K
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Issue Year: ipsat
Volume: 31
Issue No: No. 6
Abstract
Organic light filters are noted for a great variety of spectral characteristics owing to the possibility of introducing different light-transmitting additives into the polymer matrix. However, a serious obstacle to the effective use of such light filters is the inadequate resistance of their spectral characteristics under conditions of the action of different external factors. The development therefore, of polymeric light filters with stable optical properties is the focus of this article. New copolymers of fluoroalkyl methacrylates containing as light transmitting additives, copper and cobalt salts were investigated as possible use as light filters with stable spectral characteristics. This work includes a study of how the optical characteristics and also the photo and heat resistance of fluoroalkyl methacrylates with copper and cobalt salts are influenced by the chemical structure of the polymer matrix, the nature of the anion of the salt, and the concentration of the salt. 8 refs. (Article translated from Plasticheskie Massy, No. 8, 2003, pp. 41-3..
Title: METHODS FOR MANUFACTURING CARBAMIDE POLYMER-CONCRETE ARTICLES
Page Range: T/25-27
Author(s): Karabaev A M
File size: 48K
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Issue Year: ipsat
Volume: 31
Issue No: No. 6
Abstract
In order to accelerate the strength gain of polymer concrete based on carbamide-formaldehyde resins, the concrete is subjected to different methods of heat treatment, brief details of which are given. The main focus of the article is the different methods for the manufacture of carbamide polymer-concrete articles, and test results for each are given in terms of compressive and bending strengths, resistance to chemicals and water, shrinkage, and coefficient of resistance after storage. It was established that internal stresses have a considerable influence on the processing parameters of vibration forming, the curing temperature, the rate of rise and fall of temperature curing, etc., and with account taken of these factors, a method was developed for the manufacture of large polymer-concrete articles which resulted in an increase in strength and in the coefficient of resistance in drinking water, in mineralised water, in acids and in alkalis, and also in a reduction in shrinkage and in water absorption. 6 refs. (Article translated from Plasticheskie Massy, No. 8, 2003, pp. 44-5.)
Title: CARBON FIBRE REINFORCED PLASTICS AS PRECURSOR BASE MATERIALS FOR CARBON-CERAMIC COMPOSITES FOR IMPROVING THE EXTERNAL EROSION-PROOF PROTECTION OF SPACE SHUTTLES
Page Range: T/28-35
Author(s): Kostikov V I; Kolesnikov S A; Bukharov S V
File size: 138K
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Issue Year: ipsat
Volume: 31
Issue No: No. 6
Abstract
The use is discussed of carbon fibre-reinforced plastics as precursor base materials for carbon-ceramic composites for application to space shuttles as a protective coating, capable of providing a thermal shield. Technological problems relating to the development of such products include the creation of constructional thin-walled coatings of carbon-carbon composites of approximately 3 mm, with relatively large segmental surfaces each up to 2-3 square metres in area, to prevent any significant increase in weight of the craft. This article concerns itself with addressing technological problems of creating thin-walled, large surfaces of carbon-carbon composites with anti-oxidative and anti-erosion protective coatings; the physiochemical problems of creating large carbon-carbon feedstock of stable geometric shapes on the basis of carbon fibre-reinforced plastic precursor feedstock; and the physicochemical problems of ensuring stability of the geometry of large thin-walled sheets during the formation of ceramic components of the matrix and the anti-oxidative erosion-proof coating. The technical creation of such coatings with satisfactory specific weight characteristics in the form of large thin-walled parts is shown to be possible with the additional optimisation of the selection of the polymer binders at the first stages of forming of feedstock and optimisation of the construction of parts with account taken of the mechanics of carbonisation and other high-temperature production processes. 14 refs. (Article translated from Plasticheskie Massy, No. 9, 2003, pp. 12-7.)
Title: FEATURES OF THE PROCESS OF CURING OF THERMOSETTING API IMIDE BINDERS
Page Range: T/36-45
Author(s): Miichenko I P
File size: 127K
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Issue Year: ipsat
Volume: 31
Issue No: No. 6
Abstract
This work attempts to analyse the chemorheological behaviour of curing imide binders API, noted for their high level of working temperature. Use of the main theoretical positions recently developed, has made it possible to reveal both the correspondence and the difference in behaviour of imide compositions of the API type from the behaviour of model (mainly epoxy) systems. The rigid-chain structure of the inter-crosslink units in the crosslinked polyimide, the low concentration, and the complex structure of crosslinked points are shown to have a considerable influence on the nature of the kinetic and equilibrium diagrams. During the investigation of complex-composition, i.e. heterophase, systems, it was found that the behaviour of each of the phases is reflected on the equilibrium and kinetic diagrams. In this present case, it was difficult to interpret sufficiently the diagrams obtained, but it is argued that this does not prevent their practical use. However, it is said to be more convenient to use nomograms of the chemorheological states of matrix systems. 25 refs. (Article translated from Plasticheskie Massy, No. 9, 2003, pp. 22-8.)
Title: METHODS FOR LOWERING THE RESIDUAL STRESSES OF CARBON FIBRE REINFORCED API IMIDE PLASTICS
Page Range: T/46-50
Author(s): Miichenko I P; Kostyuchenko V N
File size: 48K
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Issue Year: ipsat
Volume: 31
Issue No: No. 6
Abstract
A series of tests are described, which show that to produce carbon fibre-reinforced polyimides with a reduced level of residual stresses, i.e. with increased working capacity under mechanical load, it is necessary in the production of plastics to use elasticisation of the API matrices and, after moulding, to conduct additional heat treatment at temperatures equal to or above the moulding temperature. A reduction in the stress state of the structure increased the shear characteristics of carbon fibre-reinforced imide plastics based on API matrices. 7 refs. (Article translated from Plasticheskie Massy, No. 9, 2003, pp. 29-31.)
Title: EFFECT OF AGEING OF A POLYAMIDO ACID SOLUTION AND THE CONDITIONS OF ITS IMIDISATION ON THE STRUCTURE AND PROPERTIES OF THIN POLYIMIDE FILMS
Page Range: T/51-55
Author(s): Babaevskii P G; Kozolov N A; Zhukov A A; Zhidkov S A; Ruzhitskaya O V
File size: 74K
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Issue Year: ipsat
Volume: 31
Issue No: No. 6
Abstract
Thin thermally stable, heat resistant aromatic polyimide films are used in the production of miniature actuators and transducers of microsystem technology. Methods for the production of such films are mainly based on the flow of unstable solutions of polyamido acid (PAA) solutions in strongly polar solvents on a solid surface, drying of the solutions, thermal imidisation of PAA, and separation of the film from the substrate. The structure and properties of the films are influenced most by the prehistory of the PAA solution and the conditions of imidisation after application onto the substrate. The ageing of PAA solutions, including those based on pyromellitic acid dianhydride and 4,4'-oxydianiline (PMDA-ODA) in dimethylacetamide (DMA), has previously been investigated and connected both with chemical and physical transformations of PAA in solution. However, there have been no systematic investigations of the effect of ageing during storage of a PAA solution based on PMDA-ODA in DMA, and the conditions of its imidisation on the structure and properties of thin polyimide films, which is the focus of this present work. The ageing is characterised by two physicochemical processes: in the first (up to 35 +/- 5 days), the properties and structure are influenced predominantly by the irreversible process of hydrolysis of PAA and during the second stage (over 35+/- 5 days), by the process of change caused by partial imidisation leading to the formation of denser macromolecular coils with their possible conversion into globules. These processes lead to a reduction in the elastic modulus and strength of thin polyimide films obtained under optimum imidisation conditions. However, the breaking elongation and the coefficient of water vapour permeability change comparatively little in this case. 11 refs. (Article translated from Plasticheskie Massy, No. 9, 2003, pp. 31-4.)
Title: FIBRE TECHNOLOGY FOR THE PRODUCTION AND PROCESSING OF THERMOPLASTIC COMPOSITES
Page Range: T/56-64
Author(s): Golovkin G S
File size: 82K
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Issue Year: ipsat
Volume: 31
Issue No: No. 6
Abstract
A review is presented of developments in fibre technology for the production and processing of thermoplastic composites. The problems that fibre technology has been called upon to resolve are primarily the guarantee of low-porosity (1-3 vol. %) impregnation of fibre reinforcing elements by high-viscosity melts and solutions of high-molecular weight thermoplastic binders, increase in the volumes of reinforcement of reinforced thermoplastics above the previously achieved 50-70 vol. %, and increase in the coefficients of realisation of the physicomechanical properties of the reinforcing phase of the reinforced thermoplastics. The most important specific features of synthetic fibres are detailed, and the main scientific results are examined. The article then goes on to consider the development and application of thermoplastic composite semi-finished products with the solid-phase combination of reinforcing and matrix fibres; the creation of new types and classes of thermoplastic composites; progress in methods and facilities for the production and processing of thermoplastic composites; and finally, details of the participants in the development of the scientific direction. (Article translated from Plasticheskie Massy, No. 9, 2003, pp. 35-9.)
Title: HEAT-RESISTANT JOINTS OF CARBON MATERIALS WITH PHENOL-FURFURAL-FORMALDEHYDE ADHESIVES
Page Range: T/65-67
Author(s): Sosunov S A; Komarov G V; Bukharov S V; Kravetskii G A
File size: 57K
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Issue Year: ipsat
Volume: 31
Issue No: No. 6
Abstract
Adhesives based on phenol-furfural-formaldehyde adhesives have been developed for the bonding of heat resistant joints of carbon materials. Since the service temperature of articles can reach 1500 - 2000 degrees C, the adhesively bonded joints must also be capable of withstanding such high temperatures. This work considers the development of adhesives capable of being cured at normal temperatures. The main criteria for the selection of the binder base for the adhesive were: a high yield of solid pyrolysis product of the binder; a good bonding capacity in relation to carbon materials at the initial stage and in the process of pyrolysis; together with the ability to be cured at normal temperatures. Such conditions were found to be satisfied by phenol-formaldehyde resins and furan resins. In this work, the bases used for the adhesives were resol phenol-formaldehyde resin, furan-acetone monomer, phenol-furfural-formaldehyde resin, novolac phenol-formaldehyde resin, and titanium- and silicon-containing phenol-formaldehyde resins of novalac type SF-294. The adhesive developed can be used for assembling and repairing articles manufactured from carbon materials and operating at temperatures up to 600 degrees C. 3 refs. (Article translated from Plasticheskie Massy, No. 9, 2003, pp. 40-1.)
Title: COMPUTER SIMULATION OF THE PRODUCTION OF ARTICLES FROM THERMOPLASTIC COMPOSITES
Page Range: T/68-72
Author(s): Dmitrenko V P; Gorbachev S I; Bulychev S N
File size: 88K
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Issue Year: ipsat
Volume: 31
Issue No: No. 6
Abstract
Details are given of a new and effective software, which has been developed for automation of the selection of the optimum regimes for the moulding of thermoplastic composite articles from textile semi-products obtained by fibre technology, and for computer simulation of the thermophysical and mechano-rheological processes occurring during monolithisation. As a result of the conducted industrial certification of the proposed software package, it has been possible to reduce the time of preparation of production by at least 50%, to increase significantly the flexibility of production, and to reduce the labour requirement. An example of its use is described for the calculation of the facing of a three-ply panel consisting of seven layers of organoplastics. 11 refs. (Article translated from Plasticheskie Massy, No. 9, 2003, pp. 44-7.)