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Showing 1 to 20 of 26 for “"670 Manufacturing"”.
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Dynamic stiffness and damping prediction on rubber material parts, FEA and experimental correlation
The final objective of the present work is the accurate prediction of the dynamic stiffness behaviour of complex rubber parts using finite element simulation tools. For this purpose, it becomes necessary to perform a complex rubber compound material characterisation and modelling work; this needs …
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Characterisation of network structure in recycled rubber
Produced by existing size reduction technologies, rubber crumb is the most valuable type of recycled material. However, only a limited amount of untreated crumb can be used in new tyres due to significant property loss. The de-vulcanisation process offers the potential for providing high quality …
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Coagulant dipping of natural rubber latex
A detailed study has been made of' the coagulant dipping of natural rubber latex using calcium, chloride as the coagulant. The primary object of the investigation was to deepen understanding of the kinetics and the mechanisms of deposition. Results are given for the effect of variables such as …
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Further investigations of the prevulcanization of natural rubber latex
A comparison has been made of the vulcanization of NR in the latex form and in the dry form. In latex form, NR was found to vulcanize at a much faster rate than in the dry form. The faster rate of reaction in latex prevulcanizatIon is attributed to the presence of the aqueous phase which acts as a …
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Set behaviour of epichlorohydrin elastomers
Traditionally Epichlorohydrin (ECO) elastomers are cured by thiourea (ETU)-Lead (PbO) curing systems. However, owing to the current concerns regarding health, safety and the environment such systems are now classified as relatively high risk systems. ECO elastomers are widely used as seals and …
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Tear strength of filled rubbers
The strength of black-filled rubbers has been investigated under a variety of test conditions using various compounding formulations, of both strain-crystallizing and non-strain-crystallizing elastomers. The enhancement in the tear strength is substantial when knotty tearing occurs. In knotty …
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Peroxide prevulcanization of natural rubber latex
The peroxide prevulcanization of NR latex using a range of commercially-available organic peroxides and an inorganic peroxide (potassium peroxydisulphate), in both activated and non-activated systems, has been investigated. A range of reducing agents and compounds that are known to promote …
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Modification of natural rubber by graft copolymerisation of non-ionogenic hydrophilic monomers in latex
This work is an investigation of the modification of natural rubber (NR) by graft copolymerisation of hydroxyethyl acrylate (HEA), hydroxypropyl acrylate (HPA), hydroxyethyl methacrylate (HEMA) and hydroxypropyl methacrylate (HPMA) in NR latex. Initial studies showed that, at low monomer …
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Modification of the mechanical properties of synethetic hydrogels by various techniques
A study in the field of hydrogel reinforcement has been carried out, the reinforced hydrogel being a copolymer of 2-hydroxyethyl methacrylate and methacrylic acid, crosslinked with ethylene glycol dimethacrylate and having an equilibrium water content at pH 8.5 of 74% by weight. Three methods of …
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Effects of water-soluble polymers upon some properties of natural rubber latex
An investigation of the effects of various water-soluble polymers upon some properties of natural rubber latex has been carried out. All the polymers, which were of two principal types, distinguished according to the rate of addition of polymerisation reactants, were prepared by free-radical …
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The formation of brittle phases in brazed zirconium joints
The purpose of the study was to investigate the metallurgical interactions that occur during the brazing of zirconium with Ag-28Cu filler, with particular reference to their effect on mechanical properties. The ultimate aim was to provide information that would aid in the production of tougher …
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Synthesis and performance of novel azo initiators with special reference to emulsion polymerisation
Derivatives of 4,4'-azobis-4-cyanopentanoic acid were prepared using its diacid chloride and various hydroxyl and amino compounds. The objective was to obtain substances that would act both as initiators for different modes of free-radical polymerisation and also as stabilisers for emulsion …
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An investigation into the polyethylene extrudates produced by simultaneous orientation and high temperature quenching
An apparatus was designed and constructed to allow a molten polymer extrudate under tension - or draw-down - to pass through a volume of liquid metal alloy in order that the extrudate would rapidly reach the temperature of the metal and be fully quenched on leaving the medium. The temperature of …
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Processing behaviour of NR latex with special reference to dipping
A detailed study of the effect of added ingredients upon processing behaviour of NR latex with reference to dipping has been conducted in an endeavour to further understanding of the fundamental science underlying latex dipping processes.
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Interaction of phenol-formaldehyde condensates with isoprene rubber
The study is concerned with the interaction between p-tertiary butyl phenol-formaldehyde condensates and isoprene rubber under conditions resembling those used in industrial vulcanization processes, and involves investigations of reaction rates, mechanisms of reactions and structures produced. The …
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Synergic control in MIG welding and penetration control in TIG welding
Part 1: Synergic control in MIG welding. Synergic controls (i.e. real time control methods) for both steady DC open arc and short circuiting arc operations have been developed in this study. These have been based on the generalised quadratic and linear ‘power-current' and linear ‘voltage-current’ …
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The colouring, sealing and abrasion resistance of anodic oxide coatings
The service performance of anodised aluminium in architecture is dependent upon the control of the anodising, colouring and sealing processes. The quality of the anodic oxide film is determined by assessment tests. The use of a nitric acid ‘predip’ on soft films was shown to dissolve a soft …
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Mechanical reinforcement of films from rubber latices by added polymer particles
Various factors and filler characteristics which influence the ability of added polymer particles prepared as latices by emulsion polymerisation to reinforce the mechanical properties of films derived from rubber latices, particularly post-vulcanised natural rubber latex, have been investigated. …
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An investigation into the relationship between processing, orientation and properties of low density polyethylene films
The effect of changing processing conditions on the mechanical properties of LDPE, LLDPE and blends of LDPE and LLDPE blown films was studied.The results were analysed by relating the change in mechanical properties with the change in the residual strain of manufactured film. The residual strain …
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Energy changes on deformation of a pneumatic tyre
The major part of this work is concerned with the development of the apparatus and the techniques involved in the measurements of the load-deflection characteristics of a pneumatic tyre and its associated changes in the pressure and volume of the air contained in it. A satisfactory results were …
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