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Explores the possibility of preparing elastic and hard ebonite coatings, utilizing the properties of oligobutadienes without ending functional groups. Examines the vulcanization processes leading to formation of rubberizing ebonite coatings on samples of oligobutadienes. Finds that the most effective bonding material for non‐solution compositions is ebonite coatings.

The purpose of this paper is to research a multi-zone rubber vulcanization process heated by induction.

The design is an abstract setup model with two zones, where the homogene rubber compound is heated with different regimes. Simulation is completely done in ANSYS Mechanical by the finite element method solution. The research is made mostly simulative.

The results show that it is possible to obtain a factor-three vulcanization level difference in a core of a 20-mm rubber plate in a distance of less than 60 mm, while the heating is done from the side of the surface.

The originality is the combination of rubber vulcanization with a dynamic heat source in a form of electromagnetic induction applied on the mold form. This allows a high level of control of the vulcanization process of the rubber compound.

Polyoxyethylated hydroxy benzyl oleamide has found use in lubricants to prevent adhesion in moulds during the production of vulcanizates of natural and of synthetic rubbers. Polyoxyethylated oleamide acts as a mould lubricant for synthetic rubbers, whilst polyglycol 400 dilaurate can be used to reduce the time and temperature necessary for the recovery of old vulcanizates using paraffin oil and bitumen. Anti‐fogging properties can be sustained in rubber hydrochloride films by the use of polyglycol 1500 dilaurate, and improved percentage elongation can be promoted in intimate blends of polystyrene and SBR rubbers by the inclusion of polyglycol 4000 monostearate. Polyoxyethylated sorbitan monostearate acts as an emulsifer in the emulsion polymerisation of styrene, butadiene and styrene/ butadiene copolymer rubbers, and it can perform as an anti‐static for the latter. Polyoxyethylated stearylamine can be incorporated into lubricants designed to prevent adhesion in moulds during production of vulcanizates of synthetic and of natural rubber, and rubber latexes and other aqueous dispersions of rubber can be rendered more stable by the employment of polyoxyethylated stearyl alcohol, and thus allow storage in untreated containers for long periods of time. Polyoxypropylated sorbitan monopalmitate will serve as a parting agent, releasing aid, for unvulcanized rubber and vulcanized rubber, without interfering with further bonding and coating of rubber.

A number of derivatives of vegetable and animal oils and fats are useable in the processing of rubbers, including fatty acids, fatty acid amides, amines, metallic soaps, and sulphur containing materials, etc.

The purpose of this paper is to develop a novel organic‐inorganic (epoxy‐silicone) hybrid resin for application in heat resistant surface coatings.

Thermally stable aminosilicone resin was prepared by using diethoxydimethyl silane and γ‐aminopropyldiethoxy methyl silane.

The hybrid epoxy silicone resin shows significant properties such as toughness, chemical resistance and thermal stability.

The prepared amino siloxane was cured by commercially available epoxy resin PG 100 and toluene diisocyanate in different ratios at high as well as at room temperature to develop high‐temperature vulcanisation and room temperature vulcanisation resin systems.

The hybrid epoxy silicone resin may be used as heat resistant coatings due to their low shrinkage and lesser internal stress.

The developed hybrid epoxy silicone resin was novel for application in thermally stable coatings.

Last month, in Part 1 of this article, various elastomeric materials were described for use as anti‐corrosive linings for plant and equipment. Methods of application vary, of course, according to circumstances. In this second part, consideration is given to application methods and design problems

Describes how, with plasma cleansing, metal and plastic components can be prepared thoroughly, to the highest standards, for paint application and other surface treatment, vulcanization or bonding. Where components are first pre‐cleaned, using water or a cold cleansing agent, then subjected to plasma treatment, there are major dividends to be earned in environmental terms, but this process can also bring about quite startling improvements in the quality of the end product.

THE term synthetic rubber is strictly related only to a product which is physically and chemically indistinguishable from natural rubber; no material has been developed fitting such a definition and synthetic substances which possess properties approximating to those of the natural product are generally regarded as synthetic rubbers. More exact definition has been attempted by many authors in particular to so‐regard only those products which are capable of vulcanization, thus turning from plastic to clastic bodies. No new word describing the synthetic bodies has been accepted and it will now prove difficult to divorce the term “synthetic rubber” from any material showing reasonably comparable properties with natural rubber.

Rubber gaskets find wide applications in steel structures. Gaskets are usually used on the edges or on the nail hole positions. These are the weakest positions, where corrosion starts, whether the structure is protected by paint or by other methods. In this work, anticorrosive pigments were incorporated in rubber formulations. They are tested by corrosion protection when used as gaskets with steel panels. Results showed that the presence of anticorrosive pigments in rubber gaskets prevents early rusting under it in comparison with the blank. Zinc‐tetroxy chromate pigment exhibited the highest rust inhibiting power when chloroprene rubber formulations were used. The change of the pigment percent barely affect the quality of protection when syrenebutadiene rubber formulation were used. Zinc tetroxy chromate pigment improved the physico‐mechanical properties of chloroprene rubber under investigation. The used formulations can tolerate thermal oxidative aging at 90°C up to 8 days. The rate of vulcanization was not affected by increasing the concentration of the inhibitive pitments.

A new method for modifying the properties of aluminium oxide had been developed which allowed alumina to be used as a white, reinforcing filler in various rubber composites to replace carbon black, producing high performance white rubber vulcanizates comparable to those loaded with carbon black that could be coloured if needed.

Alumina was treated with small amounts of ammonium molybdate. Characterisation of modified aluminium oxide was carried out using transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Also, evaluation of the pigments prepared, in terms of oil absorption, specific gravity, and bulking value using international standard testing methods was performed. The morphology of the natural rubber composites loaded with the new modified alumina were studied using SEM. Kraus equation was used to analyse the extent of polymer‐pigment interaction, while Mooney‐Rivlin relation was employed to study the near equilibrium stress‐strain behaviour.

The results showed that, the pigment had a significant effect on the rheological characteristics (scorch, cure time, etc.), mechanical properties, stress and strain at yield and at rupture of white rubber vulcanizates prepared resulting in high performance.

As concentration of molybdenum oxide increased in the alumina crystals, the reinforcing effect in rubber composites also increased till an optimum concentration where such a reinforcing effect reversed. However, investigation of the application of these pigments in other systems such as an anticorrosive pigment in paint formulations and reinforcing filler in polyester composites could also be interesting.

The pigments prepared could be used as reinforcing filler in plastic composites and also as anticorrosive pigment in paint formulations.

Aluminium oxide is a cheap compound. The originality of the work lay in the finding that by adding trace amounts of molybdenym to it, aluminium oxide's properties changed dramatically resulting in more effective action in reinforcing rubber composites filled with such modified alumina, producing white rubber composites with comparable properties to those loaded with carbon black, and may exceed them in some cases. This allowed the preparation of coloured rubber with good rheological and physical properties.