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The paper's purpose is to optimise lab‐size synthesis process of a fluorene‐containing epoxy resin, characterise structure of the resulting epoxy resin and evaluate mechanical properties of the cured fluorene‐containing polymers.

The synthesis of the fluorene‐containing epoxy resin was accomplished by the polycondensation of 9,9‐bis(4‐hydroxyphenyl)‐fluorene and epichlorohydrin in the presence of quaternary ammonium salt and composite solvent under vacuum. The chemical structure of epoxy resin thus obtained was characterised with FTIR, NMR and MS. The shear strengthes of cured fluorene‐containing epoxy resin were determined and compared with that of cured E‐44 bisphenol A epoxy resin and F‐44 novolac epoxy.

The epoxide equivalent weight (EEW) of the fluorene‐containing epoxy resin reached 240‐246 g/mol under optimal epoxidising condition. The resulting epoxy resin exhibited approximate high temperature performance relative to F‐44 novolac epoxy, much better heat resistance than that of E‐44 epoxy resin and lower moisture uptake than that of the two above‐described resins.

The shear strength of cured fluorene‐containing epoxy resin was relatively low at ambient temperature, whereas was much higher than that of bisphenol A epoxy resin at higher temperature, making it a potential candidate for many applications such as high temperature adhesives, coatings and matrix resins for advanced composite.

The method for preparation was modified and improved, structure characterisation was comprehensive. The material prepared could find numerous applications as heat‐resistant adhesives and matrix resins.

The X‐ray diffraction patterns of epoxy resins: four samples with different epoxide equivalents and coal‐tar blended epoxy resins: three samples with different epoxide equivalents were recorded using CuKa X‐ray radiation. These X‐ray diffraction patterns were indicating the amorphous nature of the resins. Their intensity curves were subjected to Fourier Analysis for the first time in order to get more information about the difference between epoxy and coal‐tar blended epoxy resins in terms of their internal structure such as particle size, percentage crystallanity and electron density fluctuations. Also, the effect of different epoxide equivalent on these physical parameters was interpreted successfully in epoxy as well as coal‐tar blended epoxy resins.

The paper presents the results of measuring the diffusion processes in epoxy resins based on bisphenol A and bisphenol S hardened with aromatic polyamines. The effects acting on the diffusion of acids into the resins thus hardened are discussed. These involve mostly the diffusion processes of solutions connected with a chemical reaction affecting the chemical stability of material. The chemical resistance of epoxy resins is affected by the molecular weight and type of epoxy resin, the polyamine functionality, the polyamine concentration, and the kind of plasticizer. The measurements performed by a microscopic method gave the values of diffusion coefficients relating to the penetration of some inorganic and organic acids into the epoxy resin based copolymers.

To reduce the cost of epoxy adhesive without affecting the properties of epoxy adhesive in two pack system.

For effective toughening, adhesion, chemical resistance, etc. various compositions were made by incorporating flow modified solid epoxy resin. The impact, adhesive strengths and some other properties of the unmodified and modified epoxy networks were characterised.

The modification of epoxy resin using flow modified solid epoxy resin showed significant enhancement of impact and adhesive strengths and chemical resistance over the unmodified one. The optimum results were obtained at 13.66 parts per hundred parts of epoxy resin (phr) of modifier by replacing 4.33 phr of aerosil.

The modifier, 7004 FM, used in the present context was high molecular weight flow modified epoxy resin. Besides, these results could be obtained from other grades of flow modified high molecular weight epoxy resin. In addition, the efficiency of modification of epoxy resin using this could also be studied.

The method developed provided a simple and practical solution to removing the costly aerosil without affecting properties such as toughness, adhesive strength and chemical resistance of the cured epoxy.

The method for enhancing toughness, adhesive strength and chemical resistance of cured epoxy was novel and could find numerous applications in surface coating and adhesive.

The purpose of this paper is to report the preparation, characterisation and machinability of resin hybrid GFRP composites, which are made of glass fibre and the mixture of epoxy & polyester resin.

Resin hybrid GFRP laminates containing 0, 20 and 40wt% of polyester resin with the epoxy resin are prepared by conventional hand layup technique using glass fibre as the reinforcement. The variation of break load and shear strength for three different combinations of epoxy and polyester resin are studied by ASTM. A plan of experiment based on Taguchi was established with prefixed cutting parameters and the machining was performed. A stylus type profilometer to examine the surface roughness and shop microscope to examine the delamination of resin hybrid GFRP laminates were used. An analysis of variance (ANOVA) was performed to investigate the cutting characteristics of resin hybrid GFRP composite materials using solid carbide end mill. The correlation was obtained by multiple‐variable linear regression using Minitab 14 software.

Taguchi analysis reveals that the resin hybrid GFRP laminate provides better machinability in terms of surface roughness and delamination when compared to homogenous GFRP laminates (pure epoxy resin). Polyester resin enhances the machinability of the GFRP laminates.

The machinability of the resin hybrid GFRP laminates can be improved further by modifying the polyester resin percentage.

The resin hybrid GFRP laminates so developed can be used in aircraft and aerospace applications to increase the shear and work of fracture properties.

HIGH SOLIDS COATINGS Review Articles Without question, the major motivation for high solids coatings is government regulations. An interesting article which summarises what the coatings industry has done in order to meet air pollution regulations in the United States has been provided by Burger (Metal Finishing, July, 1982, p. 59). His list includes, in addition to high build and solventless coatings, electrodeposition, electrostatic powder coatings, Rule 66—acceptable solvent‐based coatings, and water‐borne coatings. Air pollution results not only from solvents but from the particulates released during surface preparation. Pollution due to surface preparation has been alleviated by the use of white water sandblasting, centrifugal and rotary blast cleaning blast cleaning with carbon dioxide pellets, improved ventilation air filters and safety equipment, plasma arc and laser cleaning, sonic cleaning, special chemical cleaning, and surface preparation and vacuum blasting. In addition, solvent recovery units have been utilised extensively in industrial coatings.

Epoxy resins are compounds which contain in their molecule more than one 1,2 epoxy group capable of undergoing polyreactions, referred to as curing reactions. The presence of epoxy groups may be either internal, terminal or on cyclic structures. Polyreactions take place at varying temperatures from low room temperature cure to high temperature cure systems upon addition of curing agents such as amines, amides or carboxylic acid anhydrides. The uncured resins which range from low viscosity liquids to high melting solids, soluble in organic solvents, become insoluble, infusible hard materials on curing due to crosslinked structure of the cured products.

Developments in the area of epoxy resins make rich contributions to the patent literature. The single subject on which more patents are issued than any other is curing agents. Accordingly, this section will describe some of the patents on epoxy resin curing agents that have been issued in the past few years. Associated with the curing agents are catalysts, coreactants, and modifiers.

The epoxy resins need to be added with flame retardant to ensure safety in practical applications. There were a lot of highly toxic substances in the flame retardant used in the past, which caused greater harm to human body and the environment. Therefore, this study aims to propose a research on the synthesis of new phosphorous-containing flame retardant and the properties of flame retardant epoxy resins.

The flame retardant intermediate DOPO was synthesized using o-phenylphenol as the substrate. The intermediate was mixed with D4Vi under certain conditions to synthesize a new phosphorous-containing flame retardant. The flame retardant was added to the epoxy resins to prepare the flame retardant epoxy resins.

The experimental results show that the synthetic new phosphorous-containing flame retardant is far less harmful than the flame retardant used in the past and has extremely low toxicity, which is suitable for use in practical projects.

The new phosphorus-containing flame retardant synthesized by forms a more uniform and dense carbon layer in the combustion process, which well protects the underlying materials, thus improving the flame retardancy of epoxy resin materials. The harm of the new phosphorus-containing flame retardant is far less than that of ordinary flame retardant. The flame retardant used in the past has very low toxicity and is suitable for practical engineering.

Epoxy resins have probably provided more interesting chemistry than any other polymer the paint industry uses. In this category of interesting chemistry is Russian work [World Surface Coatings Abstracts (1978) Abstract No. 1558] which describes the preparation of structurally coloured epoxy resins — i.e. of epoxy resins which are inherently coloured. The work involves condensing bisphenol A and epichlorohydrin in the presence of small amounts (0.1 to 0.5 weight per cent) of a coloured co‐monomer dye. The dye, for example, can be the glycidyl ether of alpha aminoanthroquinone. Coloured products resulted which presumably would provide coatings with intrinsic colour. Of course, this colour could be modified by extrinsic dyes and pigments. The concept of producing coloured polymers is not a new one. One approach to making black polyethylene for black film is to carry out the polymerisation of the ethylene in a fluid bed of carbon particles. The carbon particles presumably serve as a nucleus around which the polymer forms and at the same time serves to impart a black colour to the polymer particle. This technology has never been commercialised but it is certainly of interest to the paint chemist for it presents a new concept in carrying out a major objective of the paint industry — namely, to impart colour to solutions of polymers.