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To improve the efficiency of flame retardant paints for wood by using different fillers and thermoplastic and thermosetting binders.

For effective flame retardancy, various paint compositions were made by incorporating different binders and fillers. The physical and mechanical properties, of the paint films, storage stability, limited oxygen index (LOI) and differential thermal analysis were investigated.

Diammonium hydrogen orthophosphate has all the characteristics required to be used as flame retardant filler for paint, in contrary to magnesium hydroxide, Mg(OH)₂, which has undesired effect on the storage stability of paints based on alkyd resin. The values of LOI depend on the type and composition of the binder.

The flame retardancy of the prepared paints could also be evaluated using more conventional methods such as oxygen index test.

Special fillers and binders that could be used in highly efficient flame retardant paint for wood have been identified.

The fillers are non‐toxic. Different fillers obtained could be used in various thermosetting binders beside thermoplastic ones.

Magnesium ferrite pigments were evaluated as active pigments in anticorrosive water‐borne paints. The study includes the use of two different anticorrosive pigment volume concentration (APVC), 15 and 25 per cent and fixed the Q value (the pigment volume concentration/critical pigment volume concentration ratio) in both paint formulations. Epoxy and acrylated alkyd resins were used as binders. The paints were evaluated by accelerated salt spray tests, corrosion tests in condensed water and sulphur dioxide chambers and electrochemical evaluations. The results obtained were compared with reference paints containing zinc ferrite and zinc phosphate pigments. Ferrite pigments passivate the carbon steel directly in the case of neutral epoxy resin binder or indirectly due to the soaps produced as a result of reaction with the acidic acrylated alkyd resin binder. A lower per cent, i.e. 15 per cent of APVC was found to be sufficient to provide satisfactory anticorrosion protection.

Fire retardant alkyd resins modified with dehydrated caster oil were prepared directly without going though the alcoholysis step. The method is based upon dehydrating castor oil with trimellitic anhydride. The oil thus produced contains sufficient combined carboxyl groups capable of polyesterifications with triols and glycerol or chlorinated monocyclic acetal and glycerol, and the macro‐structure is completed by further reaction with PA or chlorendic anhydride to obtain flame retardant resins. Melamine formaldhyde resin have been used in combination with the previous alkyd resins to improve hardness and also fire retardancy.

Fire retardant oil‐modified alkyd resin based on chlorendic ahnydride (1,4,5,6,7 7‐hexachlorobicyclo‐(2,2,1) hept‐5‐ene‐2,3‐dicarboxylic anhydride) have been synthesized using linseed oil, phthalic anhydride and glycerol. Several paint formulations were designed to study the effect of pigment/binder ratio, antimony trioxide and chlorinated thermosetting and thermoplastic polymers on fire retardancy. Oxygen index method was used to evaluate the fire retardancy of paints. The chlorinated alkyd resin was used as a plasticizer for laroflex MP 35 to improve the fire retardancy of the thermoplastic chlorinated polymer.

A petroleum fraction having a boiling range 200–250°C (kerosene), free from aromatic and n‐paraffin hydrocarbons was oxidised by bubbling air at 130–150°C, at normal pressure, in the presence of cobalt naphthenate as a catalyst. Optimum yield of oxynaphthenic acid was obtained after sixteen hours and thirty minutes oxidation at 140°C. Two layers were formed, the bottom product was a viscous liquid insoluble in petroleum ether and alcohols. Oxyacids, mainly hydroxy naphthenic acids, were obtained after treatment and purification of the viscous liquid.

To prepare of fine particle size magnesium ferrite pigments by sol‐gel method.

Different magnesium ferrite pigments with stoichiometric ratios were prepared by sol‐gel and dispersion methods. The characterisation of magnesium ferrite pigments were based on X‐ray diffraction, transmission electron microscope, particle size distribution, thermal and magnetometric analyses.

The type of polymer and the starting inorganic materials (oxides or salts) have a significant effect on the properties of the magnesium ferrite pigments prepared.

The magnesium ferrite pigments, prepared and used in the work reported here were synthesised from magnesium and iron oxides, oxalates and chlorides. Urea formaldehyde resin and acrylic polymer were used as the dispersing media. Various other materials, e.g. carboxymethyl cellulose, ethoxy methyl cellulose, polyvinylalcohol and 2‐hydroxyethyl methacrylate and polyacrylamide can also be used to achieve similar effect.

The sol‐gel method provided a fine particle size and different particle shapes. Therefore, the method of preparation could be used to produce fibres, films and monoliths.

The magnesium ferrite pigments prepared could be use in numerous paints for steel protection.

The purpose of this paper is to search for toxic anticorrosive pigments’ substitute in protective coatings is one of the important tasks that the specialists in the field of steel corrosion face.

One of the ways to solve the problem of metal corrosion is to use complex oxides as pigments, which are characterized as low-toxic compounds and possess the ability to inhibit corrosion.

In the production of ferrites, it is possible to use production waste as raw material, and that makes it possible to reduce the price of the resulting product and solve environmental problems simultaneously.

Permanent growth of world production is accompanied by the increasing environment corrosiveness, associated with the intensification of air, water basin and soil pollution by industrial waste. This, as well as the continuously increasing operated metal stock, has recently made the tendency of metals’ total loss from corrosion steadily increasing. All of this points to the importance of studying corrosion processes and the systematic and effective fight against metal corrosion.

A dewaxed and dearomatized petroleum fraction having a boiling range 180–250°C was oxidised by air at 140°C. under atmospheric pressure using cobalt or manganese naphthenate as catalyst. The oxynaphthenic acids were isolated from the oxidation product, purified and then neutralised to sodium salts.

Following the reorganisation of Diamond Shamrock's UK operation, Diamond Shamrock Process Chemicals Ltd, Leeds, has appointed Mr. Richard J. Fletcher as sales manager. Prior to taking up this appointment, Mr. Fletcher was commercial manager of Duolite International Ltd, the ion exchange company owned by the Diamond Shamrock Corporation.

To synthesise anticorrosion pigments of a lamellar and core‐shell type based on Zn, Ca and Mg ferrites for metal protecting paints.

The anticorrosion pigments were synthesised from oxides or carbonates at high temperature. The pigments synthesised had particles with a pronounced lamellar‐tubular shape consisting of MgFe₂O₄; Mg_0.8Zn_0.2Fe₂O₄; Mg_0.6Zn_0.4Fe₂O₄; Mg_0.4Zn_0.6Fe₂O₄; Mg_0.2Zn_0.8Fe₂O₄; ZnFe₂O₄; Ca_0.2Zn_0.8Fe₂O₄; and CaFe₂O₄. The other type of synthesised ferrite pigments were core‐shell anticorrosion pigments where a layer corresponding to the compositions including MgFe₂O₄/KAl₃Si₃O₁₁; Mg_0.8Zn_0.2Fe₂O₄/KAl₃Si₃O₁₁; Mg_0.6Zn_0.4Fe₂O₄/KAl₃Si₃O₁₁; Mg_0.4Zn_0.6Fe₂O₄/KAl₃Si₃O₁₁; Mg_0.2Zn_0.8Fe₂O₄/KAl₃Si₃O₁₁; ZnFe₂O₄/KAl₃Si₃O₁₁; Ca_0.2Zn_0.8Fe₂O₄/KAl₃Si₃O₁₁; and CaFe₂O₄/KAl₃Si₃O₁₁ was applied onto the core – white mica – by a chemical reaction. The pigments prepared were characterised by means of X‐ray diffraction analysis, particle size distribution measurement, and scanning electron microscopy. The anticorrosion pigments synthesised were used to formulate alkyd paints that were tested in corrosion atmospheres.

Lamellar particles were detected in the pigments prepared, whereas quality coverage of the core was identified in the core‐shell ferrites. Good anticorrosion efficiency was detected in all of the pigments synthesised.

The pigments synthesised can be conveniently utilised in paints to protect metal bases from corrosion.

The method of using the ferrites synthesised as metal protecting anticorrosion paints is new. Of great benefit are the application and the method of synthesising the anticorrosion pigments that do not contain any heavy metals and are environmentally friendly.