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Different methods have been carried out to prepare barium metaborate pigments and to find out the suitable method of preparation taking into account ease of industrial application and the yield of the product. The properties of the prepared pigments were tested and compared with those of the commercial pigment. The solubility of the prepared pigment was found to be high and needed to be decreased. Many different methods of treatment were used and six grades of barium metaborate pigment were obtained. It was found that the addition of silicate to the prepared pigments has decreased their solubilities.

Reports on tests in which barium metaborate pigment and its modified form are prepared, identified by chemical and X‐ray diffraction methods, and specified according to standard methods. Evaluates the modified barium metaborate as a new filler for paper making by carrying out two series of experiments. Details the results which showed that the efficiency of the filler retention when using modified barium metaborate was higher than that of the other two conventional fillers. Reveals that at relatively low filler addition (2–5 percentage weight), higher improvement in the strength properties can be obtained when using the modified pigment instead of titanium dioxide and kaolin, but observes the reverse (i.e. a detrimental effect) at relatively high filler addition (8–10 percentage weight). Discovers that the optical properties of the modified pigment‐loaded sheets lie between those of titanium dioxide and kaolin. Shows that blending barium metaborate with kaolin or titanium dioxide has a significant effect on strength properties rather than optical properties. Concludes that modified barium metaborate pigment can be successfully used in paper filling applications and that modified barium metaborate pigment‐kaolin blend (80/20 per cent) can be used instead of titanium dioxide as a paper filler.

Barium metaborate as a new less toxic anti‐corrosive pigment was tested for protection against corrosion in an atmospheric exposure testing station set in Egypt on Alexandria seashore. Seventy paints were prepared, based on six grades of laboratory prepared barium metaborate pigments. The paints could be classified into three groups according to the type of the binder; each group comprises seven subgroups according to the pigment grade used. The paints were tested first in the laboratory and then in actual environment. Commercial barium metaborate (Busan 11‐M1) based paints were prepared and used as a blank. High corrosion protection properties are obtained for up to nine years exposure. Results showed that mixing barium metaborate pigments with neutral binder gave better results than mixing them with acidic binder. Laboratory prepared pigments gave better results than the commercial one. It was also found that corrosion protection of these pigments increases with the increase of pigment modification.

Summary The present work aims to study the inhibition mechanism of barium metaborate pigments. Six grades of barium metaborate pigments were prepared in the Laboratory of Polymers and Pigments, National Research Centre of Cairo, Egypt. The methods of preparation modification and evaluation is the main subject of a recent article. The pigments were incorporated, with other ingredients, into formulations, and the electrode potential, electrical resistance, water uptake and weight loss measurements were taken. Formulations based on a commercial pigment supplied by an international company were prepared and used as blanks.

Flash rusting and corrosion undercutting of water‐thinned paint films on iron surfaces are caused by the electrochemical decomposition of that steel surface. Flash rusting is that rust‐coloured spotting which occurs as the iron is solubilized and bleeds through that water‐thinned paint film. The steel simply corrodes because of the flow of electric currents that occur as the pure iron reverts to its more stable compounds: ferric hydroxide, hydrated ferric oxides and ferric oxides. This paper reviews the chemistry of flash rusting and corrosion undercutting and reports on the successful applications of modified barium metaborate in providing both initial and long‐term corrosion resistance for water‐thinned paints on steel. Several physical factors that contribute to flash rusting and corrosion undercutting are also discussed.

Seventy paints were prepared, based on six grades of laboratory prepared barium metaborate pigments. The paints could be classified into three groups according to the type of the binder; each group comprises seven sub‐groups. The paints were tested first in the laboratory and then in actual environment (above and under sea water). Commercial barium metaborate (Busan 11‐M1) based‐paints were prepared and used as a blank.

MODERN heavy‐duty motor oils are almost invariably formulated with detergent‐dispersant type of additives. The types of additive normally employed for this purpose are organo‐metallic detergent‐dispersants such as metal salts (barium/calcium) of alkyl phenols, petroleum and synthetic sulphonic acids, condensation products of olefins and P2S5, alkyl salicylic acids, etc., on the one hand, and the polymeric ashless types of dispersants such as polymethacrylic esters and N‐substituted long chain alkyl succinimides, on the other. Barium and calcium salts of the petroleum sulphonic acids, however, are by far the most widely used dispersant‐detergent additives. These additives are manufactured from the sodium salts or the sulphonic acids obtained as a by‐product during the sulphonation of mineral oils for the manufacture of white oils and transformer oils. The average molecular weight of the sodium salts is in the range 450—500.

This paper aims to investigate and prepare the composite polyurea greases with excellent thermal stability and tribological properties.

In this paper, composite Ba-based (Ba, barium) tetra-polyurea lubricating greases were prepared with two different methods: mixing Ba-based gelatinizer and tetra-polyurea gelatinizer by a physical method; and introducing barium carboxylate into tetra-polyurea molecules by a chemical method. The properties of the products, such as heat stability, water resistance and friction performance, were analyzed with thermogravimetry, water-resistance test and four-ball friction test.

The results indicated that the products obtained by chemically introducing barium carboxylate into tetra-urea molecules showed better elevated temperature tribological properties, and the disadvantages of the polyurea greases with high temperature hardening were also obviously improved. The cone penetration rate at 180°C for 24 h is only 3 per cent. The friction coefficient can be decreased to 0.44 and the last non-seizure load value was increased from 560 N to 1,120 N without any other additives.

The research is significant because the prepared composite grease showed excellent performances, such as the outstanding thermal stability, water resistance and excellent extreme pressure and anti-wear properties, which may be widely applied in steel, metallurgy, bearings and other industrial fields.

Although blanc fixe and lithopone have become less important as pigments these days, current resources of British barytes still prove of interest to several industries. In Scotland the Highland and Islands Development Board is developing the search for barytes, especialy since a major application has come in winning North Sea oil and gas. Barytes admixed with colloidal clay is essential as “heavy mud lubricant,” with an estimated 95 per cent of world resources of barytes now consumed in this major field. Every hundred feet depth of drilling calls for one tonne of ground barytes — all of this being returned to the earth and lost. With barium called for in pigments and extenders for the paint, rubber and chemical industries, British resources of barium minerals assume much significance.

Modified barium metaborate (BMB) was originally developed and patented as a mould inhibitor for oleoresinous systems. It was noted from exposures on our test fence that the product exhibited definite corrosion inhibiting properties. Through this observation further studies were initiated and it was determined that BMB was an excellent corrosion inhibitor in both latex and oleoresinous systems. Its effectiveness as a corrosion inhibitor is usually attributed to (1) its alkalinity which neutralizes the acidity of weathered paint films and which may reduce the reactivity of metal substrates, and (2) the metaborate ion which passivates the anode in essentially the same manner as the chromate ion.