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It would be easy to make the general statement that the only major factor an engineer need consider when selecting a pipe‐protection material is that it should resist corrosion. Certainly he must be concerned with electrolytic and galvanic attack, abrasion, chemical action and the effect of weather. This, however, is only part of the story. This article reviews the properties of polyvinyl chloride tapes and the very real part which they, and, in particular Scotchrap PVC tapes, are playing in the prevention of pipeline deterioration.

Adhesion promoters: Some oleochemicals can promote the adhesion of polymers to various surfaces, e.g. stearic acid can increase the adhesion of polyolef ins to metals and to the surfaces of other polymers. Erucamide is effective in the lamination of cellophane to polyethylene films, and alumina‐modified iron stearate has been found effective in aiding the adhesion of polyethylene to steel surfaces. The effect of oleamide on the adhesion of polyethylene to aluminium and to nylon 6 has been studied. Stearic acid had an adhesion promoting role in polyethylene/aluminium laminated packaging film. Barium stearate can effect the adhesiveness of poly(vinyl chloride).

POLYMERS are mixtures of compounds of similar chemical composition and of high molecular weights. Naturally occurring products such as rubber, cellulose, proteins and shellac, extracted materials such as asphaltic bitumens, and synthetic products, produced by a polymerisation process, are all included under this heading.

Of the thermoplastics group of materials, unplasticised polyvinyl chloride, commonly known as rigid PVC, appears to have made the slowest progress in the U.K. It was introduced here shortly after the war, but, as recently as 1958, the annual usage for industrial pipes was estimated at only 500 tons. In the same year, France, Holland and Italy processed approximately 4,000, 8,000 and 12,000 tons respectively. This article indicates the scope of the material in corrosive environments.

The formulation of industrial finishes to protect and improve the appearance of mass‐produced articles has become an increasingly complicated technique with the growing range of materials flow available. In this article Mr. Macrae, after discussing surface preparation and application methods, describes the formulation and performances of stoving enamels, cold‐curing finishes and air‐drying finishes. He concludes that even with the number of resins available today there is still much room for improvement.

PAINTS as methods of passive corrosion protection must be considered essential for steel and metal structures, and are as old as the need to preserve their value. Moreover, the attempt has long been made, not only to cover the surfaces of steels with organic paints, but also to protect them actively and thereby to exclude the danger of under‐rusting as a result of crack and pore formation or absorption of water in the organic paint films. Such active corrosion protection is already about 200 years old. But the development, the manufacturing technique, and not least the price, often make it impossible to provide surfaces with a coating by hot‐dip or spray galvanizing.

Much to the relief of everyone, the general election has come and gone and with it the boring television drivel; the result a foregone conclusion. The Labour/Trade Union movement with a severe beating, the worst for half a century, a disaster they have certainly been asking for. Taking a line from the backwoods wisdom of Abraham Lincoln — “You can't fool all the people all the time!” Now, all that most people desire is not to live easy — life is never that and by the nature of things, it cannot be — but to have a reasonably settled, peaceful existence, to work out what they would consider to be their destiny; to be spared the attentions of the planners, the plotters, provocateurs, down to the wilful spoilers and wreckers. They have a right to expect Government protection. We cannot help recalling the memory of a brilliant Saturday, but one of the darkest days of the War, when the earth beneath our feet trembled at the destructive might of fleets of massive bombers overhead, the small silvery Messerschmits weaving above them. Believing all to be lost, we heaped curses on successive Governments which had wrangled over rearmament, especially the “Butter before Guns” brigade, who at the word conscription almost had apoplexy, and left its people exposed to destruction. Now, as then, the question is “Have they learned anything?” With all the countless millions Government costs, its people have the right to claim something for their money, not the least of which is the right to industrial and domestic peace.

The 679 represents the latest in the ever increasing number of “special analytical instruments” from METROHM. The 679 now not only offers the possibility for the determination of the oxidative stability of oils and related products, but also permits the testing of the thermal stability of plastics.

IN recent years there has been a marked development in the use of various types of rigid vinyl sheet for the construction of certain parts of plant which are normally exposed to corrosion in various forms. This applies particularly to chemical plant and the two main fields are the lining of tanks in the pickling and plating departments, and the fabrication of extraction ducting for corrosive fumes.