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The purpose of this paper is to reduce the amount of copper in antifouling paints by using eugenol as an additive. Biofouling leads to deterioration of any submerged material. The most widespread method for control is the application of cuprous oxide antifouling paints which are toxic. First of all, the paper describes the effect of eugenol on larvae of Balanus amphitrite (fouling organism) under laboratory conditions and then the preparation, application and performance of different types of antifouling paints in field trials.

Three types of soluble matrix antifouling paints were prepared with different pigments. The first one containing 16 per cent v/v copper, the second with 1.6 per cent copper and the third with 1.6 per cent copper + 2 per cent eugenol.

After 12 months of immersion in Mar del Plata harbour paints containing 1.6 per cent copper + eugenol and 16 per cent copper were the most effective. Although these formulations showed a similar performance, copper + eugenol-based paint contains 90 per cent lesser copper than a traditional copper-based formulation.

The use of antifouling paints with copper + eugenol combination as pigment is a promising alternative due to its performance, low cost and reduction in copper leaching to environment.

The effect of pigment filler and extender on the antifouling efficiency of six compositions containing organotin polymer is studied. The binder mixture is a blend containing a copolymer of tri‐n‐butyltin methacrylate and methylmeth acrylate (OTP) with 22% tin content, a vinyl copolymer with its external plasticizer and little amount of rosin. Cuprous oxide was added as a supplementary toxin with the OTP. Leaching rates of microamounts of copper and tin were determined for a period of nearly one year applying standard techniques. Painted plates were immersed in Suez Canal waters at Port‐Said for more than 36 months. Comparison between different fillers and extenders on the antifouling behaviour of painted surfaces is shown. Compositions containing cellite and china clay exhibited the maximum antifouling performance.

The purpose of this paper is to develop protective coatings containing antifouling compound for steel rebars.

In the present study, corrosion and settlement of micro and macro‐fouling organisms on coated and uncoated rebars were investigated. Two different types of coatings were applied: only primer for prevention of corrosion; and rosin‐based antifouling paint after application of primer.

According to results, the surfaces of the rebars coated by antifouling paints were remarkably cleaner than were those of uncoated and primer‐coated steels. Micro and macro‐organisms that settled on the rebars were identified after 90 days of seawater immersion in Izmir, Turkey.

The paper contributes to scientific literature by providing a protection method based on the use of antifouling coatings for steel rebars used in marine environments (e.g. bridge piers). It was concluded that steel rebars can be coated with antifouling paints before they are used for concrete constructions.

Since the dawn of history, when man first put to sea, he has been fighting a constant battle: waged not against a powerful adversary or even the elements, but against an array of seemingly insignificant sea creatures. These organisms create the nuisance of marine fouling.

An organotin copolymer with tin content of 22% was prepared by the reaction of methyl methacrylate and tri‐n‐butyltin methacrylate. The prepared copolymer was incorporated into a paint formulation containing cuprous oxide as an external toxin. Laboratory evaluation of the formulation showed that the average value of the leaching rate of Cu was 7 µg/cm2/day, while the leaching rate of tin was found to be in the range of 0.033 µg/cm2/day. The antifouling performance of the prepared formulation was tested as painted areas on the hull of a trading ship. After about one year's running period through the Mediterranean and Red Sea harbours the tested areas showed good antifouling efficiency compared with the commercial antifouling paint.

The method has been previously reported on in NSFI‐Nytt Nos. 1 and 3, 1973. The term ‘re‐activation of antifouling’ is not particularly good as it suggests merely the intention of keeping the ship free of growth by keeping the antifouling active, whereas the intention is to prevent all forms of roughening, i.e. also those caused by the formation of blisters, paint peeling, painting over stubs of old growths, under‐rusting etc.

Spot test methods were used for the qualitatative detection of the presence of Cu, lead and tin compounds in the antifouling paints leachates. Laboratory prepared antifouling paints were used as a guidance for the detection of these compounds. The methods were applied for commercial antifouling paints and gave promising results.

The use of triorganotin compounds as successful antifouling agents for use on seagoing vessels is well established. In particular the tributyltin and triphenyltin compounds are very effective toxicants to the most common type of fouling organisms such as barnacles, sea grass, molluscs and sponges. Organotin‐based antifouling coatings can be applied in a number of ways. The most common system of application is with the chemical antifouling compound physically mixed into paint. Diffusion of the organotin compound to the coating surface then takes place, and it is released into the water; with this method the rate of release of the toxicant decreases over a period of time and eventually the coating has to be replaced. An alternative method of dispersing the toxicant is from a polymer coating formulated by chemically binding the organotin molecules to a polymeric binder in the paint. In this method a ‘controlled release’ of the toxicant is achieved, with a constant rate of release of the compound over a period of time, so that an effective toxic concentration is maintained. Organotin‐based antifouling agents have increased in popularity in recent years, as the lifetime of these coatings is longer than the traditional copper oxide‐based products. In the long term, therefore, organotin‐based coatings are cheaper to use. In addition, these coatings do not present an environmental hazard, as the organotin decomposes to a non‐toxic inorganic tin compound.

To organotin polymer systems were prepared based on the reaction of tri‐n‐butyltin methacrylate with methyl methacrylate ad acrylonitrile. Tin content of the polymers was about 22% and the physical properties of the organotin polymer films were investigated. The anti‐fouling potential of the prepared polymers was investigated as unpigmented and pigmented coatings at Alexandria and Port‐Said. Compositions containing vinyl copolymer as a co‐resin as well as cuprous oxide as a supporting toxin showed good antifouling performance for more than three years.

Two sets of formulations based on three copolymer and three terpolymer systems involving tributyltin methacrylate(BTMA),methyl methacrylate(MMA) and acrylonitrile (AN) with variable tin contents of 7, 15 and 22% were prepared. There is only one varient in each formulation of the six prepared, that is the type of organotin polymer whether it is a copolymer or terpolymer of a definite tin content 7 or 15 or 22%. The binder mixture is a blend consisting of the organotin polymer, a vinyl copolymer and its external plasticizer and little amount of rosin. A moderate and fixed amount of cuprous oxide was introduced into all formulations as a supplementary toxin with organotin polymer. Leaching rates of micro amounts of copper and tin were determined. Panel exposure test in the sea was performed at Port Said. Best antifouling efficiency was obtained from formultions containing organotin copolymer or terpolymer of 22% tin content and that containing organotin copolymer of 15% tin.