Synergistic effects of additives to benzotriazole solutions applied as corrosion inhibitors to archaeological copper and copper alloy artefacts
Benzotriazole (BTA) is a corrosion inhibitor extensively used for the stabilisation of active corrosion of archaeological copper and copper alloys. However, BTA often fails to effectively retard corrosion when applied on heavily corroded artefacts. Although there are numerous studies about its mode of action on clean copper, there is no comprehensive understanding about the way it is bonded to corroded copper. This thesis aimed to understand and compare BTA and its mode of action on clean and corroded copper by examining possible factors that could affect efficiency including concentration, solvent, period of immersion and pH. BTA efficiency could be improved by making use not only of these results but also of the synergism that is observed between BTA and other inhibitive compounds. The combination of inhibitors and the use of the synergistic effect between compounds is common in industry but has never been tested before for use in conservation. The synergistic effect could be beneficial for use on corroded copper alloys suffering with active corrosion. The six compounds selected were 5-Amino-2-Mercapto-l, 3, 4- Thiadiazole (AMT), Benzylamine (BZA), Ethanolamine (ET), l-Phenyl-5-Mercapto- Tetrazole (PMT),
Golfomitsou, S.
Synergistic effects of additives to benzotriazole solutions applied as corrosion inhibitors to archaeological copper and copper alloy artefacts. Benzotriazole (BTA) is a corrosion inhibitor extensively used for the stabilisation of active corrosion of archaeological copper and copper alloys. However, BTA often fails to effectively retard corrosion when applied on heavily corroded artefacts. Although there are numerous studies about its mode of action on clean copper, there is no comprehensive understanding about the way it is bonded to corroded copper. This thesis aimed to understand and compare BTA and its mode of action on clean and corroded copper by examining possible factors that could affect efficiency including concentration, solvent, period of immersion and pH. BTA efficiency could be improved by making use not only of these results but also of the synergism that is observed between BTA and other inhibitive compounds. The combination of inhibitors and the use of the synergistic effect between compounds is common in industry but has never been tested before for use in conservation. The synergistic effect could be beneficial for use on corroded copper alloys suffering with active corrosion. The six compounds selected were 5-Amino-2-Mercapto-l, 3, 4- Thiadiazole (AMT), Benzylamine (BZA), Ethanolamine (ET), l-Phenyl-5-Mercapto- Tetrazole (PMT),
effect solution apply corrosion archaeological copper copper_alloy artefact corrosion extensively used stabilisation active corrosion archaeological copper copper_alloy however often fail effectively retard corrosion apply heavily artefact although numerous study mode action clean copper comprehensive way bond copper aim compare mode action clean copper examine possible factor could affect efficiency include concentration period immersion efficiency could improve make_use also observe compound combination use effect compound common industry never test use conservation effect could beneficial use copper_alloy suffer active corrosion compound select