Drying oils coating formulations

Formation of peroxides by exposure to air and their involvement in polymerization processes is important for surface coating formulations containing polyunsaturated lipids called drying oils. Also nondrying oils, such as soybean oil, are under development as renewable sources for plastics and resins " . ... 

Hieh Solids. Great expectations are held for high-solids formulations, for industry s first coating was, in reality, a 100% solids system. Natural drying oils flowed easily, they pigmented easily, and they did not require baking in order to cross-link. The problem was chemical the oxidatively dried unsaturated species were not resistant to water, oxidative embrittlement, yellowing, and the like. 

Conventional air drying paints usually comprise alkyd oligomers as binders. These alkyds used in coating formulations are suitable for application at ambient temperature and are synthesised by a polycondensation reaction of polycarboxylic acids, polyhydric alcohols and unsatura fatty acids or oils (Figure 4). Highly suitable polycarboxylic acids include phthalic acid anhydride, terephthalic acid anhydride, trimellitic acid, adipic acid and maleic acid. 

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