Esterification reactions of mannitol with caprilic capric acid and its use in cosmetics

The cosmetic industry is experiencing continuous growth, leading to a proliferation of product diversity. Whereas cosmetics have once primarily associated with makeup products, today, they encompass a wide range of daily personal care items. This expanding variety of products in the cosmetic industry has prompted consumers to become more discerning and selective in their product choices. Consequently, there is a growing emphasis on the naturalness of products and the absence of factors that may negatively impact human health and the environment. The trend towards natural ingredients has spurred many sectors to explore the use of products derived from natural sources through emerging technologies. In line with this trend, the usage of esters, which offer pleasant fragrances and tastes, has become increasingly prevalent in the cosmetic industry. Notably, the ability of esters to be obtained through natural means and their biodegradability are among their greatest advantages for use in the cosmetic sector. Esters serve various purposes in cosmetics, including softening, thickening, emulsifying, lubricating, moisturizing, and odor removal. Esters formed through the esterification of mannitol, a plant-derived alcohol, with caprylic capric acid, a biodegradable fatty acid, belong to the category of valuable chemicals with high bioavailability. This study investigates esterification reactions of mannitol and caprylic capric acid at different mole ratios. Various catalysts such as phosphoric acid, para toluene sulfonic acid (PTSA), and methane sulfonic acid (MSA) have been employed in the reactions, and the effects of these catalysts on the reaction have been observed. An optimum temperature of 180°C was determined for all esterification reactions. The resulting products have been evaluated based on parameters such as acid number, viscosity, color, iodine value, HLB values, saponification numbers, reaction yield, and reaction time. Additionally, the products have been characterized using spectroscopic methods such as FTIR, GC.