One-Pot Controllable Synthesis of Silica Nanocapsules with Encapsulated Osmanthus Fragrance for Durable Odor Improvement of Leather

Encapsulation of fragrance in micro/nanocapsules can preserve its own unique aroma in harsh environments and is the main way for leather perfuming to cover the peculiar odor of traditional leather products. Despite the success of post loading fragrance, limited consideration has been given to the tedious preparation procedures and the unacceptable loading efficiency. Herein, a highly efficient and straightforward one-pot loading method was developed to prepare osmanthus fragrance-silica nanocapsules (OF-SiO2 NCs) via hydrolysis and condensation reactions. The particle size could be easily controlled from 158 to 1063 nm with an OF loading efficiency of 10.2–18.7%, as desired by changing the solute content or altering the reaction temperature. Simultaneously, the above factors were found to affect the degree of ordered mesopores by promoting either the self-assembly of the surfactant–silica micelles or the condensation of the silica. The developed OF-SiO2 NCs were applied to perfume the cow leather-wet blue and sheep leather-dyed crust, which improved obviously the smelly odor. Moreover, up to two weeks of aromatic fragrance sustained release gave evidence of the highly incense retention time. These features highlight the potential use of OF-SiO2 NCs for aromatic leather products.