Natural Surfactants-Based Ag Nanofluids for Enhanced Wettability on Hair Surface

摘要

The uses of natural products in personal care have increased gradually in recent years because of their nontoxic nature as compared to conventional chemical compounds. This study deals with the solution behaviors of three natural surfactants (Reetha, Shikakai, and Acacia) in the presence and absence of silver nanoparticles (Ag NPs) and their subsequent influence on the wettability of hair surface. Among all studied natural surfactants, Shikakai in the presence of Ag NPs showed the lowest contact angle 058.5), which was comparable to that of widely used synthetic surfactant TX-100 (similar to 57.2 degrees). The Ag NPs were synthesized by the chemical as well as in situ green routes in the presence of Acacia. The NPs and hair surface were characterized by transmission electron and atomic force microscopic techniques where the adherence of Acacia-mediated Ag NPs (average size of 24.17 nm) was observed over the rough surface of the hair strand. The reduction in surface tension from pure Acacia (similar to 43.56 mN/m) to in situ Ag NPs in Acacia media (similar to 41.6 mN/m) followed the increasing wettability at the virgin hair surface by lowering the contact angle from 105.5 degrees to 66 degrees. The chemically synthesized Ag NPs showed slightly better wettability (similar to 64.8) as compared to in situ Ag NPs in Acacia medium. However, the Acacia-mediated green synthesized Ag NPs suspension, despite being marginal inferior in terms of surface tension reduction and wetting, may be important from a practical perspective.