Design and fabrication of silica/chitosan composite microcapsules for bifunctional fabric coating

The design of biomass microencapsulated materials is garnering significant attention, with the achievement of multifunctionality and durability being crucial for their development. In this study, a multifunctional strawberry-like microcapsule based on a combination of chitosan and silica was prepared using a single coalescence method, which was then applied to fabrics to form multifunctional coatings. The UV absorber T1130-modified silica and the biomass material, chitosan, were encapsulated within a shell during the emulsion coalescence stage, while natural peppermint essential oil (PEO) served as the core material. This microcapsule design effectively combines the biocompatibility and antimicrobial properties of both substances, demonstrating 99.99 % and 93.10 % inhibition against E. coli and S. aureus, respectively. Additionally, the incorporation of UV-protective modified silica resulted in an Ultraviolet protection factor (UPF) value of 72.32 for the multifunctional fabric coatings. Furthermore, the morphological structure of the microcapsules, the release of core material, and the core-shell framework were characterized in this study. Moreover, the hybridization of bio-based organic with natural inorganic materials simplifies the preparation and functionalization process, making them environmentally friendly. The encapsulated PEO is released gradually over an extended period and exhibits relative stability under elevated temperatures. This study underscores the significant potential of bio-microcapsules in enhancing the multifunctionality of textile coatings.