Modulating the morphology and protonation degree of chitosan coatings for enabling controlled fabric functionalization

Abstract

Chitosan (CS), a versatile biopolymer known for its diverse bioactivity, is commonly used as a coating or finishing agent to enhance fabric performance and broaden their applications. However, conventional methods for introducing CS coating layer on the fabrics often relies on using composition to control their functionality, limiting the ability to tailor properties for specific needs. In this study, we introduce an innovative coating platform utilizing drying, ionic gelation, or a combination of both to control the morphology and amino-protonation degree of CS. This approach allows the development of three distinct functional CS coatings from the same material composition. The method is effectively applied to cotton and polylactic acid (PLA)-based non-woven fabrics, preserving the permeability, breathability, and mechanical properties of the substrates. By varying processing conditions, it is found that CS coatings can impart distinct functions to the fabrics upon their morphology, such as attaining high degree of hydrophobicity (with a water contact angle reaching 129°), broad-spectrum antibacterial activity (>99.99 %) for the sample prepared by combined drying and ionic gelation methods. Additionally, our CS-coated fabrics can exhibit good biocompatibility, as demonstrated by cytocompatibility and histocompatibility evaluations, while excellent anti-adhesive properties and healing performance in infected wound models in rats can be obtained with the presence of CS microsphere. Our methods are straightforward and potentially scalable, enabling modular control over the functionality of CS-coated fabrics to meet diverse requirements. This work offers a promising strategy for modifying fabric properties with CS coatings, making it suitable for various applications such as facial masks, dressings, and antibacterial textiles.