Application of microencapsulation technology in silk fibers

Silk, a natural protein fiber, is top-rated with people as skin-friendly clothing for centuries. However, silk fiber (SF) still has disadvantages such as photo-induced aging and yellowing and wrinkling. Higher value, as well as novel and unique functions, are added according to the application of microencapsulation in the functional finishing of SF. By using microencapsulation technology, finishing agents, special functional materials, and so forth, can be encapsulated in polymer film-forming materials to form microcapsule finishing agents. Since the properties of the coated materials will not change after the formation of microcapsules, the functional materials can be protected. Only during processing or use, under the external environment such as pressure, friction, and temperature, can the microcapsules be ruptured or released through the diffusion effect of the microcapsule wall to achieve good and desired effects. In this review, recent developments in microencapsulation technology in the application of SFs are highlighted. First, the basic principle and technology of microencapsulation are introduced. Subsequently, adhesion between microcapsules and SFs are described. Finally, the application and effect of microencapsulation technology in SFs are summarized. In addition, the potential challenges and future prospects of microencapsulation technology in natural SFs are discussed.