Photodegradation Behavior of Kevlar 29 Fabrics against UV-Irradiation and the Effects of the Treatment with Water-Soluble Feather Keratin Derivatives on Both the UV-Irradiation-Induced Degradation of Kevlar 29 and the Enhancement in the Interaction at the Interface of Kevlar 29 Fiber-Feather Resin Composite

• Published in: Journal of textile engineering 2023-02, Vol.69 (1), p.9-15
• Main Authors: KAWAHARA, Yutaka, OHNO, Takeki, ITOI, Yuki, TAKADA, Yuto, YAMAMOTO, Masaki, WAKIZAKA, Hiroyuki, IKEDA, Yoshimitsu
• Format: Article
• Language: eng ; jpn
• Subjects: Aluminum; Aluminum chloride; Aluminum hydroxide; Aramid fiber reinforced plastics; Chlorides; Composite materials; Grooves; Hydrochloric acid; Irradiation; Kevlar (trademark); Modulus of elasticity; Photodegradation; Photosensitivity; Proteins; Resins; Stress propagation; Stress transfer; Tensile strength; Ultraviolet radiation; Water chemistry; Waterfowl
• ISSN: 1346-8235; 1880-1986
• DOI: 10.4188/jte.69.9

To reinforce the feather resin with Kevlar 29 fibers, the fibers were pretreated with the water-soluble protein derivatives prepared from the waterfowl feathers to cover the outer surface of the fibers. For this purpose, we used aluminum chloride hexahydrate for the pretreatment. When aluminum chloride hexahydrate is hydrolyzed in water, hydrochloric acid and aluminum hydroxide oligomer are generated. The former will work as an etching agent to form small pits or grooves on the fiber surface, and the latter will settle the protein derivatives on the fiber surface through chelate bonding. As a result, we succeeded in generating the insoluble stable coating on the Kevlar 29 fiber surface. This protein coating effectively reduced the photosensitivity of Kevlar 29 to the irradiation with ultraviolet (UV) rays, and fairly prevented the reduction in the tensile strength of the fibers. The photodegradation of Kevlar 29 fibers was found to proceed remarkably in the early stage of the irradiation with UV rays. It also changed the hue of the fibers. The feather resin reinforced with the protein-coated Kevlar 29 fibers exhibited an excellent sonic propagation speed, and a stress transfer coefficient resulted in 0.8 when the law of mixture was applied to the elastic modulus of the composite.