Adhesive interphase analyses of isotactic polypropylene and cyanoacrylate with cobalt complex primers

Swim bladder-derived biomaterials: structures, compositions, properties, modifications, and biomedical applications

Animal-derived biomaterials have been extensively employed in clinical practice owing to their compositional and structural similarities with those of human tissues and organs, exhibiting good mechanical properties and biocompatibility, and extensive sources. However, there is an associated risk of infection with pathogenic microorganisms after the implantation of tissues from pigs, cattle, and other mammals in humans. Therefore, researchers have begun to explore the development of non-mammalian regenerative biomaterials. Among these is the swim bladder, a fish-derived biomaterial that is rapidly used in various fields of biomedicine because of its high collagen, elastin, and polysaccharide content. However, relevant reviews on the biomedical applications of swim bladders as effective biomaterials are lacking. Therefore, based on our previous research and in-depth understanding of this field, this review describes the structures and compositions, properties, and modifications of the swim bladder, with their direct (including soft tissue repair, dural repair, cardiovascular repair, and edible and pharmaceutical fish maw) and indirect applications (including extracted collagen peptides with smaller molecular weights, and collagen or gelatin with higher molecular weights used for hydrogels, and biological adhesives or glues) in the field of biomedicine in recent years. This review provides insights into the use of swim bladders as source of biomaterial; hence, it can aid biomedicine scholars by providing directions for advancements in this field.

Surface Modification of Poly(ether ether ketone) through Friedel-Crafts Reaction for High Adhesion Strength

Poly(ether ether ketone) (PEEK) possesses attractive mechanical and thermal properties but demonstrates poor adhesion. To overcome this disadvantage, in this study, the surface modification of PEEK or PEEK-based carbon-fiber-reinforced thermoplastics (CFRTP) was performed through the Friedel-Crafts reaction and successive epoxidation. Under optimized reaction conditions, surface modification was achieved without surface deterioration, and epoxy groups were introduced. The progress of the Friedel-Crafts reaction and epoxidation was demonstrated by X-ray photoelectron spectroscopy measurements after fluorine labeling through thiol-en reaction and amine addition, respectively. The adhesive strength between CFRTP and epoxy adhesives was increased to 23.5 MPa, and cohesive fracture of epoxy adhesives, rather than interfacial peeling, occurred. In addition, compared with conventional plasma treatment, the durability of the modified surface and thickness of the modified surface layer increased. Therefore, we succeeded in modifying the surface properties through the epoxidation of the PEEK surface.