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Health and Safety Aspects in the Use of Metalworking Fluids
Published in Jerry P. Byers, Metalworking Fluids, Third Edition, 2018
Most often, more than one causative factor is responsible for cases of contact dermatitis. Also, additives such as amines, petroleum sulfonate, and some biocides have been associated with the diagnosis of contact dermatitis. Skin sensitization, which is an allergic response to a chemical or a component in a fluid, has also been reported. Some biocides and corrosion inhibitors, including isothiazalones, formaldehyde, and mercaptobenzothiazoles, have been reported to have sensitization potential. Metal allergy dermatitis may also occur due to the dissolution of small amounts of metallic ions from some alloys being machined. Nickel and chromium, found in stainless steels, and cobalt, used as a binder in tungsten carbide tooling, are three of the most common metal skin sensitizers.
Immobilization of polyphosphoesters on poly(ether ether ketone) (PEEK) for facilitating mineral coating
Published in Journal of Biomaterials Science, Polymer Edition, 2019
Shun Kunomura, Yasuhiko Iwasaki
Recently, titanium-based and cobalt-chrome alloys have been widely used in biomedical implants [1, 2] due to their excellent strength and toughness. Furthermore, several surface modification techniques have been proposed to obtain hard-tissue compatibility [3, 4]. However, metallic implants cause complications such as transient osteoporosis of the hip due to stress shielding, metal allergy, and fatigue fracture [5–7]. To reduce these unfavorable issues, poly(ether ether ketone) (PEEK) has gained interest a new candidate for biomedical and orthopedic implants [8–13]. The Young’s modulus of PEEK (4 GPa) is lower than that of cortical bone, whereas carbon-reinforced PEEK (CFR-PEEK) and cortical bone have similar Young’s moduli [14, 15]; thus, CFR-PEEK implants may avoid stress shielding effects, thereby avoiding bone loss. PEEK is durable and highly resistant to creep and fatigue [8, 16]; thus, it is a reliable material for medical uses. However, the surface properties of PEEK must be improved to generate suitable interfacial aspects, such as non-fouling, lubricity, and tissue compatibility, depending on the intended uses.