[structure: see text] Non-aldol aldol rearrangement of the epoxy silyl ether 13b afforded the expected anti methyl ketone 14, while the diastereomeric epoxy silyl ether 13a afforded the syn methyl ketone 8b via an unprecedented syn hydride migration. Calculations suggest that this unusual reaction proceeds via the carbocation, which cannot easily rotate due to steric hindrance.

The influence of in-plane fiber waviness defects on the compressive properties quasi-isotropic (QI) carbon polyether-ether-ketone (C/PEEK) composites was investigated experimentally. Specimens with localized were manufactured using a stamp forming process resulting into laminates featuring multiple wavy plies, i.e. from one to three 0° plies in 24-ply QI composite and range maximum angle betwee...

Dynamically loaded structures made of thermoplastic polymers have been extensively exploited in several demanding industries. Due to the viscoelastic and thermal properties polymers, self-heating is generally inevitable, especially during dynamic deformations at high frequencies. Therefore, polyether ether ketone (PEEK), with its temperature resistance specific strength, a particularly ideal ca...

Hybrid joints consisting of metals and fiber-reinforced polymer composites exhibit highly desirable properties for many lightweight design applications. This study investigates the potential additively manufactured surface structures enhancing bond strength such in comparison to face milled laser structured surfaces. Titanium samples with different (as-built surface, groove-, pin-shaped structu...

Polyetheretherketone (PEEK) and thermoplastics nylon are extensively composed as an alternative material for removable denture base. The primary difference between the two materials is associated with water absorption properties. interact saliva microorganisms during application in oral cavity. Candida predominantly reported microorganism distinguished by its hydrophobicity ability to form biof...

Objective: The present study aims to investigate the mechanical properties of base materials [polymethyl methacrylate (PMMA)/polyether ether ketone (PEEK)] fabricated with computeraided design/computer-aided manufacturing (CAD/CAM) and heatpolymerized conventional materials. Material Methods: Two different polymers milled CAD/CAM (Yamahachi PMMA Disk Juvora Dental PEEK) heat-polymerized acrylic...

Abstract The direct blending of polyether ether ketone (PEEK) with a solid lubricant such as polytetrafluoroethylene (PTFE) improves its tribological performance, but compromises outstanding mechanical properties and processability. While these negative effects might be circumvented via the hybrid wear method, influence contact temperature between multiple sliding components acting together is ...