OBJECTIVES To present a grading system of the protection offered by various types of mouthguard, together with an indication of associated risks, in order to make athletes aware of the consequences of improper or no mouth protection. METHODS A review of the literature on mouthguards, mouthguard materials, and novel laminates for mouthguards was carried out as it was apparent that information ...

L.K. Grunenfelder and S.R. Nutt 1. Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089-0241, USA *Corresponding author: [email protected] Abstract: Void formation as a function of resin moisture content was investigated to better understand and control process defects in composite parts made from prepreg. In this study, uncured prepr...

Block copolymers remain one of the most extensively studied and utilized classes of macromolecules due to their extraordinary abilities to (i) self-assemble spontaneously into a wide variety of soft nanostructures and (ii) reduce the interfacial tension between, and thus compatibilize, immiscible polymer pairs. In bilayered thin-film laminates of immiscible homopolymers, block copolymers are si...

Cross-ply laminates reinforced with basalt fibers and functionalized multi-walled carbon nanotubes (MWCNTs) were fabricated from unidirectional epoxy prepregs. MWCNTs with varied surface conditions were prepared by oxidization or esterification, and then dispersed into a DGEBA epoxy system. The dispersion of the MWCNTs in the epoxy was improved by surface modification, resulting in improved com...

Self-healing is receiving an increasing amount of worldwide interest as a method to autonomously address damage in materials. The incorporation of a self-healing capability within fibre-reinforced polymers has been investigated by a number of workers previously. The use of functional repair components stored inside hollow glass fibres (HGF) is one such bioinspired approach being considered. Thi...

In this paper, a method of solution and some numerical resu~s of free vibration and buckling of composite laminates are presented. All the edges of the laminates are assumed as simply supported. Ritz's method of solution is used with deflection surface expressed in terms of double series in Chebyshev polynomials satisfying the simply supported laminate boundary conditions. The numerical results...

Mode II delamination toughness of z-pin reinforced composite laminates is investigated using finite element (FE) method. The z-pin pullout process is simulated by the deformation and breakage of non-linear springs. A critical shear stress criterion based on linear elastic fracture mechanics is used to simulate crack growth in an end-notched-flexure (ENF) beam made of z-pinned laminates. The mod...

Electrical tomography can be used as a structural health monitoring technique to identify different damage mechanisms in composite laminates. Previous work has established the link between transverse cracking density and mesoscale conductivity of the ply. Through the mesoscale relationship, the conductivity obtained from electrical tomography can be used as a measure of the transverse cracking ...

This paper presents the results from an experimental study on the actuation response of composite laminates containing Shape-Memory Alloy (SMA) actuators. Unidirectional glassfibre reinforced epoxide laminates were constructed containing Ni-Ti SMA actuators orientated parallel to the glass-fibre direction. The volume fraction of actuator was varied in the range 0 to 2.5 ~ 0 1 % . These laminate...

The moisture absorption behavior and the influence of moisture on thermal and mechanical properties of glass–fiber/polyetherimide (PEI) laminates have been investigated. The laminates were exposed to hydrothermal aging at two different temperatures and high moisture rates. The properties of as-received and hydrothermally aged samples were compared. The hydrothermally aged laminates contained a ...