An investigation of the material properties and the fibre-matrix interfacial shear strength in glass fibre epoxy and acrylic composites

The material properties of fibre-reinforced composite materials are highly dependent upon the ability of the fibre-matrix interface to transfer stresses between the constituents. This interfacial shear strength (IFSS), an accepted mechanically measurable value for quantifying fibre-matrix adhesion, between the fibres and matrix is highly influential on the performance of the composite and as such characterisation of the IFSS is critical for understanding composite performance [1]. In the present work thermal analysis of novel thermoplastic Elium191® acrylic was undertaken using a combination of Differential Scanning Calorimetry (DSC) and Dynamic Mechanical Analysis (DMA) to study the key material properties tied towards potential residual stress build-up at the fibre matrix interface, including glass transition temperature and storage modulus [2, 3, 4]. Droplets of Bisphenol-A diglycidyl ether (DGEBA) epoxy/triethylenetetramine (TETA) and Elium191® acrylic were applied to multi-compatible sized glass fibres and the IFSS determined using a microbond test to allow for comparisons between the two systems compared, in preparation for further study focused on the effects of humidity and moisture content the fibre matrix interface level.