Hybrid glass fibre reinforced composites with micro and poly-diallyldimethylammonium chloride (PDDA) functionalized nano silica inclusions

• PDDA facilitates the nanoparticle dispersion within the epoxy polymer.
• The stiffness of HGFRC and epoxy polymer was increased by silica particle inclusions.
• The tensile strength/modulus of HGFRCs was enhanced by nano-sized silica inclusions.
• The flexural modulus of HGFRC was increased by silica inclusions.
• The tensile modulus of epoxy polymer was enhanced by nano silica incorporation.

This work investigates the effect of using functionalised poly-diallyldimethylammonium chloride (PDDA) silica micro and nanoparticles on the apparent density, tensile and flexural strength and modulus of hybrid glass fibre reinforced composites. The work is carried out using a Design of Experiment (DoE) approach on a population of 60 composite specimens produced according the size of the nanoparticles and their weight fraction. A 2% of weight fraction of functionalised silica nanoparticles is shown to reduce the flexural strength and density of the composites, but to maximise significantly both the tensile, flexural modulus and tensile strength of the hybrid glass fibre materials.