Effect of surface modification of fly ash on the mechanical, thermal, electrical and morphological properties of polyetheretherketone composites

Poly (ether ether ketone) (PEEK)/fly ash (FA) composites were prepared using melt blending technique. To improve the interfacial interaction of fly ash with the PEEK matrix, fly ash was chemically modified with calcium hydroxide, at different concentration. Various characterization studies like dynamic mechanical thermal analysis (DMTA), modulated differential scanning calorimetry (MDSC) and scanning electron microscopy (SEM) have been carried out to evaluate the storage modulus, tan δ, crystallinity, and morphology in the composites. SEM micrographs showed more uniform dispersion and interaction in the modified composites than unmodified counterpart. Surface modified fly ash improved the interfacial adhesion between fly ash and PEEK which is confirmed also through improved mechanical strength. The dynamic modulus of PEEK composites exhibited over 133% increment at 100–250 °C, indicating improvement of elevated temperature mechanical properties. The modified fly ash reinforcements also showed improvement in glass-transition and crystallization temperature.