Poly(ether-ketone)/silica nanocomposites: Storage modulus and hardness

Dynamic mechanical properties of the poly (ether-ketone) (PEK) based nanocomposites reinforced with 0–30 wt% (0–20.2 vol%) SiO 2 nanoparticles (20–40 nm) were investigated at 1 Hz over the temperature range of 30°C–250°C for the application in printed circuit boards/electronic substrates. It was found that uniform dispersion of SiO 2 nanoparticles in the PEK matrix resulted in significant increase in storage modulus and microhardness. The highest increase in storage modulus measured at 50°C (glassy region) and 250°C (rubbery region) was more than 100% and 250% than that of neat PEK, respectively. The nanocomposites exhibited lower peak values of the tan δ than that of neat PEK. Scanning electron microscopy revealed good interfacial adhesion between the PEK matrix and the SiO 2 nanoparticles which was validated by Kubat parameter. The glass transition temperatures determined from the loss modulus and tan δ are slightly increased for the nanocomposites. However, differential scanning calorimetry could not detect glass transition temperature.