Mechanical property characterization of halloysite nanotubes/epoxy composites based on nanoindentation method

Halloysite nanotubes (HNTs) with different mass fractions, i.e. 0, 5wt% and 10wt%, were dispersed in epoxy using ball milling homogenization. And HNTs/epoxy composites were prepared using piperidine hardner. The elastic modulus, hardness and creep properties of HNTs/epoxy composites were determined using nanoindentation method. SEM and TEM observations show that HNTs are well dispersed in epoxy. Nanoindentation test results show that there is a significant increase in anti-creep properties of the epoxy matrix composites without sacrificing other properties such as elastic modulus, hardness and glass transition temperature of HNTs/epoxy composites. This is because the new network caused by interfacial bonding between HNTs and epoxy matrix chains could increase the cross linking density of materials, and the rigid nanoparticles restrict the mobility of the epoxy matrix chains.