Indentation Methods for Characterising the Mechanical and Fracture Behaviour of Polymer Nanocomposites
Keywords:fracture mechanics, hardness, indentation methods, polymer nanocomposite
Morphological analysis of nanocomposites of polyethylene glycol (PEG) based polyurethanes (TPU) and polyhedral oligomeric silsesquioxanes (POSS) were performed using different techniques (transmission electron microscopy, small and wide X-ray scattering, differential scanning calorimetry) as a function of molecular weight of PEG and the PEG/POSS mole ratio. A strong interdependence in crystallisation behaviour between the two crystals species, i.e. the POSS nanocrystals about 5 nm in size and the crystals in the semicrystalline soft phase of TPU, were found. The mechanical properties (Vickers hardness under load and elastic modulus) determined using recording microindentation techniques at room temperature were significantly improved by POSS for two material formulations. Based on the results of polymethylmethacrylate (PMMA)/silica (SiO2) nanocomposites containing up to 20 wt.-% well-dispersed spherical silica nanoparticles, it has been shown that the indentation fracture mechanics is a straightforward, costand time-effective, powerful tool to analyse the fracture resistance for the novel polymer materials, such as brittle nanostructured polymer-ceramic hybrids.
Nepal Journal of Science and Technology Vol. 13, No. 2 (2012) 115-122DOI: http://dx.doi.org/10.3126/njst.v13i2.7723
How to Cite
Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution-NonCommercial 4.0 International License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.