Characterization of poly(ethylene oxide) modified with different phenyl hepta isobutyl polyhedral oligomeric silsesquioxanes

Poly(ethylene oxide)/polyhedral oligomeric silsesquioxanes (PEO/POSSs) composites were prepared by the melting method. The investigation of their thermal characteristics was performed by the differential scanning calorimetry (DSC), while the investigation of their thermal stability was performed by the non-isothermal thermogravimetry. The glass transition temperatures, the crystallinity and the melting temperature of PEO decrease with the addition of POSS nanoparticles. FTIR analysis also confirms the decrease in PEO’s crystallinity with the addition of POSS. POSS nanoparticles shift the beginning of PEO decomposition toward lower temperatures, while they do not have a significant effect on the maximum decomposition temperature, maximum decomposition rate and the residual mass. Scanning electron microscopy analysis seems to indicate that a poor dispersion of POSS nanoparticles causes this worsening in the thermal behavior of the prepared composites. The non-isothermal decomposition of PEO/POSSs samples is more complex compared to pure PEO. POSS nanoparticles influence the beginning of the PEO’s decomposition process and its activation energy, while the kinetic model of PEO’s thermal decomposition process remains unchanged.