High Performance Polymers and Their Nanocomposites

Chapter 5Effect of Nanostructured Polyhedral Oligomeric Silsesquioxone on High Performance Poly(urethane-imide)

Dhorali Gnanasekaran

Dielectric Materials Division, Central Power Research Institute, Sir. C.V. Raman Road, Bangalore, India

Corresponding author: [e-mail]

Abstract

Polyhedral oligomeric silsesquioxones (POSS) were successfully embedded into poly(urethane-imide) membrane through chemical bonding, and the vital role of POSS on the surface morphology of prepared membranes was studied. A range of poly(urethane-imide)-POSS (PUI-POSS) membranes were prepared by a facile in situ polymerization reaction based on different loadings of POSS. The surface morphology structure of POSS incorporated membranes PUI-POSS were characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) techniques. The hydrophilic/hydrophobic nature and surface free energy of prepared membranes were analyzed by contact angle measurements using Sessile drop method. The thermal stability of PUI-POSS nanocomposite membranes was analyzed by thermogravimetric analysis (TGA). TEM images revealed the dispersion behavior of POSS into the membranes, and it was found to be in the range of 10–20 nm size. SEM images showed no agglomeration even at the higher content of POSS. Three-dimensional AFM images of the membranes indicated a slight increase in roughness when the POSS content was increased. The gel content, fractional free volume ...