gamma-Alumina Modification with Long Chain Carboxylic Acid Surface Nanocrystals for Biocompatible Polysulfone Nanocomposites Articles uri icon

publication date

  • July 2014

start page

  • 14460

end page

  • 14468

issue

  • 16

volume

  • 6

International Standard Serial Number (ISSN)

  • 1944-8244

Electronic International Standard Serial Number (EISSN)

  • 1944-8252

abstract

  • High performance polysulfone/gamma-alumina biocompatible nanocomposites are reported for the first time and the effects of gamma-alumina surface modification are explored. We show that some fatty acids chemisorb over the surface of gamma-alumina forming nanosized self-assembled structures. These structures present thermal transitions at high temperatures, 100 degrees C higher than the melting temperatures of the pure acids, and are further shifted about 50 degrees C in the presence of polysulfone. The chemistry involved in the chemisorption is mild and green meeting the stringent bio sanitary protocols for biocompatible devices. It has been found that the self-assembled structures increase mechanical strength by about 20% despite the foreseeable lack of strong particle matrix interactions, which manifests as small variations in both the glass transition temperature and the Young's modulus. Electron microscopy observation of fractured surfaces has revealed that some acids induce an extended region of influence around the nanoparticles and this fact has been used to explain the enhancement of mechanical strength.

subjects

  • Chemistry
  • Materials science and engineering

keywords

  • alumina; fatty acids; nanocomposites; polysulfone; glass-transition temperature; mechanical-properties; polymer composites; homopolymer matrix; behavior; nanoparticles; morphology; interface; failure; silica