The preparation and properties of polymer/nanoparticle blends using POSS (TM)

The synthesis of nanoparticle/polymer blends has expanded greatly in recent years. When the nanoparticles are ceramic, these blend materials have the advantage of combining a ceramic-type material with an organic polymer that can result in a material that may bridge the performance gap between the two systems. The Air Force Research Laboratory in collaboration with Michigan State University has been working with Polyhedral Oligomeric Silsesquioxanes (POSS) to enhance the performance characteristics of polymers. One aspect of this program is the preparation of POSS (TM)/polymer materials using traditional blending techniques. The authors have shown that simply changing the organic functionality around the POSS (TM) molecule can lead to POSS (TM) dispersion in a wide array of polymers, including polyethylene, polypropylene, polystyrene, polycarbonate, SB rubber, and many other polymers. In several cases the authors have been able to maintain clarity of the polymer after dispersion. By altering the organic side groups of POSS (TM) compounds to more compatible groups, one can fully disperse the POSS (TM) molecules into high molecular weight polystyrene and, in the case of StyrenylPOSS (TM)/polystyrene film, an increase of 30\% in the surface hardness is observed. Future work will focus on the use of POSS (TM) as a flame retardant. While vinyl 8T8 is not miscible in polystyrene, a partially functionalized vinyl 8T8 with aromatic groups should be. The concept of partial cross metathesis with vinyl 8T8 and styrene has been proven, and future work will focus on blends of these POSS (TM) compounds. Another possibility is the use of vinyl nTn as a reactive blendable with resins.