Saturday, January 3, 2015

Thermally Conductive, Electrically Insulating and melt-processable Polystyrene/Boron nitride Nanocomposites Prepared by in situ Reversible Addition Fragmentation Chain Transfer Polymerization

ABSTRACT 

Thermally conductive and electrically insulating polymer/boron nitride (BN) nanocomposites are highly attractive for various applications in many thermal management fields. However, so far most of the preparation methods for polymer/BN nanocomposites have usually caused difficulties in the material post processing. Here, an in situ grafting approach is designed to fabricate thermally conductive, electrically insulating and post-melt processable polystyrene (PS)/BN nanosphere (BNNS) nanocomposites by initiating styrene (St) on the surface functionalized BNNSs via reversible addition fragmentation chain transfer polymerization. The nanocomposites exhibit significantly enhanced thermal conductivity. For example, at a St/BN feeding ratio of 5:1, an enhancement ratio of 1375% is achieved in comparison with pure PS. Moreover, the dielectric properties of the nanocomposites show a desirable weak dependence on frequency, and the dielectric loss tangent of the nanocomposites remains at a very low level. More importantly, the nanocomposites can be subjected to multiple melt processing to form different shapes. Our method can become a universal approach to prepare thermally conductive, electrically insulating and melt-processable polymer nanocomposites with diverse monomers and nano fillers.


The authors of this publication are on ResearchGate and have made the full-text available on their profilesDepartment of Physics, Michigan Technological University, 118 Fisher Hall, 1400 Townsend Drive, Houghton, MI 49931, USA. 
Nanoscale (Impact Factor: 6.73). 10/2010; 2(10):2028-34. DOI: 10.1039/c0nr00335b 
Source: PubMed