Interfacial thermal conductance in spun-cast polymer films and polymer brushes

Department of Materials Science and Engineering, Frederick Seitz Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801, USA
Applied Physics Letters (Impact Factor: 3.3). 08/2010; 97(1):011908 - 011908-3. DOI: 10.1063/1.3458802
Source: IEEE Xplore


Interfaces between inorganic materials and anharmonic polymers have potentially intriguing thermal transport behavior. The low thermal conductivity of amorphous polymers limits significant interfacial effects to polymer film thicknesses of only a few nanometers. We use time-domain thermoreflectance to directly measure interfacial effects in the thermal conductance of spun-cast poly(methyl methacrylate) (PMMA) thin films and PMMA brushes “grafted-from” the substrate. PMMA brushes are expected to have polymer chains partially aligned perpendicular to the substrate, yet only a modest increase (13%) in thermal conductivity is observed over spun-cast layers.

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Available from: David G Cahill, Jan 06, 2015
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    • "An important goal in exploiting the high intrinsic thermal conductivity of certain polymers is to fabricate semi-crystalline polymers at a large scale. A morphology potentially suited to this purpose is the polymer brush, or an array of polymer chains attached at one or both ends to a substrate[13]. A promising synthesis technique, known as surface-initiated ring-opening metathesis polymerization (SI-ROMP), is able to uniformly grow tethered polymer chains from a substrate in the desired aligned structure. "
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