Phonon Scattering in Polyethylene at Low Temperatures

摘要: An expression, valid below 4 \ifmmode^\circ\else\textdegree\fi{}K, for the phonon mean free path in polyethylene is derived through a consideration of microscopic structure. Above 1 scattering phonons occurs mainly within amorphous regions and can be described by structure term. The amorphous-crystalline boundaries contribute constant term to above but this temperature, when wavelength comparable size crystallites, it suggested that alternation crystalline material should second This shown account anomalous temperature variation thermal conductivity recently observed 1.5 \ifmmode^\circ\else\textdegree\fi{}K: No modification density states predicted Debye theory required. A discussion resonant also presented.