%0 Report
%A Heyer, D.
%T Bestimmung der elastischen Konstanten von Polyäthylen
%V 1723
%N Juel-1723
%C Jülich
%I Kernforschungsanlage Jülich, Zentralbibliothek, Verlag
%M PreJuSER-136333
%M Juel-1723
%B Berichte der Kernforschungsanlage Jülich
%D 1981
%Z Record converted from JUWEL: 18.07.2013
%X This work reports the first direct determination of the microscopic elastic shear constants C$_{44}$ , C$_{55}$, C$_{66}$ and C' = $\frac{1}{4}$(C$_{11}$+C$_{22}$-2C$_{12}$ ) of crystalline polyethylene at room temperature. Fully deuterated and uniaxially oriented polycrystalline sampIes were used. The constants were obtained from a comparison of inelastic neutron scattering intensity profiles at low energy transfer near Bragg reflections with calculations in the long wavelength limit. The results are C44 = 2.1 $\pm$ 0.3 GPa, C$_{55}$ = 2.2 $\pm$ 0.3 GPa, C$_{66}$ = 1.46 $\pm$ 0.25 GPa and C' = 0.87 $\pm$ 0.25 GPa. Earlier macroscopic data can be derived satisfactorily from the measured constants assuming homogeneous stress in the sample.
%F PUB:(DE-HGF)29
%9 Report
%U https://juser.fz-juelich.de/record/136333