The Glass Transition of Amorphous Polymers and the Free Volume

摘要: Linear viscoelastic shear behaviour of amorphous polymers obeys the time temperature superposition principle, as has been known for more than thirty years1)2). This principle states that characteristic functions measured at different temperatures may be brought to coincide by parallel shifts along logarithmic or frequency axis. If, instance, J(t,T) represents creep compliance a function t T, compliances T and To should connected relation $$ = a\left( {T,{T_{O}}} \right) $$ (1) where $$ (2) is only. log a(T,To) is shift applied axis obtain superposition. It called time-temperature function.