Experimental Assessment of the Molecular Origin behind Yielding

Glassy polymers like atactic polystyrene (aPS) and polycarbonate (PC) are subjected to thermal ageing during processing and final usage. The consequence of this ageing effect is the significant rise of the yield stress and as a result the possibility of catastrophic failure. Even more interesting is the fact that if the aged glassy polymer is deformed into the plastic regime, the ageing effect disappears and the polymer behaves like an un-aged (young) material, this process is called “mechanical rejuvenation”. The aim of this project is to understand the molecular mechanism behind so-called mechanical rejuvenation and plastic deformation, and eventually even ageing itself, in an aPS employing X-ray methods.

Research type: experimental