Generalized stress relaxation behaviour and physical aging in heterogeneous amorphous polyblends

Abstract

The influence of physical aging on viscoelastic behaviour of heterogeneous amorphous polyblends of ABS and polycarbonate was studied by means of stress relaxation experiments at different temperatures. The stress relaxation data of the constituent phases ABS and PC are found to be in agreement with the universal description of relaxation behaviour of amorphous polymers at the onset of the glass-rubber transition. The regimes where master curve construction by time-temperature and time-aging time superposition is permitted could be deduced for the thermorheologically complex polyblends. It is shown that the relaxation curves of the ABS/PC blends can be calculated by means of a quasi-elastic extension of the van der Poel-model using the stress relaxation data of the constituent phases and their volume fractions.