Anisothermal stress relaxation test for characterizing elastomers and polymers The Brabender- TSSR meter (TSSR = Temperature Scanning Stress Relaxation) measures the thermo-mechanical properties of elastomers and polymers subjected to a constant stress at a constantly rising temperature. The measuring data supply reliable information about the phase morphology of the material tested. Apart from that, this instrument allows to assess the modification of polymers with various additives and to determine the properties of such modified substances. The method The anisothermal stress relaxation test (AISR) is a new test method for characterizing the thermo-mechanical properties of elastomers and polymers. It consists in subjecting a test specimen to a constant tensile stress at a constantly rising temperature. The stress relaxation is measured as a function of time and is recorded and evaluated.