HYSTERESIS, MODULUS ENHANCEMENT FACTOR AND STRESS-RELAXATION - A UNIQUE RELATIONSHIP

In this paper, a relationship between modulus enhancement factor (MEF) and hysteresis is reported for a very wide range of elastomers. The effects on MEF and hysteresis of a number of test and material variables have been studied, including for the former, compression strain level, loading rate and temperature, and for the latter, cross-linked and thermoplastic rubbers, with and without fillers. It has further been found that short term stress relaxation (up to 0.01 h) has the same basis as MEF and hysteresis for all the polymers covered in establishing the first part of the programme. Indeed relationships between MEF, hysteresis and the force relaxed at 0.01 h appear to be universal.