Measuring the Complex Modulus of Polymers by Instrumented Indentation Testing

Instrumented indentation is used to measure the complex modulus of highly plasticized polyvinyl chloride (HP-PVC) and four kinds of polyethylene over the frequency range of 1-50Hz. Over this range, the loss factor for the HP-PVC increases from 0.3 to 1, making this an ideal material for damping out noise and vibration. The storage moduli for the four polyethylene samples are ordered according to density, with the lowest-density material have the lowest storage modulus. Results for both storage modulus and loss factor compare well with published results obtained by dynamic mechanical analysis for nominally similar materials.