ABSTRACT
I. INTRODUCTION The microindenter is a device for detecting the temperature
at which the modulus of an amorphous polymer changes from a typical glassy value to a typical rubbery value. It requires a very small sample (c. 10 mg), can be used with heating rates comparable to those in DSC (i.e., 10°C/minute), and gives a large, clearly defined change at the glass transition. The essential features are a needle probe and a linear variable differential transformer (LVDT). By suitably controlling the force on the needle, the rate of heating, and the sample thickness, reproducible results can be obtained. The small sample size permits a relatively fast heating rate.
