Optimization of experimental parameters in TMDSC - The influence of non-linear and non-stationary thermal response

To treat data from temperature modulated differential scanning calorimetry (TMDSC) in terms of complex or reversing heat capacity firstly one should p ay attention that the response is linear and stationary because this is a p rerequisite for data evaluation. The reason for non-linear and non-stationa ry thermal response is discussed and its influence on complex (reversing) h eat capacity determination is shown. The criterion for linear and stationar y response is proposed. This allows to choose correct experimental conditio ns for any complex heat capacity measurement. In the case when these condit ions can not be fulfilled because of experimental restrictions one can esti mate the influence of non-linearity and non-stationarity on measured value of complex or reversing heat capacity.