2017 年 90 巻 12 号 p. 557-564
This article summarizes the basic principles of differential scanning calorimetry (DSC) and temperature-modulated DSC (TMDSC) as well as the application of these techniques to polymeric materials or rubbers (elastomers). The determination of glass transition temperature Tg and the heat capacity difference ΔCp at Tg is crucial to elucidate the amorphous structure of polymers and polymer blends when using thermal analysis. In addition, enthalpy relaxation and thermal history must be considered in order to determine these thermal properties. In particular, TMDSC is a powerful technique to obtain highly sensitive and valuable information about the amorphous structure of polymers. The volume Vα of the cooperatively rearranging region of chloroprene rubbers was determined as a function of crystallinity using TMDSC. Based on the findings that the Vα decreases with increasing crystallinity, the amorphous region of chloroprene rubbers is suggested to be restrained by the cross-link of the crystal.
