Melting points of crystalline/amorphous polymer blends, i. e., polyethyleneoxide (PEO)/polymethylmethacrylate (PMMA) blends, were investigated by differential scanning calorimetry (DSC) in order to investigate dependences on composition and molecular weights of both of crystalline and amorphous components. PEO showed depression of melting point by blending PMMA. According to the equation describing dependences of melting point of crystalline/amorphous polymer blend on composition and molecular weights of component polymers derived by Nishi and Wang, this fact apparently shows that this system is compatible polymer blend with negative value of the interaction parameter χ. However, the dependences on molecular weights of PEO and PMMA did not agree the equation derived by Nishi and Wang. These experimental facts suggested that melting point of crystalline/amorphous polymer blend should be discussed not only from the view point based on thermodynamics of equilibrium but also from the dynamical view point which takes into acount dynamical factor such as the mobility of polymer chain and so on.

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Thermal behaviour of the physical mixture of benzoic acid or p-hydroxybenzoic acid esters with heptakis-(2, 6-di-O-methyl)-β-cycladextrin (DMβCD) were investigated by differential scanning calorimetry (DSC). Two endothermic peaks were observed on the DSC curves, which were assigned to the inclusion formation and the release of the guest molecules from the inclusion compound by infrared spectroscopy and X-ray diffractometry.

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Crystallization process of polyethyleneoxide (PEO)/polymethylmethacrylate (PMMA) blends were investigated by differential scanning calorimetry (DSC) in order to investigate molecular weight dependences. The crystallization rate depended on the molecular weight of PMMA, Mw_PMMA, and became slow with increasing Mw_PMMA. However, the crystallization rate was independent of molecular weight of PEO, Mw_PEO. As for the activation energy for formation of secondary nucleus, it was unchanged by blending PMMA.

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Absorption/desorption of small amount of water and its effects on the phase transition at 146K in K₂ZnCl₄ were studies by FT-IR spectroscopy and adiabatic calorimetry. Existence of water molecule in absorbed crystal was substantiated by FT-IR spectra. It was verified by heat capacity measurements on single crystals of large size that the water is absorbed in the crystal. The reproducibility and reversibility of the absorption/desorption were confirmed by repeating heat/ventilation treatment and exposure of the sample to the laboratory atmosphere.

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Enthalpy changes of combustion (ΔH_c) of nonstoichiometric compounds for Ti-S, Cr-S and Ta-S systems were measured by using a Tian-Calvet type twin-calorimeter. The experimental conditions for combustion calorimetry were discussed from the standpoint of (a) temperature of calorimeter, (b) oxygen partial pressure, (c) particle size of sample, (d) amount of sample. The entalpies of phase transformation for Ti-S (4H- to 2H-TiS_x), Cr-S (trigonal- to rhombohedral-Cr₂S₃) and Ta-S (2S- to 3S- TaS_x, 3S- to 6S-TaS_x and 6S-TaS_x to 1S-TaS₂) systems were estimated. The relation between the ΔH_c of nonstoichiometric sulfides and the crystal structures were described.

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