Netsu Sokutei

The Simultaneous DSC-FTIR Study on the Isothermal Crystallization and the Multiple Melting Behavior of the Partially Miscible Poly (vinyliden fluoride) Blends

Gong Zheng Zhang, Takamasa Kitamura, Tadashi Kawai, Hirohisa Yoshida

2002 Volume 29 Issue 5 Pages 192-198
Published: December 05, 2002
Released on J-STAGE: September 07, 2009

DOIhttps://doi.org/10.11311/jscta1974.29.192

JOURNAL FREE ACCESS

Show abstractHide abstract

Isothermal crystallization and melting behaviors of poly (vinilidene fluoride) (PVDF) and isotactic poly (methyl methacrylate) (isoPMMA) blend, partially soluble blend system, were investigated by the simultaneous DSC-FTIR method. The absorption bands at 795 and 810cm^-1, which were assigned respectively to CH₂ rocking vibration mode of PVDF in TGTG' (α-form) and T₃GT₃G'(γ-form) conformation, were used as an indication of each crystal form. During the isothermal crystallization, the α-form crystallized in the initial stage of crystallization, γ-form crystallized after the maximum of α-form content. The transition mechanism from α-form to γ-form was estimated from the linear relationship between IR absorbance corresponding to the decrease rate of α-form and the increase rate of γ-form. The γ-form was transformed from the α-form in the solid state for the blends with PMMA content (φ_PMMA) lower than 0.2, and the γ-form was crystallized from the super-cooled liquid state addition with the solid state transition from the α-form for PVDF. The multiple melting peaks were observed by heating immediately after isothermal crystallization. Each melting peaks were identified as the melting of α-form, the melting of γ-form produced by the melt-recrystallization of α-form, and the melting of γ-form transformed from α-form in the solid state during the isothermal crystallization.

View full abstract

Download PDF (2000K)
The Experiments on Mechanical Equivalent of Heat by J. P. Joule

Masashi Okamoto

2002 Volume 29 Issue 5 Pages 199-207
Published: December 05, 2002
Released on J-STAGE: September 07, 2009

DOIhttps://doi.org/10.11311/jscta1974.29.199

JOURNAL FREE ACCESS

Show abstractHide abstract

Physics textbooks show Joule's paddle-wheel equipment in 1850 in relation to the law of conservation of energy, but describe nothing about the background of his experiments. Joule had made many kinds of experiments to determine mechanical equivalent of heat for a long period from 1843 to 1878. Unfortunately, academic society had not appreciated his early studies, because the concept of calorique had still prevailed in the middle of 19c. Even after clear evidence was presented, it takes a long time for the society to recognize a new scientific knowledge. This is a social nature of science, which should be emphasized in scientific education.

View full abstract

Download PDF (1871K)
Time-resolved Measurements of Thermodynamic Quantities and Applications

Masahide Terazima

2002 Volume 29 Issue 5 Pages 208-216
Published: December 05, 2002
Released on J-STAGE: September 07, 2009

DOIhttps://doi.org/10.11311/jscta1974.29.208

JOURNAL FREE ACCESS

Show abstractHide abstract

Although the thermodynamic quantities are very fundamental and important quantities to describe chemical states, these quantities have been studied only under the equilibrium condition. This limitation was a serious problem for understanding transient chemical processes including photochemical reactions. One challenge facing chemists studying chemical reactions is to obtain thermodynamic information about non-equilibrium states involved in rapid reactions. Several methods we have developed recently for the measurement of the time-resolved thermodynamic quantities were reviewed. Using these methods, we are now able to measure the initial step of the heating process due to the nonradiative transition, enthalpy of reaction, partial molar volume change, thermal expansion coefficient, and heat capacity of transient species.

View full abstract

Download PDF (1686K)
Density and Sound Velocity Measurements of Mixtures

A Viewpoint of Molecular Shapes and Orientations Owing to Non-isotropic Interactions

Katsutoshi Tamura

2002 Volume 29 Issue 5 Pages 217-224
Published: December 05, 2002
Released on J-STAGE: September 07, 2009

DOIhttps://doi.org/10.11311/jscta1974.29.217

JOURNAL FREE ACCESS

Show abstractHide abstract

Molecular shape and dipole moment causing non-isotropic interactions are very important for analyzing the mixing states of liquid mixture. They affect the curves of excess volume, excess isentropic and isothermal compressibilities, and the other excess properties through the molecular packing in both the mixtures and the pure liquids. Molecules far from a simple globule orient in unfavorable ways to make their volumes increase in mixtures and pure liquids, and flexible linear molecules squeeze into the room arisen from the packing of bulky molecules. Dipole moments on the molecules orient in the way restricted by various molecular shapes.

View full abstract

Download PDF (1301K)
[title in Japanese]

2002 Volume 29 Issue 5 Pages 225
Published: December 05, 2002
Released on J-STAGE: September 07, 2009

DOIhttps://doi.org/10.11311/jscta1974.29.225

JOURNAL FREE ACCESS

Download PDF (166K)
Thermomechanical Analysis of Hydrogels in Water

Mika Iijima, Tatsuko Hatakeyama

2002 Volume 29 Issue 5 Pages 226-227
Published: December 05, 2002
Released on J-STAGE: September 07, 2009

DOIhttps://doi.org/10.11311/jscta1974.29.226

JOURNAL FREE ACCESS

Download PDF (754K)
The Development for Gelled Ink Roller Ball Pen

S. Inoue

2002 Volume 29 Issue 5 Pages 232-233
Published: December 05, 2002
Released on J-STAGE: September 07, 2009

DOIhttps://doi.org/10.11311/jscta1974.29.232

JOURNAL FREE ACCESS

Download PDF (771K)

Register with J-STAGE for free!