Structural Analysis of Injection-Molded Polyoxymethylene Treated Below a Melting Point Using Field-Emission Scanning Electron Microscopy and Infrared Spectroscopy.

The heat treatment of an injection-molded polyoxymethylene slightly below the melting point and subsequent isothermal treatment at 130 °C were performed. The polyoxymethylene structure was examined using field-emission scanning electron microscopy and polarization infrared reflection measurements. After the heat treatment, a significant change in the surface morphology was observed, and the reflection spectrum derived from the polariton in the injection direction also changed dramatically.

Infrared active surface modes found in thin films of perfluoroalkanes reveal the dipole-dipole interaction and surface morphology.

Infrared (IR) spectra of an organic thin film are mostly understood by considering the normal modes of a single molecule, if the dipole-dipole (D-D) interaction is ignorable in the film. When the molecules have a chemical group having a large permanent dipole moment such as the C=O and C-F groups, the D-D interaction induces vibrational couplings across the molecules, which produces an extra band as a surface phonon or polariton band because of the small thickness. Since the dipole moment of an organic compound is much less than that of an inorganic ionic crystal, we have a problem that the extra band looks like a normal-mode band, which are difficult to be discriminated from each other.

Infrared Response of Sub-Micron-Scale Structures of Polyoxymethylene: Surface Polaritons in Polymers.

An investigation of the infrared (IR) spectra of polyoxymethylene (POM) mold plates was undertaken to determine the sub-micron-scale morphology and molecular orientation. The nest-structured cells concerned with the orientation were observed from scanning electron microscope (SEM) measurements with the aid of Raman spectroscopy. The intensity of the anomalous IR reflectance peak of the C-O stretching A2 mode depends on the widths of the POM layers in the SEM image along the orientation direction.

Structural analysis of mold temperature dependence of polycarbonate by mid-infrared spectroscopy.

The mold temperature dependence of bisphenol A polycarbonate (BPAPC) in the view of changing the "flexed state" was investigated by mid-infrared spectroscopy combined with a previously developed thin sample preparation system. The differences in the samples of different mold temperatures were clearly detected. The structural changes in the flexed state of each mold temperature were analyzed by comparing the results using dielectric function analysis of different cutting procedures.

A new approach to investigate thin surface layers of polymers: fatigue analysis of polycarbonate.

A new technique to investigate chemical structures of very thin surface (mesoscopic scale) layers of polar polymers is proposed. The chemical structures and conformations of ∼100 nm-thick slabs that were obtained from a polymer surface were studied by infrared spectroscopy combined with a previously developed thin sample preparation system. The dielectric functions were calculated using oscillator models from reflection spectra of the slabs, which were cut with a diamond blade.

Infrared surface analysis using a newly developed thin-sample preparation system.

We developed a new sampling system, the Nano Catcher, for measuring the surface chemical structure of polymers or industrial products and we evaluated the performance of the system. The system can directly pick up surface species whose depth is on the order of approximately 100 nm and can easily provide a sample for a Fourier transform infrared (FT-IR) system without the necessity of passing it over to a measurement plate. The FT-IR reflection data obtained from the Nano Catcher were compared with those obtained using the attenuated total reflection (ATR) method and sampling by hand.

Analysis of the inter-molecular interactions between amino acids and acetone by THz spectroscopy.

The THz spectra of amino acids after application of spots of acetone were measured. The 0.6 THz band was commonly observed in many amino acids that formed the intra-molecular salt structure.