Several hierarchical nanophase-separated structures have been observed for a series of ABC star-shaped terpolymers by transmission electron microscopy (TEM) and electron computerized tomography (3D-TEM). The seven terpolymers synthesized are composed of polyisoprene (I), polystyrene (S), and poly(2-vinylpyridine) (P), their volume fraction ratios of I:S:P are 1:1:X, where X equals 0.2, 0.4, 0.7, 1.2, 1.9, 3.0, and 4.9, respectively, and additional four samples were prepared by blending each two parent terpolymers. From morphological observation by TEM and tomography, a terpolymer with X of 0.2 shows lamellar structure with spheres at the interface, those with X ranging from 0.4 to 1.9 show cylindrical structures with twodimensional tiling, while those with X of 3.0 and 4.9 show hierarchical cylinders-inlamella structure. Two the other terpolymer samples with X of 7.9 and 10 were produced by blending a P homopolymer with the terpolymer I 1.0 S 1.0 P 4.9 , and they both exhibited columnar piled disk cylinders in P matrix. From the comparison of the present results with the predictions by the Monte-Carlo simulation, it was confirmed that the observed nanophase-separated structures of the ISP star-shaped terpolymers are mostly in good agreement with the prediction.
The Melting of glass materials levitated in high magnetic fields has been carried
out without a crucible by using a hybrid magnet and a CO2 laser. A cubic glass with
6 mm sides has become a complete sphere through melting and cooling in the air. This
new method will provide opportunities for obtaining high-purity and new heterogeneous
materials.
Al+ ions have been implanted in silica glass at an acceleration energy of 200 eV and doses ranging from 1×1013 to 1×1017 ions cm−2. Infrared reflection spectra and ultraviolet, visible, and near-infrared absorption spectra have been measured. It was found that refractive index of silica glass increased by 6%–10% after implantation of 1×1017 Al+ ions cm−2. It was deduced that this refractive index change is caused by the formation of Si—Si homobonds, but not by the decrease in Si—O—-Si bond angle which leads to compaction.
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