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941.
942.
Charge-induced infrared absorption spectra from the metal-insulator-semiconductor diodes fabricated with aluminum oxide, poly(p-xylylene), and SiO2 as gate dielectric and regioregular poly(3-octylthiophene) as organic semiconductor have been measured in situ with reflection or transmission configurations by the FT-IR difference-spectrum method. The observed bands have been attributed to the carriers injected into the polymer layers under the application of minus gate bias. The wavenumber of the band around 1300 cm−1 depends on the gate voltage, indicating that the structure of the carriers depends on the carrier concentration. There exist upper limits in the concentrations of the injected carriers. In situ infrared absorption measurements provide the information about the injected carriers, which affect the properties and the functions of polymer field-effect devices. 相似文献
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945.
Yukio Yamaguchi Brian C. Hoffman Jeffrey C. Stephens Henry F. Schaefer III 《ChemInform》1999,30(51):no-no
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献
946.
Yukio Nagasaki Noriyuki Yamazaki Ken-Ichiro Deguchi Masao Kato 《Macromolecular rapid communications》1996,17(1):51-58
Several types of poly(silamine)s were prepared and their structure-characteristics relationships were investigated. When a phenyl ring in the organosilyl unit and/or a cyclic structure in the amino unit was introduced, the glass transition temperatures were increased significantly in order to increase film formability. From the thermogravimetric analysis of the poly(silamine)s, it was found that the thermal decomposition of poly(silamine)s starts at ca. 380–400°C. On electron-beam irradiation of the poly(silamine) films, degradation of the polymer took place. On the basis of these results, poly(silamine)s can be one of the candidates for new positive-type polymeric resists. 相似文献
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949.
Copolymerization of ethylene and 1,5-hexadiene (HD) by zirconocene catalysts proceeded via cyclization-addition mechanism to form 1,3-didsubstituted cyclopentane structure in the polyethylene chain. The 1,3-cyclopentane structure was found to be taken in the crystalline structure of polyethylene (isomorphism) by partially chainging the trans zigzag chain into gauche conformation, thereby, inducing a transformation of orthorhombic crystal to pseudohexagonal crystal. Copolymerization of ethylene and cyclopentene (CPE) by zirconocene catalysts yielded copolymers having 1,2-disubstituted cyclopentane structure in the polyethylene chain. The 1,2-cyclopentane structure was not taken into the crystalline structure of polyethylene. The melting point (Tm) and the crystallinity (Xc) of polyethylene decreased by copolymerization of HD or CPE, and the Tm- and Xc-decreasing effect of CPE was stronger than HD. For copolymers of propylene and HD or CPE obtained with isospecific zirconocene catalyst, the isomorphism was not ovserved. 相似文献
950.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献