scholarly journals TEM Studies on Thin Films of Natural Rubber and Polychloroprene Crystallized under Molecular Orientation

1999 ◽  
Vol 31 (9) ◽  
pp. 784-789 ◽  
Author(s):  
Masaki Tsuji ◽  
Toshiki Shimizu ◽  
Shinzo Kohjiya
Keyword(s):  
Thin Films ◽  
Natural Rubber ◽  
Molecular Orientation

TEM Observation of Natural Rubber Thin Films Crystallized under Molecular Orientation

2000 ◽  
Vol 73 (5) ◽  
pp. 926-936 ◽  
Author(s):  
Toshiki Shimizu ◽  
Masatoshi Tosaka ◽  
Masaki Tsuji ◽  
Shinzo Kohjiya
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Natural Rubber ◽  
Isothermal Crystallization ◽  
Molecular Orientation ◽  
Benzene Solution ◽  
Dark Field ◽  
In Situ Tem ◽  
Time Resolved ◽  
Specimen Holder

Abstract Morphology of natural rubber (NR) thin films crystallized under molecular orientation was examined by transmission electron microscopy (TEM). A thin film of NR (RSS#1) was made by casting its n-hexane (or benzene) solution onto the water surface, and prestretched up to a desired amount of strain (%). Each of the specimens thus prepared was introduced into a TEM column and isothermally crystallized at −25 °C with a cryo-transfer specimen-holder. Morphological observations in bright- and dark-field imaging modes revealed directly that the length of the lamellae, which were oriented perpendicular to the stretching direction, decreased with increasing strain. The result seems to be related to the population density of “γ-filaments” (named by Andrews) generated only by prestretching. Time-resolved bright-field observations by in situ TEM of the thin film prestretched up to a strain of 200% revealed the following. Though the film gave crystalline reflections in its selected-area electron diffraction even before isothermal crystallization, no well-defined lamellae were recognized. Subsequent isothermal crystallization for 2 h, however, formed well-defined lamellae oriented perpendicular to the stretching direction. This observation, conceivably, suggests that “γ-filaments” were formed immediately by prestretching and then the lamellae were nucleated on the γ-filaments at −25 °C.

scholarly journals A TEM STUDY ON NATURAL RUBBER THIN FILMS CRYSTALLIZED UNDER MOLECULAR ORIENTATION

1998 ◽  
Vol 47 (6Appendix) ◽  
pp. 117-120 ◽  
Author(s):  
Toshiki SHIMIZU ◽  
Masaki TSUJI ◽  
Shinzo KOHJIYA
Keyword(s):  
Thin Films ◽  
Natural Rubber ◽  
Molecular Orientation

Molecular orientation of oligothiophene-based polyamide thin films fabricated by vapor deposition polymerization

2002 ◽  
Vol 405 (1-2) ◽  
pp. 77-80 ◽  
Author(s):  
Hitoshi Muguruma ◽  
Kazutoshi Matsumura ◽  
Shu Hotta
Keyword(s):  
Thin Films ◽  
Vapor Deposition ◽  
Molecular Orientation

PTCDA Films Deposited by Ionized Beam Method

1993 ◽  
Vol 316 ◽  
Author(s):  
Hiroaki Usui ◽  
Kiyoshi Kashihara ◽  
Kuniaki Tanaka ◽  
Seizo Miyata
Keyword(s):  
Thin Films ◽  
Molecular Orientation ◽  
Chemical Structure ◽  
Chemical Change ◽  
The Other ◽  
Ion Acceleration ◽  
Ionization Condition ◽  
Other Hand ◽  
Beam Method

ABSTRACTThin films of 3,4,9,10-perylenetetracarboxylic-dianhydride (PTCDA) were deposited by an ionized beam method. The molecular orientation and chemical structure of the films were studied in connection with ionization and ion acceleration conditions. At a low ionization condition, the molecules are oriented in parallel with the substrate, and the crystallinity was improved by an appropriate ion acceleration. At higher ionization conditions, on the other hand, ion acceleration resulted in a loss of crystallinity. Deposited molecules undergo chemical change in such a condition, leading to dissociation of dianhydride groups.

Molecular Orientation Change in Naphthalene Diimide Thin Films Induced by Removal of Thermally Cleavable Substituents

2019 ◽  
Vol 31 (5) ◽  
pp. 1729-1737 ◽  
Author(s):  
Tomoya Nakamura ◽  
Nobutaka Shioya ◽  
Takafumi Shimoaka ◽  
Ryosuke Nishikubo ◽  
Takeshi Hasegawa ◽  
...  
Keyword(s):  
Thin Films ◽  
Molecular Orientation ◽  
Orientation Change ◽  
Naphthalene Diimide

TO-LO Splitting in Infrared Spectra of Thin Films

1996 ◽  
Vol 50 (6) ◽  
pp. 759-763 ◽  
Author(s):  
Kiyoshi Yamamoto ◽  
Akio Masui
Keyword(s):  
Thin Films ◽  
Infrared Spectra ◽  
Molecular Orientation ◽  
Peak Position ◽  
Peak Shape ◽  
Surface Phenomena ◽  
Longitudinal Optic ◽  
Transverse Optic ◽  
Optical Behavior ◽  
Optical Calculation

The importance of transverse optic-longitudinal optic (TO-LO) splitting in the interpretation of infrared spectra of thin films is experimentally presented. When infrared spectra are observed at oblique angles of incidence, the shifts in peak position and/or the changes in peak shape may be due to TO-LO splitting. Before one assigns the optical behavior to surface phenomena such as molecular orientation, proper care must be employed. The proposed technique includes optical calculation to extract surface phenomena from TO-LO splitting in the spectra, and it is applied to reflection absorption spectra of perfluoropolyether.

Molecular orientation of copper phthalocyanine thin films on different monolayers of fullerene on SiO2 or highly oriented pyrolytic graphite

2015 ◽  
Vol 106 (12) ◽  
pp. 121603 ◽  
Author(s):  
Chenggong Wang ◽  
Xiaoliang Liu ◽  
Congcong Wang ◽  
Xumei Xu ◽  
Youzhen Li ◽  
...  
Keyword(s):  
Thin Films ◽  
Molecular Orientation ◽  
Copper Phthalocyanine ◽  
Pyrolytic Graphite ◽  
Highly Oriented Pyrolytic Graphite
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