ADVERTISEMENT RETURN TO ISSUECommunication to the...Communication the EditorNEXTNanoporous Polyethylene Film Prepared from Bicontinuous Crystalline/Amorphous Structure of Block Copolymer PrecursorHiroki Uehara, Tomoyuki Yoshida, Masaki Kakiage, Takeshi Yamanobe, Tadashi Komoto, Kumiko Nomura, Katsuhiko Nakajima, and Masatoshi MatsudaView Author Information Department Chemistry, Gunma University, Kiryu, 376-8515, Japan, Material Engineering Division, Toyota Motor Corp., Toyota, Aichi...

Morphological effects on molecular mobility have been studied for solid ultrahigh weight polyethylenes (UHMW-PE) crystallized from the melt and solution or during polymerization. On basis of transmission electron microscopic (TEM) observation, a crystalline domain structure was well identified nascent UHMW-PE powders, which is quite different regular lamellar stacking solution-crystallized samples usual spherulites melt-crystallized samples. Nuclear magnetic resonance (NMR) results showed...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTConformation of cyclic paraffins and polyethylene in the solid state as studied by carbon-13 CP/MAS NMRIsao Ando, Takeshi Yamanobe, Tetsushi Sorita, Tadashi Komoto, Hisaya Sato, Kenzo Deguchi, Mamoru ImanariCite this: Macromolecules 1984, 17, 10, 1955–1958Publication Date (Print):October 1, 1984Publication History Published online1 May 2002Published inissue 1 October 1984https://doi.org/10.1021/ma00140a013RIGHTS & PERMISSIONSArticle...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTConformation and dynamic aspects of poly(.gamma.-n-octadecyl L-glutamate) in the solid state liquid-crystalline as studied by variable-temperature carbon-13 CP/MAS NMR spectroscopyTakeshi Yamanobe, Makoto Tsukahara, Tadashi Komoto, Junji Watanabe, Isao Ando, Ichitaro Uematsu, Kenzo Deguchi, Teruaki Fujito, Mamoru ImanariCite this: Macromolecules 1988, 21, 1, 48–50Publication Date (Print):January 1988Publication History Published online1 May...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTConformational characterization of glycine residues incorporated into some homopolypeptides by solid-state carbon-13 NMR spectroscopyShinji Ando, Takeshi Yamanobe, Isao Akira Shoji, Takuo Ozaki, Ryoko Tabeta, and Hazime SaitoCite this: J. Am. Chem. Soc. 1985, 107, 25, 7648–7652Publication Date (Print):December 1, 1985Publication History Published online1 May 2002Published inissue 1 December...

Abstract Summary: The phase development mechanism during drawing from a highly entangled melt of ultra‐high‐molecular‐weight polyethylene is analyzed by simultaneous measurements in situ X‐ray diffraction using synchrotron radiation and stress/strain behavior. curve exhibits plateau region at the initial stage draw, no crystalline reflections appear on series patterns. However, as sample draw proceeds above critical strain, metastable hexagonal reflection appears becomes predominant, where...

Abstract Novel tetraalkoxyphenanthrene‐fused dehydro[12]‐, [18]‐, and [24]annulenes 1 – 3 were synthesized by using Cu‐mediated or Pd‐catalyzed oxidative macrocyclization reactions as key steps, their electronic, optical, electrochemical properties have been investigated in detail. X‐ray crystallographic analysis of a single crystal demonstrated that the molecules arranged longitudinally slipped π‐stacked fashion to form 1D column. H NMR UV/Vis spectroscopic cyclic voltammetric conjugation...

Abstract Crystalline homopolymers, including polyethylene (PE), which has the simplest architecture, form a nanometer‐sized combination of crystalline and amorphous components, but their arrangement control, similar to self‐assembled phase‐separation block‐copolymers, is usually difficult. However, molecular entanglements trapped between components homopolymers coincide with segmental linking points on interfaces microphase separation for block copolymers. Nanowrinkled PE membranes are...

Ultrahigh molecular weight polyethylene (UHMW-PE) films having different weights (MWs) were melt-drawn at 150 °C. The stress-strain curve for higher-MW film exhibits higher stress on the characteristic plateau region and a subsequent steeper increase of due to strain hardening. Structural changes during such melt-drawing analyzed using in situ wide-angle X-ray diffraction measurements. Hexagonal crystallization occurs beginning region, independent sample MW. Once this hexagonal reflection...

Changes in the crystalline structure during heating of melt-drawn ultrahigh molecular weight polyethylenes (UHMW-PEs) having different characteristics were analyzed by situ wide-angle X-ray diffraction measurements. A phase transition from orthorhombic into hexagonal was observed for all samples, but perfection enhanced and possible temperature window greater sample containing only a higher component. In contrast, an increase retractive stress confirmed lower component, reflecting melting...

Abstract A novel in situ measurement system for evaluating molecular mobility during uniaxial drawing of polymeric materials was established by introducing and stress‐detecting devices into a 1 H pulse nuclear magnetic resonance spectrometer. In this study, we analyze the changes motion amorphous chains melt‐drawing ultra‐high weight polyethylenes (UHMW‐PEs) with different distributions. initial stage drawing, three‐component resolution possible relaxation decay curve, which includes...

The macrotribological behavior observed when a Si3N4 ball of friction tester slid on polystyrene (PS) surface was compared with the nanotribological tip scanning force microscope (SFM) same surface. macro- and nanofriction forces were measured by conventional ball-on-disk type SFM, respectively, as function applied load. morphological changes rubbed PS surfaces also characterized optical microscopy or SFM observations. Surface plastic deformation always occurred under both tribological...

Solid-echo 1H NMR relaxation was analyzed for ultrahigh molecular weight polyethylene reactor powders. Their high crystallinities reveal the characteristics of crystalline free induction decay (FID). We propose here a very simple but appropriate fitting function component: combination Weibullian and sine functions. The applicability this tested series samples having much higher crystallinity over 90%, which achieved by fuming nitric acid etching at room temperature period 1 year. typical...