Results 81 to 90 of about 107,857,992 (124)

Zur Toxikologie von Polybuten-(1)

F�hner-Weilands Sammlung von Vergiftungsf�llen Archiv f�r Toxikologie, 1968
Unter den Bedingungen eines halbjahrigen Futterversuchs (1% und 10% Gehalt) an Ratten fand sich kein Anhalt fur eine gesundheitliche Bedenklichkeit des Kunststoffs Polybuten-(1).
Gerhard Bornmann, Arnold Loeser
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Growth morphology of isotactic polybutene-1

European Polymer Journal, 1973
Abstract Isotactic polybutene-1 has been crystallized from solution by the film formation method. Well-defined single crystals have been grown from solutions of the polymer in amyl acetate and its mixtures with n-butanol in all the three modifications by varying the concentration and crystallization temperature.
K.S. Sastry, R.D. Patel
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Solution history effects in polybutene-1

Journal of Macromolecular Science, Part B, 1984
Abstract The crystal structure and helical conformation of polybutene-1 crystallized from dilute solution is shown to be a function of the crystal structure before dissolution, the maximum temperature in solution attained before cooling to the crystallization temperature, and the time at that maximum temperature.
K. W. Chau, P. H. Geil
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Differential thermal analysis of polybutene‐1

Journal of Polymer Science Part C: Polymer Symposia, 1964
AbstractThe three polymorphic forms of polybutone‐1 may be easily characterized by DTA: Form I has a DTA peak near 132°C; Form II has a peak near 118°C; and Form III has doublet peaks at 104° and 118°C. The kinetics of the room temperature transformation of Form II to Form I have been qualitatively investigated by DTA.
Bert H. Clampitt, Richard H. Hughes
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Multiple phase transitions of polybutene‐1

Journal of Polymer Science Part C: Polymer Symposia, 1966
AbstractMultiple phase transitions of polybutene‐1 in the form III modification have recently been the subject of discussion by a number of authors. The exact nature of the observed phenomena has remained in doubt, leading to the proposal of divergent theories.
C. Geacintov, R. B. Miles, H. J. L. Schuubmans   +2 more
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Annealing of polybutene‐1 single crystals

Journal of Polymer Science Part A-2: Polymer Physics, 1968
AbstractThe effects of thermal treatment in the 70–90°C. region on polybutene‐1 crystals, prepared by precipitation from dilute pentyl acetate solutions and with lath, hexagonal, and square morphologies, have been studied by using electron microscopy.
A. E. Woodward, D. R. Morrow
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Infrared characterization of polymorphism in polybutene‐1

Journal of Polymer Science Part A-2: Polymer Physics, 1966
AbstractThe transformations of the polymorphic forms of polybutene‐1 (I,II,III) were studied by infrared spectroscopy. Attenuated total reflectance spectra demonstrate that the II → I transformation occurs initially and most rapidly on the film surfaces. Electron irradiation experiments showed the II → I conversion can be suppressed by irradiation. The
J. P. Luongo, R. Salovey
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Preparation of high isotactic polybutene-1

Journal of Applied Polymer Science, 2000
Polymerization of butene-1 (B-1) was carried out with a PP-TiCl3/Et2AlCl/methyl methacrylate (MMA) catalyst system in n-heptane. The influence of temperature, pressure, time and H2 on molecular weight, isotacticity, and catalytic activity were studied by viscometry, solubility in boiling diethyl ether, and measuring the polymer produced, respectively ...
S. Abedi, N. Sharifi-Sanjani
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Time dependent crystallinity of polybutene‐1

Polymer Engineering & Science, 1966
AbstractIsotactic Polybutene‐1 can exist in 4 different crystalline phases of varying stability of which two are of greatest importance because they are involved in solidification from the melt initially, the melt cools into an unstable crystalline phase which gradually and spontaneously transforms into a stable, stronger, stiffer, more crystalline ...
S. Y. Choi, J. P. Rakus, J. L. O'Toole
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Isotactic Polybutene-1 Single Crystals: Morphology

Journal of Applied Physics, 1964
Three crystalline modifications of isotactic polybutene-1 have been obtained from dilute solution in a variety of habits. These three crystalline modifications are: (a) tetragonal, (b) ``untwinned'' hexagonal, and (c) orthorhombic. The structure of the orthorhombic polymorph has not previously been reported.
V. F. Holland, Robert L. Miller
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