Results 141 to 150 of about 827 (173)

Deformation of polybutene-1 crystal aggregates

Journal of Macromolecular Science, Part B, 1970
Abstract The plastic deformation of polybutene-1 crystals on a uniaxially drawn substrate has been studied using an electron microscope. Crystals with hexagonal morphology and crystal structure, with orthorhombic structure and with square morphology were investigated.
D. R. Morrow, A. E. Woodward
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Phase Transitions in Isotactic Polybutene-1

Journal of Macromolecular Science, Part B, 2019
AbstractThe possibilities to influence the 4 major phase transitions of isotactic polybutene – 1 (iPB-1) and their transformation rate are described.
Kaszonyiová, Martina, Rybnikář, František, Geil, Phillip H.   +2 more
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Crystallization and Transformation of Polybutene‐1

Journal of Macromolecular Science, Part B, 2004
Abstract The isothermal crystallization and phase II → I transformation of bulk polybutene‐1 at various temperatures have been characterized by x‐ray diffraction. The crystallization rate can be increased or decreased by the addition of various solids, with sodium salicylate and talc, e.g., increasing the rate by >100% and, unexpectedly, decreasing the
M. Kaszonyiova, F. Rybnikar, P. H. Geil
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Annealing Behavior of Isotactic Polybutene-1

Journal of Macromolecular Science: Part A - Chemistry, 1987
The annealing behavior of isotactic polybutene-1 (PB-1) has been studied by differential scanning calorimetry and wide-angle x-ray diffraction. On annealing at 110°C, PB-1 yields thick crystals melting at -140°C which are mainly of Form I. An increase in the heat of fusion (ΔHf) and crystallinity is found for annealing times up to 12 h at 110°C; at ...
Kishore, K, Vasanthakumari, R
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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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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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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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Crystallization of forms I′ and form II of polybutene-1 in stretched polypropylene/polybutene-1 blends

Polymer, 2019
Abstract In this work, the effects of orientated crystal morphology of polypropylene (PP) induced by tensile stretching on the subsequent crystallization behavior of polybutene-1 (PB-1) in the incompatible PP/PB-1 (50/50) blends were studied. When the PP/PB-1 blends were stretched at a temperature above melting temperature (Tm) of PB-1 but below the ...
Yao Xu, Yaping Ma, Chenguang Liu, Yongfeng Men, Aihua He   +4 more
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Local deformation in stretched polybutene‐1 spherulites

Journal of Polymer Science Part A-2: Polymer Physics, 1970
AbstractThe orientation of crystals in spherulites of modifications I and II of polybutene‐1 was studied by micro‐x‐ray diffraction. Changes in such micro‐x‐ray diffraction patterns were measured in various regions of the spherulites as a function of strain and time. The relationship between micro‐x‐ray diffraction from parts of spherulites and macro‐x‐
R. Y. Yee, R. S. Stein
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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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