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Kawasaki, Japan

Yamada K.,SunAllomer Ltd. | Kajioka H.,Hiroshima University | Nozaki K.,Yamaguchi University | Toda A.,Hiroshima University
Journal of Macromolecular Science, Part B: Physics | Year: 2011

Isolated single crystals of isotactic polypropylene (iPP) grown from the melt were studied by optical microscopy and atomic force microscopy (AFM). The single crystals had a well-known rectangular shape when crystallized at high temperatures (Tc) above 155°C. The width increased with decreasing Tc, and the shape became hexagonal below 130°C. The single crystals were sectored with thickness difference between them. The growth rate along the a*-axis, Ga*, agreed well with the growth rate of spherulites, as expected. Ga* had two inflection points on the plots against (TδT)-1. The lower temperature inflection corresponds to the regime II-III transition, and the higher temperature one is accompanied by an inflection of the growth rate in the b-axis direction, Gb, which has been measured for the first time. The inflection of Gb at the lower inflection temperature of G a* was much smaller than that of Ga* and may not exist. The crystals are basically surrounded with flat surfaces and no indications of kinetic roughening in the regime III were recognized in the AFM images. The inflections of Ga* and Gb caused a complicated shape change of the aspect ratio, having a minimum at around 135°C. © 2011 Taylor & Francis Group, LLC.


Kajioka H.,Hiroshima University | Yamada K.,SunAllomer Ltd. | Taguchi K.,Hiroshima University | Toda A.,Hiroshima University
Polymer | Year: 2011

Molecular weight dependence of growth and morphology of spherulites of isotactic poly(butene-1), iPB-1, and those of the mixtures with atactic poly(butene-1), aPB-1, were examined by atomic force microscopy (AFM) and polarizing optical microscopy (POM) in order to examine the mechanism of the structural evolution by the branching and re-orientation of lamellar crystals at the growth front. The width of lamellar crystals and the characteristic size of the inner structure of spherulites decreased with increasing molecular weight. The result suggests that the mobility of the melt determines the sizes in spherulites and supports the growth front instability induced by a gradient triggering the branching. The sizes in the mixtures also decreased with increasing weight-averaged molecular weight, M w. The size dependence in low M w region, however, was too strong and that in high M w was too weak in comparison with the predicted dependence for the prepared M w. It has been concluded that the peculiar behaviors should be discussed with effective M w influenced by the occurrence of separation and exclusion of non-crystallizing aPB-1 at the growth front. © 2011 Elsevier Ltd. All rights reserved.


Patent
Sunallomer Ltd. | Date: 2012-07-03

The purpose of the present invention is to produce an alpha-olefin polymer having excellent production stability utilizing a long-lasting high catalytic activity. Provided is a method for producing an alpha-olefin polymer using a catalyst comprising:


A process and apparatus for manufacturing a crystalline resin film or sheet. This manufacturing apparatus includes: an extruder that melts crystalline resin while supplying it; a gear pump that is provided on the downstream side of the extruder; a die which is provided on the downstream side of the gear pump, and which has a slit-shaped aperture; a cooling apparatus which cools film-shaped or sheet-shaped crystalline resin (A) discharged in a melted state from the die to a temperature which is not less than the crystallization temperature but not more than the melting point; and a pair of pinch rolls that press-roll between them the film-shaped or sheet-shaped crystalline resin (B) which has passed through the cooling apparatus (


Patent
Sunallomer Ltd. and Hiroshima University | Date: 2011-10-07

A method for secondary-molding a polymer nano oriented crystal material in accordance with an embodiment of the present invention includes the steps of: heating the polymer nano oriented crystal material so that the polymer nano oriented crystal material changes into a mobile phase or a melt having a dense entanglement network structure; molding the polymer nano oriented crystal material which changed into the mobile phase or the melt including the dense entanglement network in the step; and cooling the polymer nano oriented crystal material, which has undergone the step, until the polymer nano oriented crystal material changes into an ordered phase.

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