In-situ analysis of fiber structure development for isotactic polypropylene
نویسندگان
چکیده
منابع مشابه
Structure and molecular mobility of nascent isotactic polypropylene powders
The detailed structure and molecular mobility of nascent isotactic polypropylene (iPP) powder was investigated using differential scanning calorimetry, transmission electron microscopy (TEM) and nuclear magnetic resonance (NMR). The crystallinity of the nascent iPP powder is approximately 33%, which is much lower than that of melt-quenched or isothermally crystallized iPP. Peaks from the variab...
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A filament stretching extensional rheometer with a custom-built oven was used to investigate the effect of uniaxial flow on the crystallization of polypropylene. Prior to stretching, samples were heated to a temperature well above the melt temperature to erase their thermal and mechanical histories and the Janeschitz-Kriegl protocol was applied. The samples were stretched at extension rates in ...
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Dispersions of isotactic polypropylene (PP) particles in polystyrene (PS) were produced by interfacially driven breakup of nanolayers in multilayered systems that were fabricated by means of layer-multiplying coextrusion. The droplet size was controlled by the individual PP layer thickness ranging from 12 to 200 nm. In addition, PP was melt blended with PS to produce PP droplets larger than tho...
متن کاملA first principles investigation of isotactic polypropylene
Bulk isotactic polypropylene in the a form was studied using density functional theory-based computations. The computed physical structure of this system is in excellent agreement with available experimental data. The electronic band structure, ionization potential, and electron affinity were also determined. The impact of various types of chemical imperfections (including double bond, hydroxyl...
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In this research, a Ziegler–Natta catalyst intercalated MoS2 was synthesized through the intercalation of a Grignard reagent into MoS2 galleries, followed by the anchoring of TiCl4. During propylene polymerization, the intercalated MoS2 exfoliated in situ to form PP/exfoliated MoS2 (EMoS2) nanocomposites. The isotactic index values of the resultant PP/EMoS2 nanocomposites were as high as 99%, v...
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ژورنال
عنوان ژورنال: Polymer
سال: 2011
ISSN: 0032-3861
DOI: 10.1016/j.polymer.2011.03.005