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Influence of the quenching temperature on the crystallization of the trans-planar mesomorphic form of syndiotactic polypropylene

✍ Scribed by Claudio De Rosa; Odda Ruiz de Ballesteros; Michele Santoro; Finizia Auriemma


Publisher
Elsevier Science
Year
2003
Tongue
English
Weight
270 KB
Volume
44
Category
Article
ISSN
0032-3861

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✦ Synopsis


The crystallization from the melt of the trans-planar mesomorphic form of syndiotactic polypropylene is investigated at different quenching temperatures. The formation of the trans-planar mesomorphic form at 25, 0 and 6 8C is followed as a function of the residence time at these temperatures by X-ray diffraction and FTIR spectroscopy. The quenching temperature influences the rate of formation of the mesomorphic form as well as the maximum amount of the obtained mesomorphic form. By increasing the quenching temperature, in the examined range between 25 and ΓΎ6 8C, an increase in the rate of formation of the mesomorphic form is observed. The maximum amounts of mesomorphic form obtained at 6 and 25 8C are lower than the amount achieved at 0 8C, which corresponds to nearly 100% of the total crystalline phase.


πŸ“œ SIMILAR VOLUMES


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