๐”– Bobbio Scriptorium
โœฆ   LIBER   โœฆ

Two-phase crystallization kinetics of syndiotactic polystyrene

โœ Scribed by Andrea Sorrentino; Roberto Pantani; Giuseppe Titomanlio


Publisher
John Wiley and Sons
Year
2010
Tongue
English
Weight
560 KB
Volume
48
Category
Article
ISSN
0887-6266

No coin nor oath required. For personal study only.

โœฆ Synopsis


Abstract

In this work, a two phase crystallization model based on the extension of the Kolmogoroff approach was proposed and verified by comparison with experimental isothermal and nonisothermal crystallization data of Syndiotactic Polystyrene (sPS) in a very wide range of cooling rates, up to 600 ยฐC/s. To investigate the effects of high cooling rate on the sPS crystalline structure, a homemade apparatus was adopted. The morphology in solid samples was analyzed by densitometry, IR spectroscopy, and Xโ€rays diffraction. The coupling of these techniques allows the determination of the fractions of different crystalline phases. In agreement with meltโ€crystallization studies of sPS proposed by different authors, either ฮฑ and ฮฒ forms could be produced depending on the thermal history of the sample. Results show that the stable ฮฒ form is favored for specimens solidified at higher temperature or under low cooling rates, whereas ฮฑ and mesomorphic forms are favoured at low temperature or high cooling rates. The proposed multiphase crystallization kinetics model successfully described all the range of experimental data. ยฉ 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1757โ€“1766, 2010


๐Ÿ“œ SIMILAR VOLUMES


Cold-crystallization kinetics of syndiot
โœ Hongbin Lu; Steven Nutt ๐Ÿ“‚ Article ๐Ÿ“… 2003 ๐Ÿ› John Wiley and Sons ๐ŸŒ English โš– 110 KB ๐Ÿ‘ 2 views

## Abstract The kinetics of the isothermal and nonisothermal cold crystallization of syndiotactic polystyrene (sโ€PS) were characterized with differential scanning calorimetry. A Johnsonโ€“Mehlโ€“Avrami analysis of the isothermal experiments indicated that the cold crystallization of sโ€PS at a constant

Isothermal and nonisothermal melt-crysta
โœ Qingyong Chen; Yingning Yu; Tianhai Na; Hongfang Zhang; Zhishen Mo ๐Ÿ“‚ Article ๐Ÿ“… 2002 ๐Ÿ› John Wiley and Sons ๐ŸŒ English โš– 214 KB ๐Ÿ‘ 1 views

## Abstract Analyses of the isothermal and nonisothermal melt kinetics for syndiotactic polystyrene have been performed with differential scanning calorimetry, and several kinetic analyses have been used to describe the crystallization process. The regime IIโ†’III transition, at a crystallization tem

Crystallization kinetics of syndiotactic
โœ Miller, Robert L. ;Seeley, Evelyn G. ๐Ÿ“‚ Article ๐Ÿ“… 1982 ๐Ÿ› Wiley (John Wiley & Sons) ๐ŸŒ English โš– 531 KB

## Abstract Meltingโ€point and spherulite growth rate measurements for a sample of syndiotactic polypropylene (__S__ = 0.716 and ฮท = 0.356) were analyzed for the parameters characterizing crystal formation and growth: __T__~__m__~ = 159 ยฑ 2ยฐC, ฯƒ~__e__~ = 47 erg cm ^โˆ’2^, ฯƒ = 4.4 erg cm^โˆ’2^, and __q__