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Journal ArticleDOI

Morphology and crystal structure of CTFMP and bulk polymerized poly(trimethylene terephthalate)

01 Jul 2001-Polymer (Elsevier)-Vol. 42, Iss: 16, pp 7181-7195
TL;DR: In this article, the triclinic unit cell of polytrimethylene terephthalate (PTT) was determined from electron diffraction patterns and modeling using the Cerius 2 simulation program.
About: This article is published in Polymer.The article was published on 2001-07-01. It has received 52 citations till now. The article focuses on the topics: Triclinic crystal system & Crystal structure.
Citations
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Journal ArticleDOI
TL;DR: In this paper, the properties of polytrimethylene terephthalate (PTT) polymers were investigated and compared with those of poly(butylene tereylphthalate) (PBT), and two commercial PTT polymers and one glass fiber reinforced PTT compound were compared.
Abstract: Poly(trimethylene terephthalate) (PTT) was systematically studied as an engineering thermoplastics material. Crystallization rates, crystalline degrees, and mechanical properties of two commercial PTT polymers and one glass fiber–reinforced PTT compound were investigated and compared with those of poly(butylene terephthalate) (PBT). PTT raw polymers have crystallization temperature (Tc) values around 152°C, and their kneaded polymers show Tc values of about 177°C, about 15°C lower than the values of PBT polymers used in this study. From the exothermic heat values of DSC measurements, both PTT and PBT show the crystalline degree order greater than 30%. Injection-molded PTT specimens and PBT specimens exhibit crystalline degrees from 18 to 32% and 23.8 to 30%, respectively. PTT polymers show higher tensile and flexural strengths, but lower impact strengths and elongations than those of PBT polymers. The low elongation behavior of PTT does not change with the intrinsic viscosity and the molder temperature. PTT-GF30 promotes better mechanical properties than those of PBT-GF30, close to those of PET-GF30. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1657–1666, 2004

93 citations

Journal ArticleDOI
TL;DR: In this article, the Avrami and Lauritzen-Hoffmann treatments were applied to evaluate kinetic parameters of poly(propylene terephthalate) isothermal crystallization.
Abstract: The kinetics of crystallization of poly(propylene terephthalate) (PPT) sam- ples of different molecular weights were studied under both isothermal and nonisother- mal conditions. The Avrami and Lauritzen-Hoffmann treatments were applied to evaluate kinetic parameters of PPT isothermal crystallization. It was found that crys- tallization is faster for low-molecular-weight samples. The modified Avrami equation, and the combined Avrami-Ozawa method were found to successfully describe the nonisothermal crystallization process. Also, the analysis of Lauritzen-Hoffmmann was tested and it resulted in values close to those obtained with isothermal crystallization data. The nonisothermal kinetic data were corrected for the effect of the temperature lag and shifted alone with the isothermal kinetic data to obtain a single master curve, according to the method of Chan and Isayev, testifying to the consistency between the isothermal and corrected nonisothermal data. A new method for ranking of polymers, referring to the crystallization rates, was also introduced. This involved a new index that combines the maximum crystallization rate observed during cooling with the average crystallization rates over the temperature range of the crystallization peak. Furthermore, the effective energy barrier of the dynamic process was evaluated with the isoconversional methods of Flynn and Friedmann. It was found that the energy barrier is lower for the low-molecular-weight PPT. The effect of the catalyst remnants on the crystallization kinetics was also investigated and it was found that this is significant only for low-molecular-weight samples. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3775-3796, 2004

64 citations

Journal ArticleDOI
01 Jan 2002-Polymer
TL;DR: In this article, a three-phase model consisting of crystalline, mobile amorphous and rigid amomorphous phases (RAP) was used to describe the structural formation of poly(trimethylene terephthalate) (PTT) at various crystallization conditions.

62 citations

Journal ArticleDOI
TL;DR: In this article, a combination of high-temperature AFM and time and temperature-resolved SAXS/WAXS was employed to examine the microstructural evolution during isothermal melt-crystallization and subsequent melting of poly(trimethylene terephthalate).
Abstract: The thermal behavior of semicrystalline polymers constitutes a long-standing problem in polymer crystallization. Although it is widely agreed that the crystal thickness resulting from isothermal crystallization is a sharply selected value, the melting behavior of semicrystalline polymers is very complex. In this work, a combination of high-temperature AFM and time- and temperature-resolved SAXS/WAXS was employed to examine the microstructural evolution during isothermal melt-crystallization and subsequent melting of poly(trimethylene terephthalate). The SAXS data were analyzed in the frame of the generalized paracrystalline lamellar stack model. The crystal thickness remains almost constant and uniform throughout the isothermal crystallization and melting. The crystals squeezed between the thinnest amorphous layers melt first. The reciprocal size of the amorphous regions undergoing transformation scales linearly with temperature. A simple model is proposed, which accounts for this confinement-driven melti...

59 citations

Journal ArticleDOI
01 Aug 2002-Polymer
TL;DR: In this article, the effect of take-up velocity on the structure and properties of as-spun fibers has been characterized through measurements of birefringence, density, wide-angle X-ray scattering, DSC melting behavior, tensile properties and boiling water shrinkage (BWS).

58 citations

References
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Book
01 Jan 1979

400 citations

Journal ArticleDOI
01 Jul 2001-Polymer
TL;DR: In this paper, the crystal structure of polytrimethlene teraphthalate (PTT) has been determined using both electron diffraction (ED) on single crystals and wide angle X-ray diffraction on powder and oriented fibers.

215 citations

Journal ArticleDOI
01 Apr 1979-Polymer
TL;DR: In this article, the crystal structure of poly(trimethylene terephthalate) was determined by a combination of electron diffraction, X-ray diffraction and packing analyses.

160 citations

Journal ArticleDOI
01 May 1979-Polymer
TL;DR: The determination of the crystalline structure of oriented fibres of poly(trimethylene terephthalate) is described in this article, where the unit cell is triclinic with the following parameters: a = 4.6 A, b = 6.2 A, c = 18.3 A, α = 98°, β = 90°, γ = 112°.

142 citations

Journal ArticleDOI
TL;DR: In this article, the use of front-surface specular reflection FT-IR spectroscopy to characterize surface orientation in thick samples of poly(ethylene terephthalate) (PET) has been investigated.
Abstract: The use of front-surface specular reflection FT-IR spectroscopy to characterize surface orientation in thick samples of poly(ethylene terephthalate) (PET) has been investigated. It has been shown that, even for samples whose surface uniformity is less than perfect, absorption index spectra of excellent quality are obtained from the Kramers-Kronig transformation. These spectra provide detailed information, both qualitative and quantitative, on the molecular conformation and orientation of the polymer. Of particular interest are the strongly absorbing bands such as the carbonyl and ester peaks, which are generally saturated in transmission spectra. The reflection technique opens up the possibility of obtaining new information on conformational changes and orientation in PET through a detailed study of these peaks.

98 citations