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Solid-state Polymerization (solid-state + polymerization)

Distribution by Scientific Domains
Polymers and Materials Science83%

Selected Abstracts

Solid-state polymerization of melt-spun poly(ethylene terephthalate) fibers and their tensile properties

JOURNAL OF APPLIED POLYMER SCIENCE, Issue 3 2007
Sachiko Nitta
Abstract The production of high modulus and high strength poly(ethylene terephthalate) fibers was examined by using commercially available melt-spun fibers with normal molecular weight (intrinsic viscosity = 0.6 dL/g). First, molecular weight of as-spun fibers was increased up to 2.20 dL/g by a solid-state polymerization, keeping the original shape of as-spun fibers. Second, the polymerized as-spun fibers were drawn by a conventional tensile drawing. The achieved tensile modulus and strength of as-drawn fibers (without heat setting) were 20.0 and 1.1 GPa, respectively. A heat setting was carried out for the as-drawn fibers. Tensile properties of the treated fibers were greatly affected by the condition of the heat setting. This was related to the increase of sample crystallinity and molecular degradation during the treatments. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1791,1797, 2007 [source]

Effect of poly(ethylene glycol) on the solid-state polymerization of poly(ethylene terephthalate)

POLYMER INTERNATIONAL, Issue 3 2006
E Bhoje Gowd
Abstract Poly(ethylene glycol) (PEG) and end-capped poly(ethylene glycol) (poly(ethylene glycol) dimethyl ether (PEGDME)) of number average molecular weight 1000 g mol,1 was melt blended with poly(ethylene terephthalate) (PET) oligomer. NMR, DSC and WAXS techniques characterized the structure and morphology of the blends. Both these samples show reduction in Tg and similar crystallization behavior. Solid-state polymerization (SSP) was performed on these blend samples using Sb2O3 as catalyst under reduced pressure at temperatures below the melting point of the samples. Inherent viscosity data indicate that for the blend sample with PEG there is enhancement of SSP rate, while for the sample with PEGDME the SSP rate is suppressed. NMR data showed that PEG is incorporated into the PET chain, while PEGDME does not react with PET. Copyright © 2005 Society of Chemical Industry [source]

Solid-state polymerization of melt-spun poly(ethylene terephthalate) fibers and their tensile properties

JOURNAL OF APPLIED POLYMER SCIENCE, Issue 3 2007
Sachiko Nitta
Abstract The production of high modulus and high strength poly(ethylene terephthalate) fibers was examined by using commercially available melt-spun fibers with normal molecular weight (intrinsic viscosity = 0.6 dL/g). First, molecular weight of as-spun fibers was increased up to 2.20 dL/g by a solid-state polymerization, keeping the original shape of as-spun fibers. Second, the polymerized as-spun fibers were drawn by a conventional tensile drawing. The achieved tensile modulus and strength of as-drawn fibers (without heat setting) were 20.0 and 1.1 GPa, respectively. A heat setting was carried out for the as-drawn fibers. Tensile properties of the treated fibers were greatly affected by the condition of the heat setting. This was related to the increase of sample crystallinity and molecular degradation during the treatments. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1791,1797, 2007 [source]

Copolymerization of poly(vinyl alcohol)- graft -poly(1,4-dioxan-2-one) with designed molecular structure by a solid-state polymerization method

JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 9 2006
Si-Chong Chen
Abstract Poly(vinyl alcohol)- graft -poly(1,4-dioxan-2-one) (PVA- g -PPDO) with designed molecular structure was synthesized by a solid-state polymerization. The solid-state copolymerization was preceded by a graft copolymerization of PDO initiated with PVA as a multifunctional initiator, and Sn (Oct)2 as a coininitiator/catalyst in a homogeneous molten state. The polymerization temperature was then decreased and the copolymerization was carried out in a solid state. The products prepared by solid-state polymerization were characterized by 1H NMR and DSC, and were compared with those synthesized in the homogeneous molten state. The degree of polymerization (Dp), degree of substitution (Ds), yield and the average molecular weight of the graft copolymer with different molecular structure were calculated from the 1H NMR spectra. The results show that the crystallization process during the solid-state polymerization may suppress the undesirable inter- or intramolecular side reactions, then resulting in a controlled molecular structure of PVA- g -PPDO. The results of DSC measurement show that the molecular structures determine the thermal behavior of the PVA- g -PPDO. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3083,3091, 2006 [source]

Effect of poly(ethylene glycol) on the solid-state polymerization of poly(ethylene terephthalate)

POLYMER INTERNATIONAL, Issue 3 2006
E Bhoje Gowd
Abstract Poly(ethylene glycol) (PEG) and end-capped poly(ethylene glycol) (poly(ethylene glycol) dimethyl ether (PEGDME)) of number average molecular weight 1000 g mol,1 was melt blended with poly(ethylene terephthalate) (PET) oligomer. NMR, DSC and WAXS techniques characterized the structure and morphology of the blends. Both these samples show reduction in Tg and similar crystallization behavior. Solid-state polymerization (SSP) was performed on these blend samples using Sb2O3 as catalyst under reduced pressure at temperatures below the melting point of the samples. Inherent viscosity data indicate that for the blend sample with PEG there is enhancement of SSP rate, while for the sample with PEGDME the SSP rate is suppressed. NMR data showed that PEG is incorporated into the PET chain, while PEGDME does not react with PET. Copyright © 2005 Society of Chemical Industry [source]

State estimation of a solid-state polymerization reactor for PET based on improved SR-UKF

ASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 2 2010
Ji Liu
Abstract A state estimator for the continuous solid-state polymerization (SSP) reactor of polyethylene terephthalate (PET) is designed in this study. Because of its invalidity in the application to some of the practical examples such as SSP processes, the square-root unscented Kalman filter (SR-UKF) algorithm is improved for the state estimation of arbitrary nonlinear systems with linear measurements. Discussions are given on how to avoid the filter invalidation and accumulating additional error. Orthogonal collocation method has been used to spatially discretize the reactor model described by nonlinear partial differential equations. The reactant concentrations on chosen collocation points are reconstructed from the outlet measurements corrupted with a large noise. Furthermore, the error performance of the developed ISR-UKF is investigated under the influence of various initial parameters, inaccurate measurement noise parameters and model mismatch. Simulation results show that this technique can produce fast convergence and good approximations for the state estimation of SSP reactor. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source]