Structural study of syndiotactic polystyrene: 1. Polymorphism

Chatani, Yôzô; Shimane, Yukio; Inoue, Yuko; Inagaki, Toru; Ishioka, Tsutomu; Ijitsu, Toshikazu; Yukinari, Toshimitsu

doi:10.1016/0032-3861(92)90723-a

Cited by 208 publications

(178 citation statements)

References 9 publications

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“…In the sPS/p-xylene system, the peak appears at almost the same angle as in the sPS/toluene system. 23,24 This supports the previous findings that either methyl group of p-xylene exists at the same site in the cavity as that of the methyl group of toluene in the sPS/toluene system. In the sPS/m-xylene system, however, the reflection was observed at smaller 2θ angle, indicating that the distance of the helical sPS chains in the sPS/m-xylene system is longer than that of the sPS/p-xylene system.…”

Section: Resultssupporting

confidence: 89%

“…In this equation, one guest molecule was assumed present in the cavity formed by the four sPS monomer units in the δ-form complex, as also in previous reports on sPS/toluene system. 23,24 p-And m-xylene isomers in these systems were considered completely incorporated into the δ- form complex. χ c δ were 70 and 65% for sPS/p-xylene and sPS/m-xylene systems, respectively, approximately agreeing with previous reports.…”

Section: Resultsmentioning

confidence: 99%

“…There are mainly five diffraction peaks typical of the δ-form complex of sPS. 23,24 The diffraction peak around 2θ = 8 • was assigned to the (0,1,0) plane. This corresponds to the distance between two adjacent sPS helical chains along the b-axis of the unit cell of the δ-form complex.…”

Section: Resultsmentioning

confidence: 99%

“…23,24,[35][36][37] Figure 4 indicates a schematic representation of the δ-form complex model in which the two adjacent right-handed (-TTGG-) 2 , left-handed (-TTGG-) 2 helical sPS chains accommodated one symbolized guest molecule.…”

Section: Resultsmentioning

confidence: 99%

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Study on δ-Form Complex in Syndiotactic Polystyrene-Organic Molecules System III. Fine Structures of Complexes with Xylene Isomers by Means of High-Resolution Solid-State 13C NMR Spectroscopy

Yamamoto

Kishi

Amutharani

et al. 2003

Polym J

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ABSTRACT:Syndiotactic polystyrene (sPS) is known to form a clathrate compound with p-xylene and m-xylene, called δ-form complex. In this study, the structures of the sPS/p-xylene and sPS/m-xylene systems were investigated by high-resolution solid-state 13 C nuclear magnetic resonance ( 13 C NMR) and X-ray diffraction. From the Miller indices of the (0,1,0) reflection, it was confirmed that the distance between sPS helical chains in the m-xylene system was longer than that of the p-xylene system. It was concluded that the location of one methyl group of m-xylene in the sPS δ-form complex coincided with that of one methyl group of p-xylene, because the 13 C NMR chemical shift and spin-lattice relaxation time of the methyl carbon of p-xylene were similar to those of one methyl carbon of m-xylene in the sPS δ-form complex. The meta substituted another methyl group of m-xylene showed a low-field chemical shift, indicating it close to the two phenyl groups of sPS chains in the δ-form complex.

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Section: Resultssupporting

confidence: 89%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

See 2 more Smart Citations

Study on δ-Form Complex in Syndiotactic Polystyrene-Organic Molecules System III. Fine Structures of Complexes with Xylene Isomers by Means of High-Resolution Solid-State 13C NMR Spectroscopy

Yamamoto

Kishi

Amutharani

et al. 2003

Polym J

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“…sPS/ TEGDME cocrystal films were prepared by soaking the sPS/ chloroform films to liquid TEGDME for one day and then keeping them in a vacuum oven at 40°C for an hour. The sample thus prepared forms a δ monoclinic clathrate structure, 12 where TEGDME molecules are encapsulated in the cavities in the crystalline region consisting of sPS helices. 13 All simultaneous SANS/FTIR experiments were carried out by using the above-mentioned experimental setup installed at KWS2 of the Jülich Centre for Neutron Science (JCNS) outstation at Heinz Maier-Leibnitz Center (MLZ) in Garching, Germany.…”

mentioning

confidence: 99%

Development of a Simultaneous SANS/FTIR Measuring System

et al. 2015

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A novel method for the simultaneous measurement of smallangle neutron scattering and Fourier transform infrared spectroscopy (SANS/FTIR) has been developed. The method was realized by building a device consisting of a portable FTIR spectrometer and an optical system that allows both a neutron beam and an infrared beam to pass through a sample coaxially. The device was installed on a small-angle neutron diffractometer, KWS2 of the Jülich Centre for Neutron Science (JCNS) outstation at Heinz Maier-Leibnitz Center (MLZ) in Garching, Germany. In order to check the performance of this measuring system, the structural changes in a cocrystal of syndiotactic polystyrene with triethylene glycol dimethyl ether, were followed during the course of heating.Small-angle neutron scattering (SANS) is a powerful and convenient method to investigate the higher-order structure of static polymer systems. Owing to technological developments in instruments such as detectors and neutron guides, SANS has extended its presence, even to research concerning timedependent structural evolution.The scattering pattern of SANS is determined by the scattering length density (SLD) profile of the object under study, and therefore, it is of great difficulty to derive the sole solution for the arrangement of constituent components from the scattering pattern of SANS. Accordingly, if a system of interest is a multicomponent one, the interpretation of the time-dependent changes in SANS profile is not easy. There are usually several alternatives to explain the variations in the SANS profile, and it is laborious to select an option from them. 1,2 It is desirable to obtain two or more different kinds of structural information simultaneously from the same sample, which would drastically reduce ambiguities in interpretation. Vibrational spectroscopy has been employed as a complementary tool to X-ray and neutron diffractometry for investigating the structure of polymer systems. Simultaneous analyzes by X-ray scattering and Fourier transform infrared spectroscopy (FTIR) have been developed so far. 36 We expect that the combination of SANS with FTIR would also produce a fruitful methodology for such a simultaneous measurement system. Owing to a high-throughput optical system, a highly sensitive detector, and advanced hardware and software design, it is easy to follow the time-evolution of infrared spectra with a compact FTIR spectrometer. 7,8 Such flexibility of FTIR has been employed also for simultaneous measurement with differential scanning calorimetry (DSC). 9,10 In this study, we tried to establish the simultaneous SANS/ FTIR measurement protocol. For this purpose, a device consisting of a portable FTIR spectrometer and an optical system, which allows a sample to be irradiated with neutron and infrared beams simultaneously, was developed and installed on a smallangle neutron diffractometer. In the proof-of-concept experiment described here, we followed the structural changes on heating a crystalline complex system of syndiotactic polystyrene (sPS) with...

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Regeneration of nanoporous crystalline syndiotactic polystyrene by supercritical CO2

Reverchon

Guerra

Venditto

1999

J. Appl. Polym. Sci.

102

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ABSTRACT:Guest desorption procedures for s-PS clathrate samples, leading to formation and regeneration of the nanoporous ␦ phase, are compared. An extraction procedure, based on supercritical carbon dioxide, allows an easy and fast recovery of the guest molecules operating under relatively mild conditions (90 -200 bar, 40°C) and generates a completely empty ␦ form, also starting from the most stable s-PS clathrate forms. In agreement with a previously proposed crystal structure of the nanoporous ␦ form, X-ray diffraction patterns of ␦ form powders obtained by this procedure do not show the peak, which is reduced but still apparent in samples extracted with previous procedures based on boiling solvents.

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Structural study of syndiotactic polystyrene: 1. Polymorphism

Cited by 208 publications

References 9 publications

Study on δ-Form Complex in Syndiotactic Polystyrene-Organic Molecules System III. Fine Structures of Complexes with Xylene Isomers by Means of High-Resolution Solid-State 13C NMR Spectroscopy

Study on δ-Form Complex in Syndiotactic Polystyrene-Organic Molecules System III. Fine Structures of Complexes with Xylene Isomers by Means of High-Resolution Solid-State 13C NMR Spectroscopy

Development of a Simultaneous SANS/FTIR Measuring System

Regeneration of nanoporous crystalline syndiotactic polystyrene by supercritical CO2

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