The crystal structure of isotactic polyepichlorohydrin

Perego, G.; Cesari, M.

doi:10.1002/macp.1970.021330111

Cited by 10 publications

(1 citation statement)

References 2 publications

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“…Characteristic selected-area diffraction patterns are shown in Figure , where the crystallographic axes a and b are correctly oriented to correspond to the crystal axes. Both are composed exclusively of ( hk 0) reflections, their spacing agreeing consistently within experimental error with corresponding values obtained previously in X-ray diffraction studies of racemic PECH and PPrO . This result is in accord with an orthogonal orientation of the chain c axes as is reasonable in terms of the orthorhombic symmetry of unit cells (see Table ).…”

Section: Resultssupporting

confidence: 90%

Optically Active Polyethers. 3. On the Relationship between Main-Chain Chirality and the Lamellar Morphology of Solution-Grown Single Crystals

et al. 1999

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The morphology of chiral (R)- and (S)-poly(epichlorohydrin) (PECH) single crystals grown from solution was studied to obtain insight into the mechanism by which the chiral character of the main chain can be transmitted to higher organizational levels, such as the lamellar twisting orientation in banded spherulites. Poor solvents were selected so that the crystallization from solution occurred at high temperatures, where the resulting lamellar habits simulate most closely those obtained in crystallization from the melt. Interestingly, the TEM examination of folded-chain single-crystal lamellae showed no morphological evidence that could be related to the chiral character, R or S, of the polyenantiomer. In addition, it was established that the handedness (or sense) of screw dislocations in these lamellae is not controlled by the main-chain chirality. This result supports previous evidence which shows that, although the screw dislocations may contribute to the banding through lamellar branching, they appear not to be primary determinants of either the handedness or magnitude of the twist of lamellae in banded spherulites. Similar morphology patterns were obtained for lamellar single crystals of chiral (R)- and (S)-poly(propylene oxide) and of the optically active biopolyester, (R)-poly(3-hydroxyvalerate), supporting the generality of these features. In searching further for chiral effects, the examination of lamellar morphology in large PECH aggregates, e.g., highly dendritic crystals and hedrites, grown from solution indicated that some of the lamellae are nonplanar while in solution. Some considerations pertaining to the factors that may contribute to the nonplanar habits observed in the morphology of these large aggregates are discussed as well.

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Section: Resultssupporting

confidence: 90%

Optically Active Polyethers. 3. On the Relationship between Main-Chain Chirality and the Lamellar Morphology of Solution-Grown Single Crystals

et al. 1999

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Crystallographic Data and Melting Points for Various Polymers

Miller

1999

The Wiley Database of Polymer Properties

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An analysis of structural changes in the process of thermal crystallization of poly(epichlorohydrin) by means of WAXS and microscopic methods

1985

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Act= Polymerica 36 (1905) Nr. 9 483 Strukturelle Besonderheiten und einige physikalisch-chemische Eigenschaften von aus nichtwaprigen Lcisungen erhaltenen Mischungen oon Cellulose und synthetischen Polymeren. 2. Hochauflcisende 13C-NMR von Mischungen aus Cellulose und synthetischen Polymeren im festen Zustund Mit Hilfe der hochauflosenden 13C-NMR-Spektroskopie wurden Mischungen von Cellulose mit Polymethylmethacrylat, Polyacrylnitril, Polyvinylacetat, Polyvinylalkohol und Polydimethylsiloxan mit unterschiedlicher quantitativer Zusammensetzung untersucht.

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The crystal structure of isotactic polyepichlorohydrin

Cited by 10 publications

References 2 publications

Optically Active Polyethers. 3. On the Relationship between Main-Chain Chirality and the Lamellar Morphology of Solution-Grown Single Crystals

Optically Active Polyethers. 3. On the Relationship between Main-Chain Chirality and the Lamellar Morphology of Solution-Grown Single Crystals

Crystallographic Data and Melting Points for Various Polymers

An analysis of structural changes in the process of thermal crystallization of poly(epichlorohydrin) by means of WAXS and microscopic methods

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