Die Makromolekulare Chemie · 1967 · 75 citations · 7 references
Natural SciencesChemistryMaterials ScienceCrystal StructureOrganic ChemistryPolymer ChemistryConformational AnalysisMacromolecular StructurePolymer Chain ConformationPolymer CharacterizationPolymer ConformationPolymer StructureChainsInfrared Absorption SpectraInfrared Absorption SpectroscopyMolecular Conformation AnalysisPolymer Crystal StructureUnit Cell DeterminationUnit Cell GeometryUnit Cell Parameters
Abstract The structure of polyoxacyclobutane has been studied by x‐ray diffraction and infrared absorption methods, and three crystal modifications have been found. The molecular conformation of modification I is essentially planar zigzag, fiber period being 4.80 Å. Modification II is trigonal, R 3 c − C , a = 14.13 Å and c (fiber axis) = 8.41 Å; nine molecular chains of a T 3 GT 3 Ḡ type pass through a unit cell. Modification III is orthorhombic, C 222 1 − D , a = 9.23 Å, b = 4.82 Å, and c (fiber axis) = 7.21 Å; two molecular chains of a (T 2 G 2 ) 2 type pass through the center and the corner of a unit cell. The transitions among, these three modifications were studied and discussed. Modification I is stable only in the presence of water. Modification III is the most stable form, and this is consistent with the antiparallel arrangement of the strong dipole‐moments of the COC groups. Modification II is stable only as oriented samples.
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Molecular configuration of polyoxymethylene
Hiroyuki Tadokoro, Takaya Yasumoto, Shunsuke Murahashi et al. · Journal of Polymer Science · 1960 · 164 citations
Kiyohisa Imada, Takaharu Miyakawa, Yôzô Chatani et al. · Die Makromolekulare Chemie · 1965 · 110 citations