Chain-orientational disorder

Snetivy D and Vancso G J 1994 Atomic force microscopy of polymer crystals 7. Chain packing, disorder and imaging of methyl groups in oriented isotactic polypropylene Po/yme/ 35 461... 

FK5.6.I9 Schematic representation of the structural formation and order-disorder transition for photoactive LBK showing (A) the compressed monolayer on the water surface with densely packed chromophore side chains oriented into the gas phase and the polymer backbone facing the water surface, and (B) LBK transfer from the water to a solid support, resulting in well-ordered smetic-tike (bilayered) multilayer assemblies. (C) After phcnoinduced trars to cts isomerization, a largely disordered struaure is obtained and the layered structure is completely lost (reproduced from reference 72 with permission from Wifey-VCH). 

M. Sprik, U. Roethlisberger, and M. Klein,/. Rhys. Chem. B, 101,2745 (1997). Structure of Solid Poly(tetrafluoroethylene) A Computer Simulation Study of Chain Orientational, Translational, and Conformational Disorder. 

Analysis of the TBPA-Ti complex (39,40) indicates that the binding site for the hormone is located deep inside the channel. The hormone makes extensive interactions with the protein side chains that project into the channel. The 4 -hydroxyl of Ti interacts with a patch of hydroxy-amino acids of the protein while each of the iodines makes contact with a number of hydro-phobic protein residues. The T amino acid side chain functional groups are in appropriate positions to interact with glutamic acid and lysine residues. Thus, this channel provides a favorable environment for each of the characteristic substituents of the thyroid hormone (40). However, because of the Ti orientation disorder in the protein complex, this structural model is not a sensitive measure of the observed correlations between diphenyl ether conformations and binding affinity data. 

A consideration of the paracrystalline distortions, primarily the limited lateral correlations of axial chain coordinates ( chain shift disorder ), is found in the paper by Kawaguchi and Petermann [174]. According to the analysis of their electron diffraction patterns of flow-oriented PPP films, the diffraction on the third and higher layer lines is essentially single-chain diffraction. Although indications for an off-meridional position of the (002) reflection are found in some patterns, the authors favour the orthorhombic unit cell. 

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