Block-copoly(oxypropylene/oxyethylene/oxypropylene)s, with central-block lengths of 39 and 75 oxyethylene units and end-block lengths in the range 1 to 13 oxypropylene units, were investigated in their solid states by small-angle X-ray diffraction and low-frequency Raman spectroscopy, supplemented by differential scanning calorimetry. Low-frequency Raman transitions were assigned to longitudinal modes (LAM) of either unfolded or once-folded chains. The solid state comprised stacked monolayer lamellae in which the chains were usually tilted with respect to the lamellar end plane.
Low‐Frequency Raman spectra of odd α,ω‐dibromo‐ and α,ω‐dihydroxy‐n‐alkanes were recorded. The longitudinal acoustic mode (LAM‐1) frequencies were assigned by references to the published results for n‐alkanes and even α,ω‐disubstituted n‐alkanes and also by taking account of the effects of end intermolecular forces and end‐group masses by use of the chain model of Minoni and Zerbi.
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