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Structure and interactions in homopolymers and blends as studied by the methods of vibrational and nmr spectroscopy
Author(s) -
Dybal Jiîí,
Straka Jaroslav,
Schneider Bohdan,
Schmidt Pavel
Publication year - 1995
Publication title -
macromolecular symposia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.257
H-Index - 76
eISSN - 1521-3900
pISSN - 1022-1360
DOI - 10.1002/masy.19950940104
Subject(s) - materials science , crystallinity , polymer , polymer chemistry , polystyrene , raman spectroscopy , amorphous solid , polymer blend , methyl methacrylate , intermolecular force , relaxation (psychology) , chemical engineering , copolymer , crystallography , molecule , organic chemistry , chemistry , composite material , psychology , social psychology , physics , optics , engineering
The combination of IR, Raman and NMR spectroscopy was used in the study of the blends of semicrystalline and amorphous polymers with considerably different strength of intermolecular interactions: poly(ϵ‐caprolactam)/polystyrene (PCL/PS), poly(ethylene oxide)/poly(methyl methacrylate) (PEO/PMMA) and poly(N‐methyllaurolactam)/poly(4‐vinylphenol) (PNMLL/PVPh). In the vibrational and NMR spectra of the blends composed of non‐interacting polymers (PCL/PS) and weakly interacting polymers (PEO/PMMA), no band changes were observed which would indicate changes of the conformational structures. 1 H NMR relaxation of the PCL and PS components in the blends is the same as in the respective homopolymers similarly treated. In the blends of weakly interacting polymers (PEO/PMMA), the crystallinity of PEO is influenced by the presence of PMMA and is negligible in the blends with less than 30 wt.‐% of PEO. The rotating‐frame spin‐lattice relaxation time for protons T H 1p of PMMA indicates close contact of the PMMA and PEO chains. In the blends PNMLL/PVPh with strong hydrogen‐bonding interactions, both components are intimately mixed on a scale of 3–4 nm and significant shifts of some bands both in vibrational and in NMR spectra reveal changes of structure.