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Nanoheterogeneity in PEO/PMMA blends probed by 129Xe-NMR

✍ Scribed by S. Schantz; W. S. Veeman

Publisher: John Wiley and Sons
Year: 1997
Tongue: English
Weight: 193 KB
Volume: 35
Category: Article
ISSN: 0887-6266
DOI: 10.1002/(sici)1099-0488(19971130)35:16<2681::aid-polb11>3.0.co;2-5

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✦ Synopsis

Xenon has been used as a structural probe of solid poly(ethylene oxide)/ atactic poly(methyl methacrylate) (PEO/PMMA) blends of concentrations 10/90 to 75/25. 129 Xe-NMR spectra at 293 K show significant changes in line width and chemical shift as the blend composition is varied. The 129 Xe spectra are interpreted in terms of exchange between amorphous single-phase PEO and PMMA domains. It is shown that a simple two-site exchange model can be used to calculate spectra which fit the experimental data over the whole concentration range. Xe exchange between blend subregions is demonstrated also by a two-dimensional NMR experiment. The PEO/PMMA results are compared to previously published poly(vinylidene fluoride)/PMMA 129 Xe spectra.

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