Cross-polarization spectra of xenon adsorbed in a polymer blend with a polypropylene matrix and a polyethylene-propylene copolymer have been obtained. The temperature dependence of the magnetization transfer from 'H to lz9Xe is shown and a 2D 'H-'29Xe correlation spectrum is presented. From the spec
A 129Xe NMR study on an ionomeric polymer blend system
β Scribed by Changlai Yang; Wen-Yang Wen; Alan A. Jones; Paul T. Inglefield
- Book ID
- 104357973
- Publisher
- Elsevier Science
- Year
- 1998
- Tongue
- English
- Weight
- 302 KB
- Volume
- 12
- Category
- Article
- ISSN
- 0926-2040
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β¦ Synopsis
The morphology of an ionomeric polymer blend consisting of an amino-silicone copolymer and zinc neutralized Ε½ . Ε½ . sulfonated polystyrene ZnSPS has been studied using proton spin diffusion and small angle X-ray scattering SAXS . The extent of reaction between the two components in the blend was monitored by 13 C CP MAS spectroscopy. All three types of experiment point to domain sizes in the nanometer range. 129 Xe NMR was used to study exchange by translational diffusion between domains. A single xenon resonance was detected in temperatures ranging from 258C to y908C, and the chemical shift followed a weighted average of the isolated polymer shifts consistent with the small domain sizes. Pulse field gradient 129 Xe NMR was used to determine the effective diffusion constants in the amino silicone starting material and the blend.
Ε½
. The diffusion constant of xenon in poly styrene is known, allowing for comparison of the predictions of effective diffusion constants in the blend based on the values in the constituents of the blend. Simple two-site exchange equations incorrectly predict that diffusion in the blend would be dominated by the constituent with slow diffusion. The blend diffusion constant is close to the value of the amino silicone or the constituent with fast diffusion which is correctly predicted for a rapid exchange solution of the diffusion equation.
π SIMILAR VOLUMES
It is demonstrated that xenon can be used as a tracer for the extraction of structure information in microheterogeneous amorphous polymer systems by means of two-dimensional NMR spectroscopy. lZ9Xe nuclei act as probes for structural heterogeneity. Experiments were performed on two model blends cons