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M.J. Kunz, W.H. Binder:
"NMR-studies on hydrogen-bonded supramolecular polyetherketones";
Poster: 5^th International Conference in Advanced Polymers via Macromolecular Engineering APME-5' 2003, Montreal, Canada; 21.06.2003 - 26.06.2003; in: "Advanced Polymers via Macromolecular Engineering", (2003).

Polymer chemistry has been subjected to large changes during the past decades, substituting "conventional" covalently linked polymers and block-copolymers by new supramolecular non-covalently-linked polymer systems. Hydrogen bonds, dipol-dipol interactions, p-p stacking and charge-charge interactions can be used to generate chains with tuneable molecular weights as well as dendritic architecture and weakly crosslinked networks in solution. Therefrom new materials with tuneable properties such as modulative mechanical and rheological properties as well as tuneable and switchable nanostructures can be designed. We report the formation of supramolecular polymers derived from dodecyl-(a-??-bis-(5-methyl-1,3-pyrimidine-2,4-dione) and the complementary 2,4-diamino-1,3,5-triazine-telechelic polyetherketone (triazine-PEK). Both structures interact by complementing hydrogen bonding units present at their respective chain ends reminiscent of the triple hydrogen bonding in DNA. The structure of the triazine PEKs is proven by 13C-NMR-spectroscopy and MALDI-spectroscopy. When the triazine PEKs are mixed as a 1:1 complex in solution with dodecyl-(a-??-bis-(5-methyl-1,3-pyrimidine-2,4-dione), the short triazine-PEK’s show a temperature dependent association behavior visible by dynamic NMR-spectroscopy. A strong shift of the central NH-bond of the dodecyl-(a-??-bis-(5-methyl-1,3-pyrimidine-2,4-dione) from 8.8 ppm (solution in CDCl3) torwards 12.4 ppm in the 1:1 complex can be seen. Additional proof of the formation of a supramolecular, hydrogen bonded network is derived from solid state NMR-spectroscopy, thermal-, and rheological investigations. Polymer chemistry has been subjected to large changes during the past decades, substituting "conventional" covalently linked polymers and block-copolymers by new supramolecular non-covalently-linked polymer systems. Hydrogen bonds, dipol-dipol interactions, p-p stacking and charge-charge interactions can be used to generate chains with tuneable molecular weights as well as dendritic architecture and weakly crosslinked networks in solution. Therefrom new materials with tuneable properties such as modulative mechanical and rheological properties as well as tuneable and switchable nanostructures can be designed. We report the formation of supramolecular polymers derived from dodecyl-(a-??-bis-(5-methyl-1,3-pyrimidine-2,4-dione) and the complementary 2,4-diamino-1,3,5-triazine-telechelic polyetherketone (triazine-PEK). Both structures interact by complementing hydrogen bonding units present at their respective chain ends reminiscent of the triple hydrogen bonding in DNA. The structure of the triazine PEKs is proven by 13C-NMR-spectroscopy and MALDI-spectroscopy. When the triazine PEKs are mixed as a 1:1 complex in solution with dodecyl-(a-??-bis-(5-methyl-1,3-pyrimidine-2,4-dione), the short triazine-PEK’s show a temperature dependent association behavior visible by dynamic NMR-spectroscopy. A strong shift of the central NH-bond of the dodecyl-(a-??-bis-(5-methyl-1,3-pyrimidine-2,4-dione) from 8.8 ppm (solution in CDCl3) torwards 12.4 ppm in the 1:1 complex can be seen. Additional proof of the formation of a supramolecular, hydrogen bonded network is derived from solid state NMR-spectroscopy, thermal-, and rheological investigations.

http://aleph.ub.tuwien.ac.at/F?base=tuw01&func=find-c&ccl_term=AC04405130