Photochemical Reactions of Organometallic Complexes Impregnated into Polymers: Speciation, Isomerization, and Hydrogenation of Residual Alkene Moieties in Polyethylene

Autor:	Martyn Poliakoff, Matthew J. Clarke, and Steven M. Howdle, Andrew I. Cooper
Rok vydání:	2000
Předmět:	chemistry.chemical_classification Degree of unsaturation Tungsten hexacarbonyl Supercritical carbon dioxide Photoisomerization Alkene General Chemistry Photochemistry Biochemistry Catalysis Iron pentacarbonyl chemistry.chemical_compound Colloid and Surface Chemistry chemistry Molecule Isomerization
Zdroj:	Journal of the American Chemical Society. 122:2523-2531
ISSN:	1520-5126 0002-7863
DOI:	10.1021/ja9919276
Popis:	Tungsten hexacarbonyl, W(CO)6, and iron pentacarbonyl, Fe(CO)5, were impregnated into four different types of polyethylene (PE) using either supercritical carbon dioxide (scCO2) or conventional solvents (n-heptane and carbon tetrachloride). All of the PE samples were known to have some residual alkene unsaturation in the polymer chain, with different relative amounts of vinyl (terminal), pendant, and trans-internal unsaturation. W(CO)6 was found to react photochemically with residual alkene bonds in the impregnated PE films, and to form polymer-bound species of the type W(CO)5(η2-alkene)PE. Extended photolysis led to isomerization of the alkene moieties which was detected by changes in the FTIR spectra of the polymer-bound organometallic. Speciation of the alkene groups both before and after photoisomerization was achieved by use of a probe molecule, (η5-C5H5)Mn(CO)3 (see: Clarke, M. J.; Howdle, S. M.; Jobling, M.; Poliakoff, M. J. Am. Chem. Soc. 1994, 116, 8621−28). In each case, the isomerization react...
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::0f0e28a325a6d6f6b0a7f296d4dbe0e2 https://doi.org/10.1021/ja9919276 Zobrazit plný text záznamu