- Process for preparing fluorinated alkyl carboxylate esters
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A process for preparing fluorinated alkyl carboxylate esters comprises reaction of a silver carboxylate or silver carboxylate precursor, such as silver (I) iodide with a fluorinated alkyl iodide and a carboxylic acid. Preferably the fluorinated alkyl iodide has the general formula CF3(CF2)nCH2CH2I, wherein n is an integer in the range of from 1 to 29 and the carboxylic acid is acetic acid, acrylic acid or methacrylic acid.
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Page/Page column 5
(2008/06/13)
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- Synthesis and characterization of semifluorinated polymers via group transfer polymerization
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Group transfer polymerization (GTP) was used to prepare semifluorinated polymers based on acrylic and methacrylic monomers. In the first case, electrophilic catalyzed GTP was applied with 1-methoxy-2-methyl-1-trimethylsilyloxy-1-propene (MMTP) as initiator, zinc iodide as catalyst and 1H,1H,2H,2H-perfluorooctyl acrylate as monomer. In this way it has been possible to obtain oligomers. Higher molecular weight polymers were prepared by means of the nucleophilic tetrabutylammonium benzoate as catalyst. With MMTP as initiator, 1H,1H,2H,2H-perfluoroalkyl methacrylates, F(CF2)m(CH2)2OCOC(CH3)=CH2, were polymerized to molecular weights > 4.5 kg mol-1. The polydispersity was found to depend strongly on the length of the perfuoroalkyl side chain, i.e. Mw/Mn decreases with increasing m.
- Krupers, Maarten J.,Moeller, Martin
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p. 119 - 124
(2007/10/03)
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- Synthesis and Mesoscopic Organization of Perfluoroalkyl-Alkylene Methacrylate Monomers
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Alcohols with perfluorinated segments, F(CF2)n-(CH2)m-OH; n = 8, 10, 12; m = 4, 6, 10; have been converted into methacrylates by a dicyclohexylcarbodiimide activated esterification reaction.The resulting methacrylates show two disordering transitions prior to isotropization.Polarization optical microscopy indicates the occurrence of smectic liquid crystal phases.Organic solutions of the amphiphilic methacrylates showed a strong decrease in the surface tension at low concentrations.Peculiar surface activity had already been observed for the compound with the shortest fluorocarbon segment.Needle shaped crystallites of the semifluorinated compounds are formed when hydrocarbon solutions of methacrylates with a perfluorododecyl substituent are cooled.The crystals can form a fine mesh network which encloses the solvent in the cavities.The size of the needle crystals and the internal dimensions of the network depend strongly on the crystallization conditions.
- Hoepken, Jens,Faulstich, Sabine,Moeller, Martin
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