- Synthesis of copolyamides based on PA 66 bearing lithium sulfonate groups and having unique thermal properties
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Copolyamides of PA 66/6 lithium 5-sulfoisophthalic acid (LiSIPA) containing up to 40 mol % of LiSIPA were prepared in a 1L-pilot reactor operating at high pressures and high temperatures. Interestingly, the presence of lithium sulfonate moieties highly impacted the glass transition temperature of the polyamide. The Tg increased from 59 °C for PA 66 to 155 °C for a copolymer containing about 40 mol % of LiSIPA. 1,3- Dihexylbenzenedicarboxamide and lithium p-toluenesulfonate were synthesized as model compounds to investigate the interaction of lithium sulfonate moieties and amide functions. Infrared spectroscopy using ATR technology performed on mixture of both compounds showed that the carbonyl group of amide functions interacts with the lithium cation of lithium sulfonate moieties. Similar S-O and C-O adsorption bands were observed in copolyamides PA 66/6LiSIPA and in mixture of model compounds, which strongly suggest the formation in the copolyamides of physical cross-linking points centered on lithium cations coordinated by carbonyl groups of amide functions.
- Cammage, Geoffroy,Spitz, Roger,Boisson, Christophe,Rossin, Rene,Jeol, Stephane,Touraud, Franck
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- Onium borates/borates of organometallic complexes and cationic initiation of polymerization therewith
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Novel onium borates of an element of Groups 15 to 17 of the Periodic Table, or borates of an organometallic complex of an element of Groups 4 to 10 of the Periodic Table, well suited for the photochemical/electron beam cationic initiation of polymerization/crosslinking, the anionic borate moiety of which having the formula: in which a and b are integers ranging from 0 to 4 and a+b=4; the symbols X are each a halogen atom when a ranges up to 3 and an OH functional group when a ranges up to 2; and the symbols R, which may be identical or different, are each a phenyl radical substituted by at least one element or electron-withdrawing substituent or by at least two halogen atoms, or an aryl radical containing at least two aromatic ring members, or such aryl radical bearing at least one electron-withdrawing substituent.
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- Fluorinated diazabicycloalkane derivatives
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Fluorinated diazabicycloalkane derivative of the following Formula I: STR1 wherein n represents 0, 1 or 2; R represents a quaternizing organic group; each R1, R2, R3, R4 and R5 independently represents hydrogen, C1 -C6 alkyl, aryl, C1 -C6 alkyl-substituted aryl or aryl-substituted C1 -C6 alkyl and each X- independently represents a conterion or 2X- represents a single divalent counterion, are electrophilic fluorinating agents.
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- A SIMPLE METHOD FOR TOSYLATION WITH INVERSION
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In this paper we describe a simple one-step procedure for tosylation with inversion, using zinc tosylate, diethylazodicarboxylate and triphenylphospine.
- Galynker, Igor,Still, W. Clark
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p. 4461 - 4464
(2007/10/02)
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