A titanium oxide supported double metal cyanide (TiO2-DMC) was found to be a highly active cataly... more A titanium oxide supported double metal cyanide (TiO2-DMC) was found to be a highly active catalyst for the reaction of CO2 with propylene oxide to polyethercarbonates, which are useful polymer building blocks for polyurethane applications. The catalyst was prepared by coprecipitation of potassium hexacyanocobaltate(III) and titanium(IV) ethoxide with an excess amount of ZnCl2 under slightly acidic conditions.
Angewandte Chemie (International ed. in English), Jan 25, 2016
Transparent films were prepared by cross-linking polyunsaturated poly(ether carbonate)s obtained ... more Transparent films were prepared by cross-linking polyunsaturated poly(ether carbonate)s obtained by the multicomponent polymerization of CO2 , propylene oxide, maleic anhydride, and allyl glycidyl ether. Poly(ether carbonate)s with ABXBA multiblock structures were obtained by sequential addition of mixtures of propylene oxide/maleic anhydride and propylene oxide/allyl glycidyl ether during the polymerization. The simultaneous addition of both monomer mixtures provided poly(ether carbonate)s with AXA triblock structures. Both types of polyunsaturated poly(ether carbonate)s are characterized by diverse functional groups, that is, terminal hydroxy groups, maleate moieties along the polymer backbone, and pendant allyl groups that allow for versatile polymer chemistry. The combination of double bonds substituted with electron-acceptor and electron-donor groups enables particularly facile UV- or redox-initiated free-radical curing. The resulting materials are transparent and highly intere...
ABSTRACT The invention relates to a method for producing polyetherpolyols by reacting diols or po... more ABSTRACT The invention relates to a method for producing polyetherpolyols by reacting diols or polyols with ethylene oxide, propylene oxide, butylene oxide or mixtures thereof in the presence of a multi-metal cyanide complex catalyst. The reaction is performed in stirred-tank reactor and the reaction mixture is circulated via an externally located heat exchanger, using a pump.
The activation of CO2 is highlighted for two lead-structures of cobalt- and zinc-based homogeneou... more The activation of CO2 is highlighted for two lead-structures of cobalt- and zinc-based homogeneous catalysts used in the copolymerization of epoxides and CO2. Following the activation of CO2 with in-situ ATR-IR spectroscopy, a surprisingly facile insertion of CO2 into metal-phenoxide bonds was revealed.
A versatile and high yielding one-pot hydroformylation/Strecker synthesis is reported for the syn... more A versatile and high yielding one-pot hydroformylation/Strecker synthesis is reported for the synthesis of various alpha-aminonitriles. This methodology allows functionalization of dendrimers (e.g. polyamines 4-7) and hyper branched polymers (e.g. polyallyl glycerol 12) to give corresponding dendritic structures with alpha-aminonitriles and/or amino acids in the outer shell in good to excellent yields.
A titanium oxide supported double metal cyanide (TiO2-DMC) was found to be a highly active cataly... more A titanium oxide supported double metal cyanide (TiO2-DMC) was found to be a highly active catalyst for the reaction of CO2 with propylene oxide to polyethercarbonates, which are useful polymer building blocks for polyurethane applications. The catalyst was prepared by coprecipitation of potassium hexacyanocobaltate(III) and titanium(IV) ethoxide with an excess amount of ZnCl2 under slightly acidic conditions.
Angewandte Chemie (International ed. in English), Jan 25, 2016
Transparent films were prepared by cross-linking polyunsaturated poly(ether carbonate)s obtained ... more Transparent films were prepared by cross-linking polyunsaturated poly(ether carbonate)s obtained by the multicomponent polymerization of CO2 , propylene oxide, maleic anhydride, and allyl glycidyl ether. Poly(ether carbonate)s with ABXBA multiblock structures were obtained by sequential addition of mixtures of propylene oxide/maleic anhydride and propylene oxide/allyl glycidyl ether during the polymerization. The simultaneous addition of both monomer mixtures provided poly(ether carbonate)s with AXA triblock structures. Both types of polyunsaturated poly(ether carbonate)s are characterized by diverse functional groups, that is, terminal hydroxy groups, maleate moieties along the polymer backbone, and pendant allyl groups that allow for versatile polymer chemistry. The combination of double bonds substituted with electron-acceptor and electron-donor groups enables particularly facile UV- or redox-initiated free-radical curing. The resulting materials are transparent and highly intere...
ABSTRACT The invention relates to a method for producing polyetherpolyols by reacting diols or po... more ABSTRACT The invention relates to a method for producing polyetherpolyols by reacting diols or polyols with ethylene oxide, propylene oxide, butylene oxide or mixtures thereof in the presence of a multi-metal cyanide complex catalyst. The reaction is performed in stirred-tank reactor and the reaction mixture is circulated via an externally located heat exchanger, using a pump.
The activation of CO2 is highlighted for two lead-structures of cobalt- and zinc-based homogeneou... more The activation of CO2 is highlighted for two lead-structures of cobalt- and zinc-based homogeneous catalysts used in the copolymerization of epoxides and CO2. Following the activation of CO2 with in-situ ATR-IR spectroscopy, a surprisingly facile insertion of CO2 into metal-phenoxide bonds was revealed.
A versatile and high yielding one-pot hydroformylation/Strecker synthesis is reported for the syn... more A versatile and high yielding one-pot hydroformylation/Strecker synthesis is reported for the synthesis of various alpha-aminonitriles. This methodology allows functionalization of dendrimers (e.g. polyamines 4-7) and hyper branched polymers (e.g. polyallyl glycerol 12) to give corresponding dendritic structures with alpha-aminonitriles and/or amino acids in the outer shell in good to excellent yields.
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