0000000000014039

AUTHOR

Helmut Ritter

showing 44 related works from this author

Cyclodextrins in polymer synthesis: polymerization of methyl methacrylate under atom-transfer conditions (ATRP) in aqueous solution

2000

Host guest complexes of methyl methacrylate (MMA) and randomly methylated β-cyclodextrin (m-β-CD, 1 a) were polymerized in aqueous medium using atom-transfer radical polymerization. Ethyl 2-bromoisobutyrate (EBIB) was used as an initiator, copper(I) bromide as the catalyst, and bipyridine (bipy) or 4,4′-di-(5-nonyl)-2,2´-bipyridine (dNbipy) as ligands. The unthreading of m-β-CD during the polymerization led to water-insoluble poly(methyl methacrylate) (PMMA). It was found that using dNbipy resulted in higher monomer conversion than using bipy as the ligand under similar conditions. Furthermore, it is shown that the polymerization of MMA under these conditions has a living character. The pol…

Polymers and PlasticsChemistryOrganic ChemistryRadical polymerizationPhotochemistryLiving free-radical polymerizationchemistry.chemical_compoundEnd-groupChain-growth polymerizationPolymerizationPolymer chemistryMaterials ChemistryReversible addition−fragmentation chain-transfer polymerizationMethyl methacrylateIonic polymerizationMacromolecular Rapid Communications
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Pharmakologisch aktive polymere, 9. Synthese und untersuchung makromolekularer derivate des 1-adamantanamins

1976

Es wurden zwei Methacrylatmonomere (3 und 6) dargestellt, welche die 1-Adamantylamino-Gruppe mit verschiedenen Spacergruppen enthalten. Die neuen Monomeren wurden mit 2-Methylsulfinylathylmethacrylat zu wasserloslichen Produkten copolymerisiert. Die Copolymeren mit 1-Adamantylamino-Gruppen sowie eine Modellsubstanz ohne Adamantyl-Gruppe wurden in vitro und in vivo auf ihre Wirkung gegen InfluenzaViren untersucht. Two methacrylate monomers (3 and 6) containing 1-adamantylamino groups with different spacer groups were prepared. The new monomers were copolymerized with 2-methylsulfinylethyl methacrylate to yield water soluble products. The copolymers containing the 1-adamantylamino group and a…

ChemistryPolymer chemistryDie Makromolekulare Chemie
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Einfluss von Cyclodextrinen auf die Synthese und das thermoreversible Lösungsverhalten vonN-Isopropylacrylamid-Copolymeren mit Adamantylresten in den…

2003

ChemistryGeneral MedicineAngewandte Chemie
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Nanoparticle Vesicles Through Self Assembly of Cyclodextrin- and Adamantyl-Modified Silica

2010

Stable nanoparticle vesicles were for the first time prepared from adamantyl- and cyclodextrin (CD)-modified silica nanoparticles forming host-guest interactions in aqueous solution. Adamantyl-functionalized nanoparticles were obtained from thiol-isocyanate reaction of thiol-modified nanoparticles with 1-adamantyl isocyanate. The CD modified silica particles were isolated from a reaction of mono-6-para-toluenesulfonyl-β-cyclodextrin with the thiol functionalized silica under microwave conditions in basic media. The obtained particles were characterized in respect of agglomeration and self-assembly behavior in aqueous solution by dynamic light scattering and transmission electron microscopy.…

chemistry.chemical_classificationAqueous solutionNanostructureMaterials sciencePolymers and PlasticsCyclodextrinVesicleOrganic ChemistryNanoparticleInclusion compoundchemistry.chemical_compoundDynamic light scatteringchemistryChemical engineeringPolymer chemistryMaterials ChemistrySelf-assemblyMacromolecular Rapid Communications
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Cyclodextrins in Polymer Synthesis:  Free-Radical Polymerization of Methylated β-Cyclodextrin Complexes of Methyl Methacrylate and Styrene Controlled…

2000

Nitroxide mediated radical polymerizationPolymers and PlasticsChemistryOrganic ChemistryRadical polymerizationChain transferInorganic ChemistryEnd-groupLiving free-radical polymerizationPolymerizationPolymer chemistryMaterials ChemistryLiving polymerizationReversible addition−fragmentation chain-transfer polymerizationMacromolecules
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Enzymatically catalyzed synthesis of photocrosslinkable oligophenols

2000

The HRP-catalyzed oligomerization of cinnamoyl-hydroquinone-ester and cinnamoyl-4-hydroxyanilide led to the formation of soluble polyphenols. The oligomers were synthexized in water/1,4-dioxane and in water/acetone mixtures and characterized by NMR, FTIR and SEC. Upon UV treatment of the homogenoes films the polyphenols were crosslinked due to [2+2]-cycloadditions of the cinnamoyl functions.

Polymers and PlasticsbiologyOrganic ChemistryCondensed Matter PhysicsOligomerCatalysisEnzyme catalysischemistry.chemical_compoundchemistryPhotosensitivityPolyphenolPolymer chemistryMaterials ChemistryAcetonebiology.proteinOrganic chemistryPhenolsPhysical and Theoretical ChemistryPeroxidaseMacromolecular Chemistry and Physics
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Cyclodextrins in polymer synthesis: free radical polymerisation of cyclodextrin complexes of cyclohexyl and phenyl methacrylate in aqueous medium

1998

The polymerisation mechanism of 2,6-dimethyl-β-cyclodextrin (Me2-β-CD) complexes of phenyl methacrylate (1) and cyclohexyl methacrylate (2) is described. The polymerisation of the complexes 1 a and 2a was carried out in water with potassium peroxodisulfate/potassium hydrogensulfite as initiator. The unthreading of the Me2-β-CD during the polymerisation led to water-insoluble poly(phenyl methacrylate) (1b) and poly(cyclohexyl methacrylate) (2b). By comparison, analogously prepared polymers from uncomplexed monomers 1 and 2 in homogeneous organic solvent (THF) with AIBN as radical initiator showed significantly lower viscosities and were obtained in lower yields in both cases.

chemistry.chemical_classificationPolymers and PlasticsCyclodextrinChemistryPotassiumOrganic Chemistrychemistry.chemical_elementSolution polymerizationPolymerMethacrylatechemistry.chemical_compoundMonomerPolymerizationPolymer chemistryMaterials ChemistryRadical initiatorMacromolecular Rapid Communications
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Innentitelbild: Fluorescent Nanowires Self-Assembled through Host-Guest Interactions in Modified Calcein (Angew. Chem. 32/2011)

2011

Calceinchemistry.chemical_compoundchemistryNanowireNanotechnologyGeneral MedicineFluorescenceSelf assembledAngewandte Chemie
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Cyclodextrins in polymer synthesis: free radical polymerization of cyclodextrin host-guest complexes of methyl methacrylate or styrene from homogenou…

2000

The polymerization of methylated β-cyclodextrin (m-β-CD) 1 : 1 host-guest compounds of methyl methacrylate (MMA) (1) or styrene (2) is described. The polymerization of complexes 1 a and 2 a was carried out in water with potassium peroxodisulfate (K2S2O8)/sodium hydrogensulfite (NaHSO3) as radical redox initiator at 60°C. Unthreading of m-β-CD during the polymerization led to water-insoluble poly(methyl methacrylate) (PMMA) (3) and polystyrene (4). By comparison, analogously prepared polymers from uncomplexed monomers 1 and 2 in ethanol as organic solvent with 2,2′-azoisobutyronitrile (AIBN) as radical initiator showed significantly lower molecular weights and were obtained in lower yields i…

Living free-radical polymerizationPolymers and PlasticsPolymerizationBulk polymerizationChemistryOrganic ChemistryPolymer chemistryRadical polymerizationMaterials ChemistryPrecipitation polymerizationReversible addition−fragmentation chain-transfer polymerizationChain transferIonic polymerizationMacromolecular Rapid Communications
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Synthesis of Macromolecular Substances by Addition Polymerization

2001

As already explained, polymerization reactions can proceed by various mechanisms and can be catalyzed by initiators of different kinds. For addition polymerization of single compounds, initiation of chains may occur via radical, cationic, anionic, or so-called coordinative-acting initiators, but some monomers will not polymerize by more than one mechanism. Both thermodynamic and kinetic factors can be important, depending on the structure of the monomer and its electronic and steric situation. The most important initiators are summarized in Table 3.1.

Steric effectschemistry.chemical_compoundMonomerAnionic addition polymerizationchemistryPolymerizationfungiMacromolecular SubstancesPolymer chemistryVinyl acetateCationic polymerizationfood and beveragesAddition polymer
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Switchable Supramolecular Crosslinking of Cyclodextrin-Modified Hyperbranched Polyethylenimine via Anthraquinone Dyes

2011

Two anthraquinone dyes, 5,8-di-N-adamantylamino-1,4-dihydroxyanthraquinone (AQ-OH) and 1,4-di-N-adamantylaminoanthraquinone (AQ-H), are synthesized. The combination of AQ-OH and AQ-H with hyperbranched polyethylenimine (PEI) bearing covalently attached β-cyclodextrin spontaneously formed host–guest complexes with hydrodynamic diameters of about 260 nm. Even enlarged structures of the trifunctional AQ-H were observed via DLS. Repeated measurements show that their assembly and disassembly is reversible with a critical point at 26 °C and therefore switchable via temperature. Also superstructures up to 100 μm were detected via TEM, cryo-TEM-, and SEM. Hence, a smart colored network of switchabl…

chemistry.chemical_classificationPolyethyleniminePolymers and PlasticsCyclodextrinOrganic ChemistrySupramolecular chemistryCondensed Matter PhysicsAnthraquinonechemistry.chemical_compoundchemistryCovalent bondOrganic dyePolymer chemistryMaterials ChemistryPhysical and Theoretical ChemistryWater soluble polymersMacromolecular Chemistry and Physics
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Cyclodextrins in Polymer Synthesis: Supramolecular Cyclodextrin Complexes of Pyrrole and 3,4-Ethylenedioxythiophene and Their Oxidative Polymerization

2000

chemistry.chemical_classificationchemistry.chemical_compoundMaterials sciencechemistryCyclodextrinPolymerizationMechanics of MaterialsMechanical EngineeringPolymer chemistrySupramolecular chemistryGeneral Materials SciencePolymerPyrroleAdvanced Materials
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New Photosensitive Polymers:  Synthesis and Free Radical Polymerization of Oxypyridinium and Oxyisoquinolinium Functionalized Methacrylate and Styren…

2002

Polymerizable hydroxypyridinium and hydroxyisoquinolinium salts 1a−4a, 2d, and 3d have been prepared from vinylbenzyl chloride or glycidyl methacrylate and 3-hydroxypyridine (2), 4- or 5-hydroxyisoquinoline (1, 3), and 8-hydroxyquinoline (4). Radical homo- and copolymerization with styrene or methyl methacrylate of the salts 1a−3a, 2d, and 3d produced (co)polymers 1e, 2e, 2f, 3f, 1g, 2g, 2h, and 3h. The photosensitive dipolar oxypyridinium or oxyisochinolinium betaine structures were generated in solutions with triethylamine from the low molecular weight and polymeric salt precursors. For the model compounds 1b−4b and (co)polymers 1e, 2e, 2f, 3f, 1g, 2g, 2h, and 3h, the degradation of the l…

Glycidyl methacrylatePolymers and PlasticsOrganic ChemistryRadical polymerizationPhotochemistryMethacrylatePolyelectrolyteStyreneInorganic Chemistrychemistry.chemical_compoundchemistryPolymer chemistryMaterials ChemistryCopolymerMethyl methacrylateTriethylamineMacromolecules
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Synthesis and radical polymerization of novel methacrylates with mesoionic 6-oxo-1,6-dihydropyrimidin-3-ium-4-olates as photosensitive components

2001

New polymerizable mesoionic 6-oxo-1,6-dihydropyrimidin-3-ium-4-olates 5a-f have been synthesized using tosylated 2-hydroxymethyl methacrylate and various thioureas and malonic acids. Radical polymerization of the mesoionic derivatives 5a, c, d, e with AIBN as initiator resulted in soluble polymers, which were used for the preparation of photosensitive films.

chemistry.chemical_classificationPolymers and PlasticsChemistryGeneral Chemical EngineeringRadical polymerizationMesoionicChemical modificationGeneral ChemistryPolymerMethacrylatechemistry.chemical_compoundPhotosensitivityPolymerizationPolymer chemistryMaterials ChemistryCopolymerOrganic chemistryDesigned Monomers and Polymers
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Supramolecular Nanocycles Comprisingβ-Cyclodextrin-click-Ferrocene Units: Rings of Rings of Rings

2010

We applied 1,3-dipolar cycloaddition to bind ethynylferrocene onto 6I-azido-6I-deoxycyclomaltoheptaose under microwave assisted conditions. The process was investigated by (1) H NMR, FT-IR spectroscopy, and MALDI-TOF mass spectrometry. The ability of the synthesized compound to self-organize to cyclic supramolecular structures was investigated by dynamic light scattering measurements and cryo-transmission electron microscopy.

chemistry.chemical_classificationPolymers and PlasticsCyclodextrinOrganic ChemistrySupramolecular chemistrymacromolecular substancesCycloadditionInclusion compoundchemistry.chemical_compoundchemistryFerrocenePolymer chemistry13-Dipolar cycloadditionMaterials ChemistryProton NMROrganic chemistryMetalloceneMacromolecular Rapid Communications
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Synthesis of Macromolecular Substances by Condensation Polymerization and Stepwise Addition Polymerization

2001

Condensation polymerizations (polycondensations) are stepwise reactions between bifunctional or polyfunctional components, with elimination of simple molecules such as water or alcohol and the formation of macromolecular substances. For the preparation of linear condensation polymers from bifunctional compounds (the same considerations apply to polyfunctional compounds which then lead to branched or crosslinked condensation polymers) there are basically two possibilities. One either starts from a monomer which has two unlike groups suitable for polycondensation (AB type), or one starts from two different monomers, each possessing a pair of identical reactive groups that can react with each …

chemistry.chemical_compoundEnd-groupCondensation polymerChain-growth polymerizationAnionic addition polymerizationPolymerizationchemistryPolymer chemistryCationic polymerizationAddition polymerOrganic chemistryBifunctional
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Influence of Cyclodextrin Molecules on the Synthesis and the Thermoresponsive Solution Behavior of N-Isopropylacrylamide Copolymers with Adamantyl Gr…

2003

chemistry.chemical_classificationCyclodextrinChemistryPolymer chemistrySide chainCopolymerOrganic chemistryMoleculeGeneral ChemistryCatalysisAngewandte Chemie International Edition
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Oligo(ether sulfones). 3. Block Copolymers via Condensation Reactions of Telechelic Oligo(ether sulfones) Bearing Phenolic Endgroups and Oligomeric α…

1999

Telechelic polymerBearing (mechanical)Polymers and PlasticsOrganic ChemistryEtherCondensation reactionlaw.inventionInorganic Chemistrychemistry.chemical_compoundchemistrylawPolymer chemistryMaterials ChemistryCopolymerOrganic chemistryMacromolecules
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Cyclodextrins in polymer chemistry: Influence of methylated β-cyclodextrin as host on the free radical copolymerization reactivity ratios of isoborny…

1999

Methylated β-cyclodextrin (me-β-CD) was used to complex the hydrophobic monomers isobornyl acrylate (1) and butyl acrylate (2) yielding the water-soluble host/guest complexes isobornyl acrylate/me-β-CD (1a) and butyl acrylate/me-β-CD (2a). The included monomers were copolymerized in water by free-radical mechanism and the kinetics were studied. In order to evaluate these results, the corresponding uncomplexed monomers 1 and 2 were also copolymerized in organic solution. The reactivity ratios of 1a and 2a (r1a = 0.3, r2a = 1.7) differ significantly from the reactivity ratios of the corresponding uncomplexed acrylates 1 and 2 in organic solution (r1 = 1.3, r2 = 1.0). In addition, we found tha…

chemistry.chemical_classificationAqueous solutionPolymers and PlasticsCyclodextrinButyl acrylateOrganic ChemistryPolymerInclusion compoundchemistry.chemical_compoundMonomerchemistryPolymer chemistryMaterials ChemistryCopolymerOrganic chemistryReactivity (chemistry)Macromolecular Rapid Communications
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Cyclodextrins in Polymer Synthesis:  Influence of Acrylate Side Groups on the Initial Rate of Radical Polymerization of Various Acrylate/Methylated β…

2001

Methylated β-cyclodextrin was used to complex the hydrophobic monomers n-propyl acrylate (1), n-butyl acrylate (2), n-pentyl acrylate (3), n-hexyl acrylate (4), and cyclohexyl acrylate (5) respectively yielding the corresponding water-soluble host/guest-complexes 1a−5a. The complexes were polymerized in water by free radical mechanism and the initial polymerization rates (v0) determined. We found that v0 increases as follows:  1a (12.5), 2a (27.5), 3a (44.2), 5a (49.4), 4a (75.8 × 10-6 mol·L-1·s-1). To investigate the influence of the hydrophobic character of the guest monomers on the reaction rate, the water solubilities of the uncomplexed monomers 1−5 were determined by HPLC measurements.…

chemistry.chemical_classificationAcrylateAqueous solutionPolymers and PlasticsCyclodextrinOrganic ChemistryRadical polymerizationSolution polymerizationInclusion compoundInorganic Chemistrychemistry.chemical_compoundMonomerchemistryPolymerizationPolymer chemistryMaterials ChemistryMacromolecules
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Cyclodextrins in polymer synthesis: photocrosslinkable films via free radical copolymerization of methylated β-cyclodextrin-complexed styrene with so…

2001

The copolymerization of a methylated-β-cyclodextrin (m-β-CD) 1:1 host-guest compound of styrene (1a) with various molar ratios of sodium 4-(acrylamido)-phenyldiazosulfonate (2) is described. The copolymerization of complex 1a with 2 was carried out in water with 2,2′-azobis(N,N′-dimethyleneisobutyramidine)-dihydrochloride as the free radical initiator at 40°C. Depending on the amount of 2 incorporated in the copolymer, water- or DMF-soluble copolymers of high molar mass were obtained. Irradiation of the copolymers with UV light in solution resulted in rapid decomposition of the azo chromophore, and irradiation of the polymers as films led to crosslinking and thus to insolubility.

chemistry.chemical_classificationAqueous solutionMolar massMaterials sciencePolymers and PlasticsGeneral Chemical EngineeringGeneral ChemistryPolymerInclusion compoundStyrenechemistry.chemical_compoundMonomerchemistryPolymer chemistryMaterials ChemistryCopolymerRadical initiatorDesigned Monomers and Polymers
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Fluorescent Nanowires Self-Assembled through Host-Guest Interactions in Modified Calcein

2011

Calceinchemistry.chemical_compoundNanostructureChemistryNanowireNanotechnologyGeneral ChemistrySelf-assemblyGeneral MedicineHost (network)FluorescenceCatalysisSelf assembledAngewandte Chemie
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Cyclodextrins in polymer synthesis: Influence of methylated β-cyclodextrin as host on the free radical copolymerization reactivity ratios of hydropho…

2001

Methylated (β-cyclodextrin (me-β-CD) was used to complex the hydrophobic monomers n-butyl acrylate (1), n-hexyl acrylate (2) and cyclohexyl acrylate (3) yielding the corresponding water soluble host/guest complexes 1a–3a. The complexes were copolymerized in water by free radical mechanism and the reactivity ratios were determined by measuring the monomer consumption by HPLC. The following reactivity ratios were found: copolymerization of 1a and 2a: r1= 1.01 ± 0.01; r2= 1.04 ± 0.01; copolymerization of 3a and 2a: r1= 0.74; r2= 1.28; copolymerization of 3a and 1a: r1= 0.75 ± 0.04; r2= 1.13 ± 0.01. In contrast to that, the copolymerization of the uncomplexed monomers 1–3 in organic medium (DMF…

chemistry.chemical_classificationAcrylateMethylated β cyclodextrinPolymers and PlasticsAqueous mediumChemistrytechnology industry and agriculturemacromolecular substancesGeneral ChemistryPolymerCondensed Matter PhysicsHigh-performance liquid chromatographychemistry.chemical_compoundMonomerPolymer chemistryMaterials ChemistryCopolymerReactivity (chemistry)Polymer Bulletin
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Inside Cover: Fluorescent Nanowires Self-Assembled through Host-Guest Interactions in Modified Calcein (Angew. Chem. Int. Ed. 32/2011)

2011

Calceinchemistry.chemical_compoundchemistryPolymer chemistryNanowireGeneral ChemistrySelf-assemblyPhotochemistryFluorescenceCatalysisSelf assembledAngewandte Chemie International Edition
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Oxidative oligomerization of cyclodextrin-complexed bifunctional phenols catalyzed by horseradish peroxidase in water

2000

The HRP-catalyzed oligomerization of hydrophobic bifunctional phenols in water was realized by the use of 2,6-di-O-methylated β-cyclodextrin. The molecular weights of the resulting oligomers were in the same region as they were reached by conventional HRP-catalyzed oligomerizations in water/dioxane-mixtures. The polymerizable moieties, maleimide and methacrylamide, were not affected during the oligomerization process, as proofed by NMR, MALDI-TOF and FT-IR measurements. It was therefore possible to get soluble functionalized oligomers, which were crosslinked via radical copolymerization with suitable components (styrene, MMA) or heating.

chemistry.chemical_classificationPolymers and PlasticsbiologyCyclodextrinOrganic ChemistryCondensed Matter PhysicsHorseradish peroxidaseStyrenechemistry.chemical_compoundchemistryPolymer chemistryMaterials ChemistryCopolymerbiology.proteinMethacrylamideOrganic chemistryPhenolsPhysical and Theoretical ChemistryBifunctionalMaleimideMacromolecular Chemistry and Physics
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Cyclodextrin and Adamantane Host-Guest Interactions of Modified Hyperbranched Poly(ethylene imine) as Mimetics for Biological Membranes

2011

Models MolecularSurface PropertiesAdamantaneImineBeta-CyclodextrinsAdamantaneCatalysischemistry.chemical_compoundBiomimeticsPolymer chemistryMoleculeParticle SizeFluorescent Dyeschemistry.chemical_classificationCyclodextrinMolecular StructureChemistryCell Membranebeta-CyclodextrinsBiological membraneGeneral ChemistryGeneral MedicineFluoresceinsMembraneSelf-assemblyIminesPolyethylenesAngewandte Chemie
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Cyclodextrins in polymer synthesis: Free radical polymerization of methylated β-cyclodextrin complexes of methyl methacrylate and styrene, controlled…

2000

Methylated β-cyclodextrin (me-β-CD) was used to complex the hydrophobic monomers methyl methacrylate (1) or styrene (2) yielding the water-soluble 1 : 1-host/guest complexes methyl methacrylate/me-β-CD (1 a) and styrene/me-β-CD (2 a), respectively. In addition, the hydrophobic chain-transfer agent dodecanethiol (3) was complexed by two equivalents of me-β-CD yielding the water-soluble dodecanethiol/me-β-CD (3 a). The included monomers were polymerized in water by a free-radical mechanism in the presence of 3 a as the chain-transfer agent. The chain-transfer constants were determined. In order to evaluate these results, the chain-transfer constants of 3 were also determined in the case of th…

chemistry.chemical_classificationPolymers and PlasticsCyclodextrinOrganic ChemistryRadical polymerizationChain transferCondensed Matter PhysicsStyreneInclusion compoundchemistry.chemical_compoundMonomerchemistryPolymerizationPolymer chemistryMaterials ChemistryPhysical and Theoretical ChemistryMethyl methacrylateMacromolecular Chemistry and Physics
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Cyclodextrins in Polymer Synthesis: Enantiodiscrimination in Free-Radical Polymerization of Cyclodextrin-Complexed Racemic N -Methacryloyl-D,L -pheny…

2003

The enantiodiscriminating polymerization of racemic cyclodextrin-complexed N-methacryloylphenylalanine methyl ester is investigated 1 H NMR spectra of the complexes with methylated β-cyclodextrin in D 2 O manifest splittings due to chiral recognition. The different stabilities of the diastereomeric complexes influence the kinetics of the homopolymerization, particularly at 0°C. An enrichment of the residual N-methacryloyl-L-phenylalanine methyl ester of 14% was achieved after 21 h of polymerization.

chemistry.chemical_classificationReaction mechanismPolymers and PlasticsCyclodextrinOrganic ChemistryRadical polymerizationtechnology industry and agricultureDiastereomerPolymerchemistry.chemical_compoundMonomerchemistryPolymerizationPolymer chemistrypolycyclic compoundsMaterials ChemistryProton NMRMacromolecular Rapid Communications
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Cellulose-click-ferrocenes as docking spots for cyclodextrin

2012

A novel synthesis of ferrocene-modified cellulose, prepared from 6-azido-6-deoxy-cellulose and ethynylferrocene, is presented. The two components were coupled via copper-catalyzed click-type cycloaddition under microwave-assisted conditions. The surface structure of the cellulose derivative was investigated in comparison with that of pure, microcrystalline cellulose using electron microscopy (scanning, transmission and scanning transmission), showing iron atoms of ferrocene as homogeneously distributed particles. They are detectable as clear signals in the energy-dispersive X-ray profile. In addition, Rame-β-cyclodextrin was supramolecularly attached to cellulose and the complex formed was …

chemistry.chemical_classificationMaterials sciencePolymers and PlasticsCyclodextrinOrganic ChemistryCycloadditionlaw.inventionMicrocrystalline cellulosechemistry.chemical_compoundFerrocenechemistryDynamic light scatteringlawPolymer chemistryMaterials ChemistryClick chemistryElectron microscopeCellulosePolymer International
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Chemoenzymatic synthesis of a poly(hydroquinone)

1999

Chemoenzymatic synthesis of a poly(hydroquinone) was achieved by enzymatic oxidative polymerization of 4-hydroxyphenyl benzoate, followed by alkaline hydrolysis of the resulting polymer. The polymerization of 4-hydroxyphenyl benzoate was performed using a peroxidase and hydrogen peroxide as catalyst and oxidizing agent, respectively, in an aqueous organic solvent. Soybean peroxidase afforded the polymer in good yields. IR analysis of the polymer showed the formation of the polymer consisting of a mixture of phenylene and oxyphenylene units. By alkaline hydrolysis of the resulting polymer, benzoate moiety was completely removed to give poly(hydroquinone).

chemistry.chemical_classificationPolymers and PlasticsHydroquinoneOrganic ChemistryPolymerAlkaline hydrolysis (body disposal)Condensed Matter Physicschemistry.chemical_compoundchemistryPolymerizationPhenyleneOxidizing agentPolymer chemistryMaterials ChemistryMoietyOrganic chemistryPhysical and Theoretical ChemistryHydrogen peroxideMacromolecular Chemistry and Physics
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1976

A number of acryl and methacryl derivatives of different sulfanilamides (1a—I) were prepared and polymerized. The fixation of the sulfonamide to the polymerizable group was carried out directly, using the acryl- and methacrylamides, and by means of spacer groups, to favour the enzymatic or hydrolytic release of the drug moiety. Selected sulfonamide types of different pKA values were used, and the pH-dependant solubility of the corresponding polymers was studied. The monomeric acryloyl and methacryloyl sulfonamides were homopolymerized radically by AIBN. For distribution studies polysulfadiazineacrylamide, 14C-labelled in the main chain (2e'), was synthesized. Copolymerization with 2-methyls…

chemistry.chemical_classificationSulfanilamideMethacrylateBiodegradable polymerSulfonamidechemistry.chemical_compoundMonomerAnionic addition polymerizationchemistryPolymer chemistrymedicineCopolymerMoietymedicine.drugDie Makromolekulare Chemie
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Polymeric mesoions, 4. Synthesis of polymerizable mesoionic 4,6-dioxo-1,3-diazines derived from vinylbenzylmalonic acid

2000

Vinylbenzylmalonic acid (4) was condensed with N,N'-diphenylformamidine (5a), N,N'-diphenylacetamidene (5b), S-propyl-1,3-diphenylisothiourea (6) and anilinopyridine (7) in the presence of dicyclohexylcarbodiimide (DDC). The resulting new mesoionic monomers 8a-d were polymerized with 2,2'-azoisobutyronitrile (AIBN) as an initiator and dodecanethiol as a chain transfer agent. The low molecular weight model compounds 5-benzyl-pyrido[1,2-a]pyrimidine-2,4-dione (9a) and 5-hexadecyl-4,6-dioxo-1,3-diphenyl-2-hexadecylthio-1,3-diazine (9b) were prepared for X-ray diffraction analysis and comparison of spectrospical data.

Polymers and PlasticsChemistryOrganic ChemistryRadical polymerizationMesoionicCrystal structureCondensed Matter PhysicsChemical synthesischemistry.chemical_compoundMonomerPolymerizationTransfer agentPolymer chemistryMaterials ChemistryOrganic chemistryPhysical and Theoretical ChemistryMacromolecular Chemistry and Physics
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Investigation of polymers in the mass spectrometer, 7. Pyrolysis-gas chromatography-mass spectrometry of low molecular and high polymeric sulfanilami…

1975

A number of low molecular, monomeric and polymeric sulfanilamide derivatives, which have found interest as possibly selective antitumour agents, were investigated by pyrolysis-gas chromatography (GC)-mass spectrometry (MS). Thermal degradation mechanisms were studied using also direct polymer pyrolysis in the ion source of the mass spectrometer. Thermal degradation products as well as low molecular weight sulfanilamides and related model compounds were characterized in their fragmentation behaviour by low and high resolution electron impact and field desorption mass spectrometry. Thermal fragments of structural significance were found, and a differentiation of the low and high molecular sul…

chemistry.chemical_classificationSulfanilamidePolymerMass spectrometryIon sourcePyrolysis–gas chromatography–mass spectrometrychemistry.chemical_compoundMonomerchemistryFragmentation (mass spectrometry)Polymer chemistrymedicineElectron ionizationmedicine.drugDie Makromolekulare Chemie
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Cyclodextrins in Polymer Synthesis:  Free Radical Copolymerization of Methylated β-Cyclodextrin Complexes of Hydrophobic Monomers with N-Isopropylacr…

2000

Methylated β-cyclodextrin (me-β-CD) was used to form water-soluble host/guest complexes with the hydrophobic monomers n-butyl methacrylate (1), cyclohexyl methacrylate (2), isobornyl acrylate (3), isobornyl methacrylate (4), and styrene (5), respectively. The free-radical copolymerizations of the water-soluble N-isopropylacrylamide (NIPAAm) with these complexed monomers were carried out in water at different molar ratios.

chemistry.chemical_classificationPolymers and PlasticsAqueous mediumCyclodextrinOrganic ChemistryPolymerMethacrylateInclusion compoundStyreneInorganic Chemistrychemistry.chemical_compoundMonomerchemistryPolymer chemistryMaterials ChemistryCopolymerMacromolecules
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Polymeric nitrones, 1. Synthesis and modification of polymeric nitrones derived from polymerizable aldehydes

1999

The model compound N,C-diphenylnitrone[N-(benzylidene)aniline-N-oxide] (3) was prepared by condensation of benzaldehyde with phenylhydroxylamine to study its thermal stability. X-ray diffraction analysis of a single crystal established the conformation of the nitrone group. A new monomer 4-(methacryloyloxy)benzaldehyde-phenylnitrone (8) was also prepared and could not be polymerized with 2,2′-azobisisobutyronitrile (AIBN) as initiator at 70°C. Under these conditions the nitrone reacted exclusively in an intermolecular 1,3-dipolar cycloaddition to give oligomeric tetrahydro-1,2-oxazoline derivates. The kinetics of the cycloaddition was investigated. Additionally, different (meth)acryl- and s…

chemistry.chemical_classificationPolymers and PlasticsOrganic ChemistryRadical polymerizationCondensed Matter PhysicsCondensation reactionAldehydeCycloadditionNitroneBenzaldehydechemistry.chemical_compoundMonomerchemistryPolymer chemistryMaterials ChemistryPhysical and Theoretical ChemistryPhenylhydroxylamineMacromolecular Chemistry and Physics
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Oxidative Copolymerisation ofpara-Functionalized Phenols Catalyzed by Horseradish peroxidase and Thermocrosslinking via Diels-Alder and (1+3) Cycload…

2001

The horseradish peroxidase- (HRP-) catalyzed polyrecombination of N-(4-hydroxyphenyl)-2-furamide (2) and 4-hydroxyphenylmaleimide (1) is described. The resulting copolymer was used to build crosslinked materials via Diels-Alder and cycloaddition reactions. We followed the enzymatic copolymerization process of an equimolar mixture of 1 and 2 using high pressure liquid chromatography (HPLC), size-exclusion chromatography (SEC) and by matrix assisted laser desorption/ionization-time of flight mass spectroscopy (MALDI-TOF MS) analysis and found that the polymerization of 2, which has a significant higher highest occupied molecular orbital (HOMO) energy, proceeds much faster. The HOMO energies o…

Polymers and PlasticsbiologyChemistryBioengineeringPhotochemistryMass spectrometryHorseradish peroxidaseCycloadditionCatalysisBiomaterialschemistry.chemical_compoundMonomerPolymerizationPolymer chemistryMaterials Chemistrybiology.proteinCopolymerHOMO/LUMOBiotechnologyMacromolecular Bioscience
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Cyclodextrins in Polymer Synthesis: Synthesis and Influence of Methylatedβ-Cyclodextrin on the Radical Polymerization Behavior of 1,1-Disubstituted 2…

2001

The chemical and enzymatic hydrolyses of 1,1-diethoxycarbonyl-2-vinylcyclopropane (1) were investigated. The product of the pig liver esterase (PLE)-catalyzed hydrolysis of 1 is a chiral trans monoester of 2-vinylcyclopropane dicarboxylic acid. New 1,1-disubstituted 2-vinylcyclopropane monomers (2a, b) were synthesized by the esterification of this ester. Methylated β-cyclodextrin was used to complex monomers 2a, b, yielding water-soluble 1 : 1 host/guest complexes. These complexes were polymerized in aqueous media by a free-radical ring-opening mechanism.

chemistry.chemical_classificationPolymers and PlasticsCyclodextrinOrganic ChemistryRadical polymerizationPolymerEsterasechemistry.chemical_compoundHydrolysisMonomerDicarboxylic acidchemistryPolymerizationPolymer chemistryMaterials ChemistryOrganic chemistryMacromolecular Rapid Communications
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Cyclodextrins in polymer synthesis: Free radical polymerization of cyclodextrin complexes withN-methacryloyl-11-aminoundecanoic acid orN-methacryloyl…

1998

The hydrophobic monomers N-methacryloyl-11 -aminoundecanoic acid (1) or N-methacryloyl-1-aminononane (2) were incorporated as guests into the cavity of heptakis(2,6-di-O-methyl)-β-cyclodextrin (Me 2 -β-CD) as a host, yielding the water compatible monomers N-methacryloyl-l 11-aminoundecanoic acid/ Me 2 -β-CD-complex (1a) and N-methacryloyl-1 -aminononane/Me 2 -β-Cl complex (2a). These complexes were polymerized radically in aqueous medium. The resulting polymers 1b and 2b which were obtained from the complexes 1a and 2a, are insoluble in water because of the unthreading of the cyclodextrin during the polymerization. The polymerization rate of 1a and 2a is high in comparison to the rate of th…

chemistry.chemical_classificationPolymers and PlasticsCyclodextrinChemistryOrganic ChemistryRadical polymerizationSolution polymerizationPolymerCondensed Matter PhysicsRing-opening polymerizationPolyelectrolytechemistry.chemical_compoundMonomerPolymerizationPolymer chemistryMaterials ChemistryPhysical and Theoretical ChemistryMacromolecular Chemistry and Physics
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Polyreaktionen in orientierten systemen, 6.Mizellare assoziationen in 4-vinylpyridiniumsalzlösungen

1975

Kritische Mizellkonzentrationen (cmc) aus Oberflachenspannungsmessungen und durch Farbstoffsolubilisierung werden von 4-Vinylpyridinium- bzw. 4-Athylpyridinium-Salzlosungen bestimmt. Erhohung der Gegenionen-Konzentration erniedrigt die cmc; gleichzeitig damit andert sich auch die Zusammensetzung der Polymerisationsprodukte der spontanen Polymerisation in Wasser. Mogliche Erklarungen hierfur werden diskutiert. Critical micell concentrations (cmc) of 4-vinylpyridinium or 4-ethylpyridinium salt solutions are determined from surface tension measurements and solubilisation of a dyestuff. Increase of the concentration of the gegenions decreases the cmc; at the same time, the composition of the po…

PolymerizationChemistryPolymer chemistryDie Makromolekulare Chemie
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Cyclodextrins in polymer synthesis: free radical polymerization of cyclodextrin complexes with oxazoline-functionalized vinyl monomers as guest molec…

2000

The synthesis of five new oxazoline functionalized vinyl monomers N-[4-(4′,5′-dihydrooxazol-2-yl)phenyl]acrylamide (3 a), N-[4-(4′,5′-dihydrooxazol-2-yl)phenyl]-2-methylacrylamide (3 b), N-{10-[4-(4′,5′-dihydrooxazol-2-yl)phenylcarbamoyl]decyl}-2-acrylamide (5 a), N-{10-[4-(4′,5′-dihydrooxazol-2-yl)phenylcarbamoyl]decyl}-2-methylacrylamide (5 b) and N-[4-(4′,5′-dihydrooxazol-2-yl)-phenyl]-4-vinylbenzamide (7) is described. With an equimolar amount of 2,6-dimethyl-β-cyclodextrin (DMCD) these monomers formed hydrophilic inclusion complexes 3 a,b-DMCD, 5 a,b-DMCD and 7-DMCD. These complexes were polymerized radically in an aqueous medium. Resulting polymers P-(3 a, b), P-(5 a, b) and P-(7) pre…

chemistry.chemical_classificationMaterials sciencePolymers and PlasticsCyclodextrinOrganic ChemistryRadical polymerizationCationic polymerizationOxazolineRing-opening polymerizationInclusion compoundchemistry.chemical_compoundMonomerchemistryPolymerizationPolymer chemistryMaterials ChemistryMacromolecular Rapid Communications
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1976

chemistry.chemical_classificationchemistryPolymerizationPolymer chemistryOrganic chemistryPolymerDie Makromolekulare Chemie
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Macromol. Rapid Commun. 24/2010

2010

Polymers and PlasticsPolymer scienceChemistryOrganic ChemistryMaterials ChemistryNanotechnologyMacromolecular Rapid Communications
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Cyclodextrins in Polymer Synthesis:  Free Radical Polymerization of a N-Methacryloyl-11-aminoundecanoic Acid/β-Cyclodextrin Pseudorotaxane in an Aque…

1999

The relatively hydrophobic monomer N-methacryloyl-11-aminoundecanoic acid (1) was incorporated as a guest into the cavity of β-cyclodextrin (β-CD) as a host, yielding the water-soluble monomer N-me...

chemistry.chemical_classificationRotaxanePolymers and PlasticsAqueous mediumCyclodextrinOrganic ChemistryRadical polymerizationSolution polymerizationmacromolecular substancesPolymerPolyelectrolyteInorganic Chemistrychemistry.chemical_compoundMonomerchemistryPolymer chemistryMaterials ChemistryOrganic chemistryMacromolecules
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Polymerizable ring-shaped molecules containing aspartic acid: synthesis and free radical polymerization of a macrocycle derived from (N'-methacryloyl…

1999

A novel polymerizable macrocycle, 6, was prepared using high dilution techniques. Starting from N-(N'-methacryloyl-11-aminoundecanoyl)-L-aspartic acid dimethyl ester (2), N-(N'methacryloyl-11-aminoundecanoyl)-α,β-bis( 4,9-dioxadodecane-1,12-diamine)-L-aspartic acid amide (4) was obtained via amino-lysis with the bifunctional amine 4,9-dioxadodecane-1,12-diamine (3) in high excess. Addition of the free amino groups to toluene-2,4-diisocyanate (5) under high dilution provided macrocycle 6. The existence and purity of 6 were confirmed by mass spectrometry, NMR and IR spectroscopy, and HPLC. The methacrylic function was used to build up oligomers by free radical polymerization, using AIBN as an…

Polymers and PlasticsGeneral Chemical EngineeringRadical polymerizationGeneral ChemistryToluenechemistry.chemical_compoundLiving free-radical polymerizationEnd-groupchemistryPolymerizationDiamineAmidePolymer chemistryMaterials ChemistryOrganic chemistryBifunctionalDesigned Monomers and Polymers
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