0000000000593921

AUTHOR

Markus Gerle

showing 3 related works from this author

MALDI-TOF characterization of macromonomers

1996

Methacryloyl endfunctionalized oligostyrene macromonomers were characterized by matrix assisted laser desorption ionization/time of flight (MALDI-TOF) spectroscopy and by isocratic and gradient high performance liquid chromatography (HPLC). The molar mass distribution derived by the different techniques coincide for the investigated oligomers. Mixing experiments revealed that the MALDI-TOF peak areas do not necessarily represent the mixing ratio of the components. Combination of gradient HPLC and MALDI-TOF has resolved the chemical composition of the coupling products formed by reaction of the living anion with oxygen.

ChromatographyPolymers and PlasticsChemistryOrganic ChemistryMatrix isolationAnalytical chemistryMass spectrometryMacromonomerHigh-performance liquid chromatographyTime of flightMatrix-assisted laser desorption/ionizationMaterials ChemistryMolar mass distributionSpectroscopyMacromolecular Rapid Communications
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Main Chain Conformation and Anomalous Elution Behavior of Cylindrical Brushes As Revealed by GPC/MALLS, Light Scattering, and SFM

1999

High molar mass polymacromonomers based on methacryloyl end-functionalized oligo methacrylates (Mn = 2410 g/mol) adopt the conformation of wormlike cylindrical brushes. Comparison of the absolute molar mass, Mw, determined by static light scattering and the contour length, Lw, of the molecules measured by SFM in the dry state revealed the length per vinylic main chain monomer of the cylindrical structure to be less than 0.1 nm, thus being much shorter than the maximum value of 0.25 nm. In solution this shrinkage could be quantified to 0.071 nm per monomer by Holtzer analysis of the scattering curves which in addition yielded the Kuhn statistical segment length lk = 120 nm. GPC MALLS investi…

Molar massChromatographyPolymers and PlasticsElutionChemistryOrganic ChemistryAnalytical chemistryLight scatteringInorganic ChemistryGel permeation chromatographyAbsolute molar masschemistry.chemical_compoundMonomerMaterials ChemistryRadius of gyrationStatic light scatteringMacromolecules
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Wormlike Polystyrene Brushes in Thin Films

1997

Mono- and multilayer films were prepared on mica by solution casting of a high molecular weight polymacromonomer, i.e., a polymethacrylate of about 1000 repeating units each of which was substituted by a polystyrene chain with a molecular weight of about 5000 Da. The films were studied by tapping scanning force microscopy. The material showed a remarkable preference for forming well-defined monolayers of a thickness of 6.5 ± 0.2 nm consistent with the hard core diameter of the collapsed cylindrical brush molecules. When the films were probed with high normal force, the single molecules were observed to organize in a dense nematic-like packing as expected for inherently stiff molecules. In o…

Normal forceMaterials scienceSurfaces and InterfacesSubstrate (electronics)Condensed Matter PhysicsCastingchemistry.chemical_compoundchemistryMonolayerPolymer chemistryElectrochemistryMoleculeGeneral Materials SciencePolystyreneMicaComposite materialThin filmSpectroscopyLangmuir
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