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Buchmeiser M.R.,University of Stuttgart | Buchmeiser M.R.,Institute For Textilchemie Und Chemiefasern Itcf
Macromolecular Chemistry and Physics | Year: 2014

Precision polymers have entered many new areas and allowed for the development of new technological fields, whether on the macro-, meso- or microscale. The Special issue of Macromolecular Chemistry and Physics contains some of the new and exciting developments in the synthesis and properties of precision polymers. A review on (functional) precision olefins with a spatially resolved positioning of functional groups prepared by acyclic diene metathesis (ADMET) polymerization by M. D. Schulz and K. B. Wagener clearly illustrates the potential of this methodology. W. H. Binder and co-workers focus on ADMET polymerization-derived precision polymers containing precisely placed pyridine-2,6-diylbisamide units and their packing in the solid (crystalline) state. K. Nomura and co-workers report on defect-free, oligomeric 2,5-diakoxy-pphenylene vinylenes and their optical properties. The review by B. Rieger and co-workers summarizes and highlights recent developments in the area of rare earth metal-mediated synthesis of homo- and block copolymers, telechelic polymers, and polymer brushes using methyl methyacrylate, vinylphosphanes, 2-oxazolines, or vinylpyridine as monomers. J. F. Lutz and co-workers describe the use of a Rink-amide telechelic poly(styrene) prepared by atom-transfer radical polymerization (ATRP) and its use in the synthesis of a precision tetrapeptide. J. Okuda and co-workers describe the living copolymerization of styrene with butadiene by bis(phenolate)-Zr(IV) complexes to yield well-defined isotactic poly(styrene)-block-poly-(butadiene) copolymers. Source

Buchmeiser M.R.,University of Stuttgart | Buchmeiser M.R.,Institute For Textilchemie Und Chemiefasern Itcf
Macromolecular Symposia | Year: 2010

The chemistry of ring-opening metathesis polymerization- (ROMP) derived monolithic materials is summarized. Since ROMP triggered by well-defined transition metal alkylidenes is a living polymerization method, it allows for the controlled and highly reproducible synthesis of monolithic media in terms of total porosity, pore size distribution and specific surface area. In addition, the high functionality tolerance of ROMP allows for creating monolithic supports with an unprecedented diversity in terms of functional groups that may be introduced. Selected applications in the areas of separation science, heterogeneous catalysis and tissue engineering are presented and discussed within the context of ROMP. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Bandari R.,University of Stuttgart | Kuballa J.,GALAB Laboratories GmbH | Buchmeiser M.R.,University of Stuttgart | Buchmeiser M.R.,Institute For Textilchemie Und Chemiefasern Itcf
Journal of Separation Science | Year: 2013

Lectin-functionalized monolithic columns were prepared within polyether ether ketone (PEEK) columns (150 × 4.6 mm id) via transition metal-catalyzed ring-opening metathesis polymerization of norborn-2-ene (NBE) and trimethylolpropane-tris(5-norbornene-2-carboxylate) (CL) using the first-generation Grubbs initiator RuCl2(PCy3) 2(CHPh) (1, Cy = cyclohexyl) in the presence of a macro- and microporogen, i.e. of 2-propanol and toluene. Postsynthesis functionalization was accomplished via in situ grafting of 2,5-dioxopyrrolidin-1-yl-bicyclo[2.2.1] hept-5-ene-2-carboxylate to the surface of the monoliths followed by reaction with α,ω-diamino-poly(ethyleneglycol). The pore structure of the poly(ethyleneglycol)- derivatized monoliths was investigated by electron microscopy and inverse-size exclusion chromatography, respectively. The amino-poly(ethyleneglycol) functionalized monolithic columns were then successfully used for the immobilization of lectin from Lens culinaris hemagglutinin. The thus prepared lectin-functionalized monoliths were applied to the affinity chromatography-based purification of glucose oxidase. The binding capacity of Lens culinaris hemagglutinin-immobilized monolithic column for glucose oxidase was found to be 2.2 mg/column. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Buchmeiser M.R.,University of Stuttgart | Buchmeiser M.R.,Institute For Textilchemie Und Chemiefasern Itcf | Schmidt C.,Leibniz Institute of Surface Modification | Wang D.,University of Stuttgart
Macromolecular Chemistry and Physics | Year: 2011

4-Aza-1,6-heptadiynes are cyclopolymerized using a series of Schrock- and Grubbs-Hoveyda-type initiators. It is found that with Schrock initiators (i) the concept of large and small alkoxides applies, (ii) the size of the substituents in the 2- and 6-position of the arylimido ligand play a significant role in the mode of insertion, (iii) addition of a base such as quinuclidine to an initiator favors α-insertion and thus five-membered repeat units, and (iv) coordination of the monomer's nitrogen lone pair during the catalytic cycle favors β- over α-insertion and thus results in polymers with a high fraction of six-membered rings. Using modified Grubbs-Hoveyda initiators, cyclopolymerization of the azaheptadiynes lead to the formation of poly(ene)s containing 24-51% six-membered repeat units, thus representing the first Ru-alkylidene-triggered cyclopolymerization of 1,6-heptadiynes with significant β-selectivity. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Sudheendran M.,University of Stuttgart | Buchmeiser M.R.,University of Stuttgart | Buchmeiser M.R.,Institute For Textilchemie Und Chemiefasern Itcf
Macromolecules | Year: 2010

The ring-opening metathesis polymerization (ROMP) of norborn-2-ene (NBE) and cis-cyclo- octene (COE) was initiated with well-defined Grubbs-type initiators, i.e., RuCl 2(CHPh)(PCy 3) 2 (1), [RuCl 2(PCy 3)- (IMesH 2)(CHPh)] (2), and [RuCl 2(3-Br-Py) 2(IMesH 2)(CHPh)] (3)(MesH 2 = 1, 3-bis(2, 4, 6-trimethylphenyl)- imidazolin-2-ylidene, PCy 3 = tricyclohexylphosphine, 3-Br-Py = 3-bromopyridine). Reaction of the living polymers with O 2 (air) resulted in the formation of aldehyde-semitelechelic polymers in up to 80% yield, depending on the initiator and monomer used. To proof aldehyde formation, the terminal aldehyde groups were converted into the corresponding 2, 4-dinitrophenylhydrazine derivatives, and the structure of the hydrazones was confirmed by NMR and IR spectroscopy. This simple methodology was then used for the functionalization of ROMP-derived monoliths prepared from NBE, 1, 4, 4a, 5, 8, 8a-hexahydro-1, 4, 5, 8-exo-endo-dimethanonaphthalene (DMN-H6) and (NBE-CH 2O) 3SiCH 3, to yield aldehyde-funtionalized monoliths. The extent of aldehyde formation was determined by hydrazone formation. Up to 8 μmol of aldehyde groups/g monolith could be generated by this approach. Finally, these aldehyde-functionalized monoliths were used for the immobilization of trypsin. Excellent proteolytic activity of the immobilized enzyme was found both under batch and continuous flow conditions. © 2010 American Chemical Society. Source

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