Buback, Michael M.

[["dc.bibliographiccitation.firstpage","1386"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","Macromolecules"],["dc.bibliographiccitation.lastpage","1393"],["dc.bibliographiccitation.volume","50"],["dc.contributor.author","Kattner, Hendrik"],["dc.contributor.author","Drawe, Patrick"],["dc.contributor.author","Buback, Michael"],["dc.date.accessioned","2018-11-07T10:27:10Z"],["dc.date.available","2018-11-07T10:27:10Z"],["dc.date.issued","2017"],["dc.description.abstract","Via the single pulse-pulsed laser polymerization-electron paramagnetic resonance (SP-PLP-EPR) technique, the chain-length-dependent termination of 5 and 10 wt % sodium methacrylate (NaMAA) in aqueous solution was measured from 5 to 60 degrees C. The rate coefficients k(t)(i,i) for termination of two ionized radicals of identical size i were analyzed by the composite model. Three out of the four composite-model parameters behave similarly to nonionized monomers, whereas the fourth parameter, the rate coefficient for termination of two radicals of chain length unity, k(t)(1,1), exhibits a distinctly different behavior. The temperature dependence of k(t)(1,1) is significantly below the one of fluidity (inverse solution viscosity). Moreover, absolute k(t)(1,1) increases with NaMAA concentration, i.e., toward higher viscosity. Both observations indicate that the termination kinetics of ionized radicals largely differs from the Smoluchowski-type behavior."],["dc.description.sponsorship","Deutsche Forschungsgemeinschaft"],["dc.identifier.doi","10.1021/acs.macromol.6b02641"],["dc.identifier.isi","000395358500011"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/43195"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","PUB_WoS_Import"],["dc.publisher","Amer Chemical Soc"],["dc.relation.issn","1520-5835"],["dc.relation.issn","0024-9297"],["dc.title","Chain-Length-Dependent Termination of Sodium Methacrylate Polymerization in Aqueous Solution Studied by SP-PLP-EPR"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","4160"],["dc.bibliographiccitation.issue","11"],["dc.bibliographiccitation.journal","Macromolecules"],["dc.bibliographiccitation.lastpage","4168"],["dc.bibliographiccitation.volume","50"],["dc.contributor.author","Kattner, Hendrik"],["dc.contributor.author","Buback, Michael"],["dc.date.accessioned","2018-11-07T10:22:43Z"],["dc.date.available","2018-11-07T10:22:43Z"],["dc.date.issued","2017"],["dc.description.abstract","The SP-PLP EPR (single pulse pulsed laser polymerization electron paramagnetic resonance) method has been used to measure the rate coefficients of termination, intramolecular transfer, and propagation for the radical polymerization of 20 wt % trimethylaminoethyl acrylate chloride (TMAEA) in the temperature range 0-90 degrees C. The high complexity of this acrylate system is due to water being the solvent, to the monomer being a strong electrolyte, and to both secondary chain-end radicals and tertiary midchain radicals being simultaneously present. The termination kinetics, which was analyzed by a chain-length-dependent scheme, largely differs from the situation met with nonionized radicals. The reliability of the rate coefficients obtained from the SP-PLP-EPR experiments has been demonstrated by the almost perfect agreement of TMAEA conversion vs time data from simulation, on the basis of these coefficients, and from the chemically initiated TMAEA polymerization experiment at 70 degrees C."],["dc.description.sponsorship","Deutsche Forschungsgemeinschaft; BASF SE"],["dc.identifier.doi","10.1021/acs.macromol.7b00328"],["dc.identifier.isi","000403530400007"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/42325"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","PUB_WoS_Import"],["dc.publisher","Amer Chemical Soc"],["dc.relation.issn","1520-5835"],["dc.relation.issn","0024-9297"],["dc.title","Termination, Transfer, and Propagation Kinetics of Trimethylaminoethyl Acrylate Chloride Radical Polymerization in Aqueous Solution"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","e1939452"],["dc.bibliographiccitation.journal","Molecular Physics"],["dc.contributor.author","Buback, Michael"],["dc.contributor.author","Kattner, Hendrik"],["dc.date.accessioned","2021-07-05T14:57:28Z"],["dc.date.available","2021-07-05T14:57:28Z"],["dc.date.issued","2021"],["dc.identifier.doi","10.1080/00268976.2021.1939452"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/87654"],["dc.language.iso","en"],["dc.notes.intern","DOI-Import GROB-441"],["dc.relation.eissn","1362-3028"],["dc.relation.issn","0026-8976"],["dc.title","Detailed analysis of radical polymerisation kinetics by pulsed-laser techniques "],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","2186"],["dc.bibliographiccitation.issue","24"],["dc.bibliographiccitation.journal","Macromolecular Rapid Communications"],["dc.bibliographiccitation.lastpage","2191"],["dc.bibliographiccitation.volume","36"],["dc.contributor.author","Kattner, Hendrik"],["dc.contributor.author","Buback, Michael"],["dc.date.accessioned","2018-11-07T09:48:00Z"],["dc.date.available","2018-11-07T09:48:00Z"],["dc.date.issued","2015"],["dc.description.abstract","Via electron paramagnetic resonance (EPR) spectroscopy, the type of radicals occurring during acrylamide (AAm) homopolymerization in aqueous solution is investigated between -5 and +100 degrees C. The radicals are produced photochemically under stationary conditions. Midchain AAm radicals (MCRs) are clearly identified by EPR which demonstrates that secondary propagating AAm radicals (SPRs) undergo backbiting reactions. Above 50 degrees C, the fraction of MCRs even exceeds the one of SPRs. The extent of backbiting is however well below the one in butyl acrylate polymerization at identical temperature."],["dc.description.sponsorship","BASF SE; Deutsche Forschungsgemeinschaft"],["dc.identifier.doi","10.1002/marc.201500479"],["dc.identifier.isi","000368033500011"],["dc.identifier.pmid","26487604"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/35221"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Wiley-v C H Verlag Gmbh"],["dc.relation.issn","1521-3927"],["dc.relation.issn","1022-1336"],["dc.title","EPR Study of Backbiting in the Aqueous-Solution Polymerization of Acrylamide"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","2474"],["dc.bibliographiccitation.issue","8"],["dc.bibliographiccitation.journal","Macromolecules"],["dc.bibliographiccitation.lastpage","2480"],["dc.bibliographiccitation.volume","44"],["dc.contributor.author","Meiser, Wibke"],["dc.contributor.author","Barth, Johannes"],["dc.contributor.author","Buback, Michael"],["dc.contributor.author","Kattner, Hendrik"],["dc.contributor.author","Vana, Philipp"],["dc.date.accessioned","2018-11-07T08:56:56Z"],["dc.date.available","2018-11-07T08:56:56Z"],["dc.date.issued","2011"],["dc.description.abstract","The kinetics of reversible addition fragmentation chain transfer (RAFT) polymerization of butyl acrylate with ethyl S-thiobenzoyl-2-thiopropionate (ETTP) as the RAFT agent has been studied. The concentrations of propagating (P-center dot) and intermediate radicals (INT\") were measured via highly time-resolved EPR spectroscopy after initiation by a laser single pulse. Predici simulation of experimental data results in rate coefficients for -40 degrees C of k(ad) = (1.4 +/- 0 4) x 10(6)L mol(-1) s(-1), k(beta) = (4.7 +/- 1.5) s(-1), and k(t)(cross) = 0.25 x k(upsilon), where k(t) is the rate coefficient for termination of two P-center dot species. Fast fragmentation of the intermediate radical is thus observed at this low temperature. Measuring the ratio of INT center dot to P-center dot concentrations during stationary polymerization at -40 and -70 degrees C yields K-eq = k(ad)/k(beta) values of (2.3 +/- 0.6) x 10(5) and 75 +/- 15 L mol(-1), respectively, which correspond to an apparent activation energy difference, E-A(k(ad)/k(beta)), of -49.5 kJ mol(-1)."],["dc.description.sponsorship","Fonds der Chemischen Industrie"],["dc.identifier.doi","10.1021/ma102491x"],["dc.identifier.isi","000289593200013"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/9445"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/23267"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Amer Chemical Soc"],["dc.relation.issn","0024-9297"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","EPR Measurement of Fragmentation Kinetics in Dithiobenzoate-Mediated RAFT Polymerization"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","25"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Macromolecules"],["dc.bibliographiccitation.lastpage","33"],["dc.bibliographiccitation.volume","51"],["dc.contributor.author","Kattner, Hendrik"],["dc.contributor.author","Buback, Michael"],["dc.date.accessioned","2020-12-10T15:22:49Z"],["dc.date.available","2020-12-10T15:22:49Z"],["dc.date.issued","2017"],["dc.identifier.doi","10.1021/acs.macromol.7b02241"],["dc.identifier.eissn","1520-5835"],["dc.identifier.issn","0024-9297"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/73549"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-354"],["dc.title","Termination, Propagation, and Transfer Kinetics of Midchain Radicals in Methyl Acrylate and Dodecyl Acrylate Homopolymerization"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","95"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Macromolecular Reaction Engineering"],["dc.bibliographiccitation.lastpage","107"],["dc.bibliographiccitation.volume","10"],["dc.contributor.author","Wittenberg, Nils F. G."],["dc.contributor.author","Preusser, Calista"],["dc.contributor.author","Kattner, Hendrik"],["dc.contributor.author","Stach, Marek"],["dc.contributor.author","Lacik, Igor"],["dc.contributor.author","Hutchinson, Robin A."],["dc.contributor.author","Buback, Michael"],["dc.date.accessioned","2018-11-07T10:16:03Z"],["dc.date.available","2018-11-07T10:16:03Z"],["dc.date.issued","2016"],["dc.description.abstract","Batch radical polymerization of 5-40wt% non-ionized acrylic acid (AA) in aqueous solution has been studied between 35 and 90 degrees C under variation of initiator concentration and type as well as upon addition of different levels of 2-mercaptoethanol as chain-transfer agent (CTA). Chain-length-dependent termination was taken into account in a model developed to describe the system, as high amounts of CTA have an impact on polymerization kinetics due to reduced chain length. The model also considers the 1,5-hydrogen shift (backbiting) reaction that transforms the secondary propagating radical into a tertiary midchain radical, with the backbiting reaction quantified via C-13 NMR. The model developed is the most comprehensive treatment to date of this complex polymerization system and is able to represent monomer conversion profiles and polymer molar mass distributions over a wide range of conditions."],["dc.identifier.doi","10.1002/mren.201500017"],["dc.identifier.isi","000374562200001"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/40956"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Wiley-v C H Verlag Gmbh"],["dc.relation.issn","1862-8338"],["dc.relation.issn","1862-832X"],["dc.title","Modeling Acrylic Acid Radical Polymerization in Aqueous Solution"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","7410"],["dc.bibliographiccitation.issue","20"],["dc.bibliographiccitation.journal","Macromolecules"],["dc.bibliographiccitation.lastpage","7419"],["dc.bibliographiccitation.volume","48"],["dc.contributor.author","Kattner, Hendrik"],["dc.contributor.author","Buback, Michael"],["dc.date.accessioned","2018-11-07T09:50:01Z"],["dc.date.available","2018-11-07T09:50:01Z"],["dc.date.issued","2015"],["dc.description.abstract","The single pulse pulsed laser polymerization electron paramagnetic resonance (SP-PLP-EPR) method affords the detailed kinetic analysis of acrylamide polymerization in aqueous solution. Highly time-resolved SP-PLP-EPR experiments for 10 and 20 wt % AAm were first carried out at -5 degrees C, where only secondary propagating radicals (SPRs) occur. In a second step, the time evolution of midchain radicals (MCRs), produced from SPRs by backbiting, was measured at higher temperatures. The termination kinetics, including chain-length dependent termination of SPRs, the backbiting rate of SPRs, and the propagation rate of MCRs were determined. The rate coefficients from SP PLP-EPR in conjunction with the known propagation rate coefficient of SPRs, enable the simulation of the kinetics and product properties of AAm radical polymerizations in aqueous solution."],["dc.description.sponsorship","Deutsche Forschungsgemeinschaft; BASF SE"],["dc.identifier.doi","10.1021/acs.macromol.5b01921"],["dc.identifier.isi","000363914000003"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/35621"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Amer Chemical Soc"],["dc.relation.issn","1520-5835"],["dc.relation.issn","0024-9297"],["dc.title","Termination and Transfer Kinetics of Acrylamide Homopolymerization in Aqueous Solution"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1180"],["dc.bibliographiccitation.issue","12"],["dc.bibliographiccitation.journal","Macromolecular Chemistry and Physics"],["dc.bibliographiccitation.lastpage","1191"],["dc.bibliographiccitation.volume","215"],["dc.contributor.author","Kattner, Hendrik"],["dc.contributor.author","Buback, Michael"],["dc.date.accessioned","2018-11-07T09:39:27Z"],["dc.date.available","2018-11-07T09:39:27Z"],["dc.date.issued","2014"],["dc.description.abstract","Bulk homopolymerizations of vinyl acetate and vinyl pivalate are studied by EPR experiments between -65 degrees C and 60 degrees C with dicumyl peroxide acting as the photoinitiator. No midchain radicals are seen, which demonstrates that backbiting plays no role. The chain-length dependence of the termination rate coefficients measured up to 13% monomer conversion is adequately represented by the composite model. The power-law exponents alpha(s) and alpha(l) for short-chain and long-chain radicals are: alpha(s)(VAc) = 0.57 +/- 0.05, alpha(s)(VPi) = 0.67 +/- 0.15, alpha(l) (VAc) = 0.16 +/- 0.07, and alpha(l) (VPi) = 0.16 +/- 0.07. The crossover chain lengths differ largely: i(c) (VAc) = 20 +/- 10 and i(c) (VPi) = 110 +/- 30. The rate coefficient for termination of two radicals of chain length unity, k(t)(1,1), which is the fourth composite-model parameter, depends on temperature, as does the monomer fluidity."],["dc.identifier.doi","10.1002/macp.201400095"],["dc.identifier.isi","000337627000002"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/33284"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Wiley-v C H Verlag Gmbh"],["dc.relation.issn","1521-3935"],["dc.relation.issn","1022-1352"],["dc.title","Chain-Length-Dependent Termination of Vinyl Acetate and Vinyl Pivalate Bulk Homopolymerizations Studied by SP-PLP-EPR"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","5308"],["dc.bibliographiccitation.issue","14"],["dc.bibliographiccitation.journal","Macromolecules"],["dc.bibliographiccitation.lastpage","5314"],["dc.bibliographiccitation.volume","50"],["dc.contributor.author","Kattner, Hendrik"],["dc.contributor.author","Buback, Michael"],["dc.date.accessioned","2020-12-10T15:22:49Z"],["dc.date.available","2020-12-10T15:22:49Z"],["dc.date.issued","2017"],["dc.identifier.doi","10.1021/acs.macromol.7b00745"],["dc.identifier.eissn","1520-5835"],["dc.identifier.issn","0024-9297"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/73546"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-354"],["dc.title","Chain-Length-Dependent Termination of Styrene Bulk Polymerization up to High Degrees of Monomer Conversion"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]