@article{Hartlieb2022, author = {Hartlieb, Matthias}, title = {Photo-iniferter RAFT polymerization}, series = {Macromolecular rapid communications : publishing the newsletters of the European Polymer Federation}, volume = {43}, journal = {Macromolecular rapid communications : publishing the newsletters of the European Polymer Federation}, number = {1}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1521-3927}, doi = {10.1002/marc.202100514}, pages = {25}, year = {2022}, abstract = {Light-mediated polymerization techniques offer distinct advantages over polymerization reactions fueled by thermal energy, such as high spatial and temporal control as well as the possibility to work under mild reaction conditions. Reversible addition-fragmentation chain-transfer (RAFT) polymerization is a highly versatile radical polymerization method that can be utilized to control a variety of monomers and produce a vast number of complex macromolecular structures. The use of light to drive a RAFT-polymerization is possible via multiple routes. Besides the use of photo-initiators, or photo-catalysts, the direct activation of the chain transfer agent controlling the RAFT process in a photo-iniferter (PI) process is an elegant way to initiate and control polymerization reactions. Within this review, PI-RAFT polymerization and its advantages over the conventional RAFT process are discussed in detail.}, language = {en} } @article{JelicicYasinBeuermann2011, author = {Jelicic, Aleksandra and Yasin, Muttaqin and Beuermann, Sabine}, title = {Toward the description and prediction of solvent induced variations in Methacrylate Propagation Rate Coefficients on the basis of Solvatochromic Parameters}, series = {Macromolecular reaction engineering}, volume = {5}, journal = {Macromolecular reaction engineering}, number = {5-6}, publisher = {Wiley-Blackwell}, address = {Malden}, issn = {1862-832X}, doi = {10.1002/mren.201000058}, pages = {232 -- 242}, year = {2011}, abstract = {Benzyl methacrylate (BzMA) propagation rate coefficients, k(p), were determined in ionic liquids and common organic solvents via pulsed-laser polymerizations with subsequent polymer analysis by size-exclusion chromatography (PLP-SEC). The aim of the work is to gain a deeper understanding of the solvent influence on k(p) and to develop a general correlation between solvent-induced variations in k(p) and solvent properties. Applying a linear solvation energy relationship (LSER), which correlates k(p) to solvent solvatochromic parameters, suggests that dipolarity/polarizability determines the solvent influence on k(p). To compare the solvent influence on BzMA k(p) with data for methyl methacrylate, hydroxypropyl methacrylate, and 2-ethoxyethyl methacrylate normalized k(p) data were treated by a single LSER, providing a universal treatment of the solvent influence on the propagation kinetics of the four monomers. Further, the predictive capabilities of this universal correlation were tested with additional monomers from the methacrylate family.}, language = {en} } @article{FechnerKoetz2011, author = {Fechner, Mabya and Koetz, Joachim}, title = {Potentiometric behavior of Polyampholytes based on N,N'-diallyl-N,N'-dimethylammonium chloride and maleamic acid derivatives}, series = {Macromolecular chemistry and physics}, volume = {212}, journal = {Macromolecular chemistry and physics}, number = {24}, publisher = {Wiley-Blackwell}, address = {Malden}, issn = {1022-1352}, doi = {10.1002/macp.201100532}, pages = {2691 -- 2699}, year = {2011}, abstract = {Strongly alternating copolymers (PalH, PalPh, PalPhBisCarb) composed of N,N'-diallyl-N,N'-dimethyl-ammonium chloride (DADMAC) and maleamic acid derivatives (MAD) are synthesized by a water-based free radical copolymerization using 4,4-azobis(4-cyanovaleric acid) (V501) as the initiator. The structure of the copolymers is verified by 1H-NMR, elemental analysis, and thermogravimetric measurements, and the physicochemical properties are investigated by viscometric and potentiometric techniques. Potentiometric titration curves show that the acidity of the carboxylic groups strongly depends on the degree of dissociation and the ionic strength. Since all copolymers behave as polycations at low degree of dissociation, a transition from an extended chain to a coil conformation can be identified by reaching the isoelectric point (IEP).}, language = {en} } @article{HerfurthVollBulleretal.2012, author = {Herfurth, Christoph and Voll, Dominik and Buller, Jens and Weiss, Jan and Barner-Kowollik, Christopher and Laschewsky, Andr{\´e}}, title = {Radical addition fragmentation chain transfer (RAFT) polymerization of ferrocenyl (meth)acrylates}, series = {Journal of polymer science : A, Polymer chemistry}, volume = {50}, journal = {Journal of polymer science : A, Polymer chemistry}, number = {1}, publisher = {Wiley-Blackwell}, address = {Malden}, issn = {0887-624X}, doi = {10.1002/pola.24994}, pages = {108 -- 118}, year = {2012}, abstract = {We report on the controlled free radical homopolymerization of 1-ferrocenylethyl acrylate as well as of three new ferrocene bearing monomers, namely 4-ferrocenylbutyl acrylate, 2-ferrocenylamido-2-methylpropyl acrylate, and 4-ferrocenylbutyl methacrylate, by the RAFT technique. For comparison, the latter monomer was polymerized using ATRP, too. The ferrocene containing monomers were found to be less reactive than their analogues free of ferrocene. The reasons for the low polymerizability are not entirely clear. As the addition of free ferrocene to the reaction mixture did not notably affect the polymerizations, sterical hindrance by the bulky ferrocene moiety fixed on the monomers seems to be the most probable explanation. Molar masses found for 1-ferrocenylethyl acrylate did not exceed 10,000 g mol(-1), while for 4-ferrocenylbutyl (meth) acrylate molar masses of 15,000 g mol(-1) could be obtained. With PDIs as low as 1.3 in RAFT polymerization of the monomers, good control over the polymerization was achieved.}, language = {en} } @article{BarthSiegmannBeuermannetal.2012, author = {Barth, Johannes and Siegmann, Rebekka and Beuermann, Sabine and Russell, Gregory T. and Buback, Michael}, title = {Investigations into chain-length-dependent termination in bulk radical polymerization of 1H, 1H, 2H, 2H-Tridecafluorooctyl methacrylate}, series = {Macromolecular chemistry and physics}, volume = {213}, journal = {Macromolecular chemistry and physics}, number = {1}, publisher = {Wiley-Blackwell}, address = {Malden}, issn = {1022-1352}, doi = {10.1002/macp.201100479}, pages = {19 -- 28}, year = {2012}, abstract = {The SP-PLP-EPR technique is used to carry out a detailed investigation of the radical termination kinetics of 1H, 1H, 2H, 2H-tridecafluorooctyl methacrylate (TDFOMA) in bulk at relatively low conversion. Composite-model behavior for chain-length-dependent termination rate coefficients, kti,i, is observed. It is found that for TDFOMA, ic approximate to 60 independent of temperature, and as approximate to 0.65 and al approximate to 0.2 at 80 degrees C and above. However, at lower temperatures the situation is strikingly different, with the significantly higher average values of as = 0.89 +/- 0.15 and al = 0.32 +/- 0.10 being obtained at 50 degrees C and below. This makes TDFOMA the first monomer to be found that exhibits clearly different exponent values, as and al, at lower and higher temperature, and that has both a high as, like an acrylate, and a high ic, like a methacrylate.}, language = {en} } @article{SiegmannMoellerBeuermann2012, author = {Siegmann, Rebekka and M{\"o}ller, Eleonore and Beuermann, Sabine}, title = {Propagation rate coefficients for homogeneous phase VDF-HFP copolymerization in supercritical CO2}, series = {Macromolecular rapid communications}, volume = {33}, journal = {Macromolecular rapid communications}, number = {14}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1022-1336}, doi = {10.1002/marc.201200115}, pages = {1208 -- 1213}, year = {2012}, abstract = {For the first time, propagation rate coefficients, kp,COPO, for the copolymerizations of vinylidene fluoride and hexafluoropropene have been determined. The kinetic data was determined via pulsed-laser polymerization in conjunction with polymer analysis via size-exclusion chromatography, the PLP-SEC technique. The experiments were carried out in homogeneous phase with supercritical CO2 as solvent for temperatures ranging from 45 to 90 degrees C. Absolute polymer molecular weights were calculated on the basis of experimentally determined MarkHouwink constants. The Arrhenius parameters of kp,COPO vary significantly compared with ethene, which is explained by the high electronegativity of fluorine and less intra- and intermolecular interactions between the partially fluorinated macroradicals.}, language = {en} }