@article{DasNoackSchlaadetal.2020,
  author    = {Das, Abhijna and Noack, Sebastian and Schlaad, Helmut and Reiter, G{\"u}nter and Reiter, Renate},
  title     = {Exploring pathways to equilibrate Langmuir polymer films},
  series = {Langmuir},
  volume    = {36},
  journal   = {Langmuir},
  number    = {28},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {0743-7463},
  doi       = {10.1021/acs.langmuir.0c01268},
  pages     = {8184 -- 8192},
  year      = {2020},
  abstract  = {Focusing on the phase-coexistence region in Langmuir films of poly(L-lactide), we investigated changes in nonequilibrated morphologies and the corresponding features of the isotherms induced by different experimental pathways of lateral compression and expansion. In this coexistence region, the surface pressure II was larger than the expected equilibrium value and was found to increase upon compression, i.e., exhibited a nonhorizontal plateau. As shown earlier by using microscopic techniques [Langmuir 2019, 35, 6129-6136], in this plateau region, well-ordered mesoscopic clusters coexisted with a surrounding matrix phase. We succeeded in reducing Pi either by slowing down the rate of compression or through increasing the waiting time after stopping the movement of the barriers, which allowed for relaxations in the coexistence region. Intriguingly, the most significant pressure reduction was observed when recompressing a film that had already been compressed and expanded, if the recompression was started from an area value smaller than the one anticipated for the onset of the coexistence region. This observation suggests a "self-seeding" behavior, i.e., pre-existing nuclei allowed to circumvent the nucleation step. The decrease in Pi was accompanied by a transformation of the initially formed metastable mesoscopic clusters into a thermodynamically favored filamentary morphology. Our results demonstrate that it is practically impossible to obtain fully equilibrated coexisting phases in a Langmuir polymer film, neither under conditions of extremely slow continuous compression nor for long waiting times at a constant area in the coexistence region which allow for reorganization.},
  language  = {en}
}
@article{HessSchmidtSchlaad2020,
  author    = {Hess, Andreas and Schmidt, Bernhard Volkmar Konrad Jakob and Schlaad, Helmut},
  title     = {Aminolysis induced functionalization of (RAFT) polymer-dithioester with thiols and disulfides},
  series = {Polymer Chemistry},
  volume    = {11},
  journal   = {Polymer Chemistry},
  number    = {48},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {1759-9954},
  doi       = {10.1039/d0py01365j},
  pages     = {7677 -- 7684},
  year      = {2020},
  abstract  = {A series of polystyrene- and poly(methyl methacrylate)-dithioesters was subjected to aminolysis under ambient atmospheric conditions, i.e., in the presence of oxygen. Polymer disulfide coupling by oxidation occurred within tens of minutes and the yield of disulfide-coupled polymer increased with decreasing polymer molar mass. Oxidation of thiolates is usually an unwanted side reaction, here it is employed to obtain exclusively polymeric mixed disulfides through in situ aminolysis/functionalization in the presence of a thiol. The in situ aminolysis/functionalization in the presence of a disulfide, Ellman's reagent or polymer disulfide, resulted in the exclusive formation of polymer-dithionitrobenzoic acid, which can be further reacted with a thiol to exchange the terminal functionality, or block copolymer with dynamic disulfide linker, respectively.},
  language  = {en}
}
@article{AlNajiSchlaadAntonietti2020,
  author    = {Al-Naji, Majd and Schlaad, Helmut and Antonietti, Markus},
  title     = {New (and old) monomers from biorefineries to make polymer chemistry more sustainable},
  series = {Macromolecular rapid communications},
  volume    = {42},
  journal   = {Macromolecular rapid communications},
  number    = {3},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1022-1336},
  doi       = {10.1002/marc.202000485},
  pages     = {11},
  year      = {2020},
  abstract  = {This opinion article describes recent approaches to use the "biorefinery" concept to lower the carbon footprint of typical mass polymers, by replacing parts of the fossil monomers with similar or even the same monomer made from regrowing dendritic biomass. Herein, the new and green catalytic synthetic routes are for lactic acid (LA), isosorbide (IS), 2,5-furandicarboxylic acid (FDCA), and p-xylene (pXL). Furthermore, the synthesis of two unconventional lignocellulosic biomass derivable monomers, i.e., alpha-methylene-gamma-valerolactone (MeGVL) and levoglucosenol (LG), are presented. All those have the potential to enter in a cost-effective way, also the mass market and thereby recover lost areas for polymer materials. The differences of catalytic unit operations of the biorefinery are also discussed and the challenges that must be addressed along the synthesis path of each monomers.},
  language  = {en}
}
@article{KayaDebsharmaSchlaadetal.2020,
  author    = {Kaya, Kerem and Debsharma, Tapas and Schlaad, Helmut and Yagci, Yusuf},
  title     = {Cellulose-based polyacetals by direct and sensitized photocationic ring-opening polymerization of levoglucosenyl methyl ether},
  series = {Polymer Chemistry},
  volume    = {11},
  journal   = {Polymer Chemistry},
  number    = {43},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {1759-9954},
  doi       = {10.1039/d0py01307b},
  pages     = {6884 -- 6889},
  year      = {2020},
  abstract  = {This study aims to explore the photoinitiated cationic ring-opening polymerization of levoglucosenyl methyl ether (LGME), a chemical obtained from the most abundant biomass - cellulose. Direct and sensitized photopolymerizations of LGME using photoinitiators acting at the near UV or visible range in conjunction with diphenyliodonium hexafluoroantimonate (DPI) yielded unsaturated polyacetals with varying molar masses and distributions.},
  language  = {en}
}
@misc{AlNajiSchlaadAntonietti2020,
  author    = {Al-Naji, Majd and Schlaad, Helmut and Antonietti, Markus},
  title     = {New (and old) monomers from biorefineries to make polymer chemistry more sustainable},
  series = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {3},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-57061},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-570614},
  pages     = {13},
  year      = {2020},
  abstract  = {This opinion article describes recent approaches to use the "biorefinery" concept to lower the carbon footprint of typical mass polymers, by replacing parts of the fossil monomers with similar or even the same monomer made from regrowing dendritic biomass. Herein, the new and green catalytic synthetic routes are for lactic acid (LA), isosorbide (IS), 2,5-furandicarboxylic acid (FDCA), and p-xylene (pXL). Furthermore, the synthesis of two unconventional lignocellulosic biomass derivable monomers, i.e., alpha-methylene-gamma-valerolactone (MeGVL) and levoglucosenol (LG), are presented. All those have the potential to enter in a cost-effective way, also the mass market and thereby recover lost areas for polymer materials. The differences of catalytic unit operations of the biorefinery are also discussed and the challenges that must be addressed along the synthesis path of each monomers.},
  language  = {en}
}
@article{MaticHessSchanzenbachetal.2020,
  author    = {Matic, Aleksandar and Hess, Andreas and Schanzenbach, Dirk and Schlaad, Helmut},
  title     = {Epoxidized 1,4-polymyrcene},
  series = {Polymer chemistry},
  volume    = {11},
  journal   = {Polymer chemistry},
  number    = {7},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {1759-9954},
  doi       = {10.1039/c9py01783f},
  pages     = {1364 -- 1368},
  year      = {2020},
  abstract  = {1,4-Polymyrcene was synthesized by anionic polymerization and epoxidized using meta-chloroperbenzoic acid. Samples with different degrees of epoxidation (25\%, 49\%, 74\%, and 98\%) were prepared and examined according to their chemical and thermal properties. Epoxidation was found to increase the glass transition temperature (T-g = 14 degrees C for the 98\% epoxidized 1,4-polymyrcene) as well as the shelf live (>10 months). The trisubstituted epoxide groups were remarkably stable against nucleophiles under basic conditions but cross-linked or hydrolyzed in the presence of an acid. Also, highly epoxidized 1,4-polymyrcene readily cross-linked upon annealing at 260 degrees C to produce an epoxy resin.},
  language  = {en}
}
@article{GlatzelNoackSchanzenbachetal.2020,
  author    = {Glatzel, Julia and Noack, Sebastian and Schanzenbach, Dirk and Schlaad, Helmut},
  title     = {Anionic polymerization of dienes in 'green' solvents},
  series = {Polymer international},
  volume    = {70},
  journal   = {Polymer international},
  number    = {2},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {0959-8103},
  doi       = {10.1002/pi.6152},
  pages     = {181 -- 184},
  year      = {2020},
  abstract  = {Isoprene and beta-myrcene were polymerized by anionic polymerization in bulk and in the 'green' ether solvents cyclopentyl methyl ether and 2-methyltetrahydrofuran and, for comparison, in cyclohexane and tetrahydrofuran. The polydienes produced in bulk and in cyclohexane contained high amounts of 1,4 units (>90\%) whereas those produced in ether solvents were rich in 1,2 and 3,4 units (36\%-86\%). Comparison of the microstructures and glass transition temperatures of the polydienes obtained in the various solvents suggests that conventionally used solvents can be substituted by environmentally more friendly alternatives.},
  language  = {en}
}