@article{DebsharmaSchmidtLaschewskyetal.2021,
  author    = {Debsharma, Tapas and Schmidt, Bernd and Laschewsky, Andre and Schlaad, Helmut},
  title     = {Ring-opening metathesis polymerization of unsaturated carbohydrate derivatives},
  series = {Macromolecules : a publication of the American Chemical Society},
  volume    = {54},
  journal   = {Macromolecules : a publication of the American Chemical Society},
  number    = {6},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {0024-9297},
  doi       = {10.1021/acs.macromol.0c02821},
  pages     = {2720 -- 2728},
  year      = {2021},
  abstract  = {A series of biomass-derived levoglucosenyl alkyl ethers (alkyl = methyl, ethyl, n-propyl, isopropyl, and n-butyl) were synthesized and polymerized by ring-opening olefin metathesis polymerization using the Grubbs catalyst C793 at room temperature. Polymerizations were successfully performed in conventional solvents such as 1,4-dioxane and dichloromethane as well as in polar aprotic "green" solvents such as 2-methyltetrahydrofuran, dihydrolevoglucosenone (Cyrene), and ethyl acetate. The prepared polyacetals with degrees of polymerization of similar to 100 exhibit Schulz-Flory-type molar mass distributions and are thermoplastic materials with rather low glass transition temperatures in the range of 43-0 degrees C depending on the length of the alkyl substituent. Kinetic studies revealed that the polymerization proceeded rapidly to a steady state with a certain minimum monomer concentration threshold. When the steady state was reached, just about half of the [Ru] catalyst had been effective to initiate the polymerization, indicating that the initiation step was a slow process. The remaining catalyst was still active and did no longer react with monomers but with in-chain double bonds, cutting the formed polymer chains into shorter fragments. In the long term, all catalyst was consumed and propagating [Ru] chain ends were deactivated by the elimination of [Ru] from the chain ends to form inactive chains with terminal aldehyde groups.},
  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}
}
@article{DebsharmaBehrendtLaschewskyetal.2019,
  author    = {Debsharma, Tapas and Behrendt, Felix Nicolas and Laschewsky, Andre and Schlaad, Helmut},
  title     = {Ring-opening metathesis polymerization of biomass-derived levoglucosenol},
  series = {Angewandte Chemie : a journal of the Gesellschaft Deutscher Chemiker},
  volume    = {58},
  journal   = {Angewandte Chemie : a journal of the Gesellschaft Deutscher Chemiker},
  number    = {20},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1433-7851},
  doi       = {10.1002/anie.201814501},
  pages     = {6718 -- 6721},
  year      = {2019},
  abstract  = {The readily available cellulose-derived bicyclic compound levoglucosenol was polymerized through ring-opening metathesis polymerization (ROMP) to yield polylevoglucosenol as a novel type of biomass-derived thermoplastic polyacetal, which, unlike polysaccharides, contains cyclic as well as linear segments in its main chain. High-molar-mass polyacetals with apparent weight-average molar masses of up to 100kgmol(-1) and dispersities of approximately 2 were produced despite the non-living/controlled character of the polymerization due to irreversible deactivation or termination of the catalyst/active chain ends. The resulting highly functionalized polyacetals are glassy in bulk with a glass transition temperature of around 100 degrees C. In analogy to polysaccharides, polylevoglucosenol degrades slowly in an acidic environment.},
  language  = {en}
}