@article{SvaneborgKarimiVarzanehHojdisetal.2016,
  author    = {Svaneborg, Carsten and Karimi-Varzaneh, Hossein Ali and Hojdis, Nils and Fleck, Franz and Everaers, Ralf},
  title     = {Multiscale approach to equilibrating model polymer melts},
  series = {Physical Review E},
  volume    = {94},
  journal   = {Physical Review E},
  number    = {032502},
  publisher = {AIP Publishing},
  address   = {Melville, NY},
  issn      = {2470-0053},
  doi       = {10.1103/PhysRevE.94.032502},
  year      = {2016},
  abstract  = {We present an effective and simple multiscale method for equilibrating Kremer Grest model polymer melts of varying stiffness. In our approach, we progressively equilibrate the melt structure above the tube scale, inside the tube and finally at the monomeric scale. We make use of models designed to be computationally effective at each scale. Density fluctuations in the melt structure above the tube scale are minimized through a Monte Carlo simulated annealing of a lattice polymer model. Subsequently the melt structure below the tube scale is equilibrated via the Rouse dynamics of a force-capped Kremer-Grest model that allows chains to partially interpenetrate. Finally the Kremer-Grest force field is introduced to freeze the topological state and enforce correct monomer packing. We generate 15 melts of 500 chains of 10.000 beads for varying chain stiffness as well as a number of melts with 1.000 chains of 15.000 monomers. To validate the equilibration process we study the time evolution of bulk, collective, and single-chain observables at the monomeric, mesoscopic, and macroscopic length scales. Extension of the present method to longer, branched, or polydisperse chains, and/or larger system sizes is straightforward.},
  language  = {en}
}
@article{SchwabHojdisLacayoetal.2016,
  author    = {Schwab, Lukas and Hojdis, Nils and Lacayo, Jorge and Wilhelm, Manfred},
  title     = {Fourier-Transform Rheology of Unvulcanized, Carbon Black Filled Styrene Butadiene Rubber},
  series = {Macromolecular Materials and Engineering},
  volume    = {301},
  journal   = {Macromolecular Materials and Engineering},
  number    = {4},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1439-2054},
  doi       = {10.1002/mame.201500356},
  pages     = {457 -- 468},
  year      = {2016},
  abstract  = {Rubber materials filled with reinforcing fillers display nonlinear rheological behavior at small strain amplitudes below γ0 < 0.1. Nevertheless, rheological data are analyzed mostly in terms of linear parameters, such as shear moduli (G′, G″), which loose their physical meaning in the nonlinear regime. In this work styrene butadiene rubber filled with carbon black (CB) under large amplitude oscillatory shear (LAOS) is analyzed in terms of the nonlinear parameter I3/1. Three different CB grades are used and the filler load is varied between 0 and 70 phr. It is found that I3/1(φ) is most sensitive to changes of the total accessible filler surface area at low strain amplitudes (γ0 = 0.32). The addition of up to 70 phr CB leads to an increase of I3/1(φ) by a factor of more than ten. The influence of the measurement temperature on I3/1 is pronounced for CB levels above the percolation threshold.},
  language  = {en}
}
@article{HarishWriggersJungketal.2016,
  author    = {Harish, Ajay B. and Wriggers, Peter and Jungk, Juliane and Hojdis, Nils and Recker, Carla},
  title     = {Mesoscale Constitutive Modeling of Non-Crystallizing Filled Elastomers},
  series = {Computational Mechanics},
  volume    = {57},
  journal   = {Computational Mechanics},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1432-0924},
  doi       = {10.1007/s00466-015-1251-1},
  pages     = {653 -- 677},
  year      = {2016},
  abstract  = {Elastomers are exceptional materials owing to their ability to undergo large deformations before failure. However, due to their very low stiffness, they are not always suitable for industrial applications. Addition of filler particles provides reinforcing effects and thus enhances the material properties that render them more versatile for applications like tyres etc. However, deformation behavior of filled polymers is accompanied by several nonlinear effects like Mullins and Payne effect. To this day, the physical and chemical changes resulting in such nonlinear effect remain an active area of research. In this work, we develop a heterogeneous (or multiphase) constitutive model at the mesoscale explicitly considering filler particle aggregates, elastomeric matrix and their mechanical interaction through an approximate interface layer. The developed constitutive model is used to demonstrate cluster breakage, also, as one of the possible sources for Mullins effect observed in non-crystallizing filled elastomers.},
  language  = {en}
}
@inproceedings{SauerbornLiebenstundRaueetal.2017,
  author    = {Sauerborn, Markus and Liebenstund, Lena and Raue, Markus and Mang, Thomas and Herrmann, Ulf and Dueing, Andreas},
  title     = {Analytic method for material aging and quality analyzing to forecast long time stability of plastic micro heliostat components},
  series = {AIP Conference Proceedings},
  volume    = {1850},
  booktitle = {AIP Conference Proceedings},
  number    = {1},
  doi       = {10.1063/1.4984388},
  pages     = {030045-1 -- 030045-8},
  year      = {2017},
  language  = {en}
}
@article{BreuerMangSchoeningetal.2017,
  author    = {Breuer, Lars and Mang, Thomas and Sch{\"o}ning, Michael Josef and Thoelen, Ronald and Wagner, Torsten},
  title     = {Investigation of the spatial resolution of a laser-based stimulation process for light-addressable hydrogels with incorporated graphene oxide by means of IR thermography},
  series = {Sensors and Actuators A: Physical},
  volume    = {268},
  journal   = {Sensors and Actuators A: Physical},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0924-4247},
  doi       = {10.1016/j.sna.2017.11.031},
  pages     = {126 -- 132},
  year      = {2017},
  language  = {en}
}
@article{MeyerHentschkeHageretal.2017,
  author    = {Meyer, Jan and Hentschke, Reinhard and Hager, Jonathan and Hojdis, Nils and Karimi-Varzaneh, Hossein Ali},
  title     = {Molecular Simulation of Viscous Dissipation due to Cyclic Deformation of a Silica-Silica Contact in Filled Rubber},
  series = {Macromolecules},
  volume    = {50},
  journal   = {Macromolecules},
  number    = {17},
  issn      = {1520-5835},
  doi       = {10.1021/acs.macromol.7b00947},
  pages     = {6679 -- 6689},
  year      = {2017},
  language  = {en}
}
@article{MayerHentschkeHageretal.2017,
  author    = {Mayer, Jan and Hentschke, Reinhard and Hager, Jonathan and Hojdis, Nils and Karimi-Varnaneh, Hossein Ali},
  title     = {A Nano-Mechanical Instability as Primary Contribution to Rolling Resistance},
  series = {Scientific Reports},
  volume    = {7},
  journal   = {Scientific Reports},
  number    = {Article number 11275},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {2045-2322},
  year      = {2017},
  language  = {en}
}
@article{EckertRudolphGuoetal.2018,
  author    = {Eckert, Alexander and Rudolph, Tobias and Guo, Jiaqi and Mang, Thomas and Walther, Andreas},
  title     = {Exceptionally Ductile and Tough Biomimetic Artificial Nacre with Gas Barrier Function},
  series = {Advanced Materials},
  volume    = {30},
  journal   = {Advanced Materials},
  number    = {32},
  publisher = {Wiley-VCH},
  doi       = {10.1002/adma.201802477},
  pages     = {Article number 1802477},
  year      = {2018},
  abstract  = {Synthetic mimics of natural high-performance structural materials have shown great and partly unforeseen opportunities for the design of multifunctional materials. For nacre-mimetic nanocomposites, it has remained extraordinarily challenging to make ductile materials with high stretchability at high fractions of reinforcements, which is however of crucial importance for flexible barrier materials. Here, highly ductile and tough nacre-mimetic nanocomposites are presented, by implementing weak, but many hydrogen bonds in a ternary nacre-mimetic system consisting of two polymers (poly(vinyl amine) and poly(vinyl alcohol)) and natural nanoclay (montmorillonite) to provide efficient energy dissipation and slippage at high nanoclay content (50 wt\%). Tailored interactions enable exceptional combinations of ductility (close to 50\% strain) and toughness (up to 27.5 MJ m⁻³). Extensive stress whitening, a clear sign of high internal dynamics at high internal cohesion, can be observed during mechanical deformation, and the materials can be folded like paper into origami planes without fracture. Overall, the new levels of ductility and toughness are unprecedented in highly reinforced bioinspired nanocomposites and are of critical importance to future applications, e.g., as barrier materials needed for encapsulation and as a printing substrate for flexible organic electronics.},
  language  = {en}
}
@article{SvaneborgKarimiVarzanehHojdisetal.2018,
  author    = {Svaneborg, Carsten and Karimi-Varzaneh, Hossein Ali and Hojdis, Nils and Fleck, Franz and Everaers, Ralf},
  title     = {Kremer-Grest Models for Universal Properties of Specific Common Polymer Species},
  series = {Soft Condensed Matter},
  journal   = {Soft Condensed Matter},
  number    = {1606.05008},
  year      = {2018},
  abstract  = {The Kremer-Grest (KG) bead-spring model is a near standard in Molecular Dynamic simulations of generic polymer properties. It owes its popularity to its computational efficiency, rather than its ability to represent specific polymer species and conditions. Here we investigate how to adapt the model to match the universal properties of a wide range of chemical polymers species. For this purpose we vary a single parameter originally introduced by Faller and M{\"u}ller-Plathe, the chain stiffness. Examples include polystyrene, polyethylene, polypropylene, cis-polyisoprene, polydimethylsiloxane, polyethyleneoxide and styrene-butadiene rubber. We do this by matching the number of Kuhn segments per chain and the number of Kuhn segments per cubic Kuhn volume for the polymer species and for the Kremer-Grest model. We also derive mapping relations for converting KG model units back to physical units, in particular we obtain the entanglement time for the KG model as function of stiffness allowing for a time mapping. To test these relations, we generate large equilibrated well entangled polymer melts, and measure the entanglement moduli using a static primitive-path analysis of the entangled melt structure as well as by simulations of step-strain deformation of the model melts. The obtained moduli for our model polymer melts are in good agreement with the experimentally expected moduli.},
  language  = {en}
}
@article{Delaittre2019,
  author    = {Delaittre, Guillaume},
  title     = {Telechelic Poly(2-Oxazoline)s},
  series = {European Polymer Journal},
  journal   = {European Polymer Journal},
  number    = {In Press, Journal Pre-proof, 109281},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0014-3057},
  doi       = {10.1016/j.eurpolymj.2019.109281},
  year      = {2019},
  language  = {en}
}