A Molecular Rationale of Shock Absorption and Self‐Healing in a Biomimetic Apatite–Collagen Composite under Mechanical Load

Shearing in a Biomimetic Apatite-Protein Composite: Molecular Dynamics of Slip Zone Formation, Plastic Flow and Backcreep Mechanisms

“…This observation is in good analogy to the inset of plasticity under full simulation cell compression along the c-axis as reported in ref. [5] . The key finding of the present study is shown at the lower row of figure 1 (d–f).…”

“…On the modeling and simulation side, which shall also be in the focus of the present work, the interplay of ion association to collagen, nucleation of crystalline motifs and mechanisms of self-organization leading to the formation of hierachical composites have been elaborated [3] . Based on this knowledge, scale-up models allow the investigation of the bulk composite and helped to – at least qualitatively – understand aspects of elastic and plastic deformation [4] , [5] .…”

“…For the rationalization of such protein-crystal interface based slip mechanisms at the molecular scale, it is inevitable to take use of simplified models which however must still be able to provide a qualitative account of the underlying phenomena. For simple compression along the c-axis, our recently developed hierarchical apatite-collagen molecular model proved capable of unraveling elastic and plastic deformation mechanisms, including self-healing after releasing mechanical stress [5] . In what follows, we use a considerably larger version of this model to explore shearing and the role of collagen during deformation and relaxation mechanisms.…”

Molecular Simulation of Fundamental Processes in Nanoparticle - Polymer - Nanoparticle Systems Under Tensile Load

“…While more details are described in ref. [5], the key concept is given by placing molecules at random orientation and random position above the nanoparticle surface, and exploring relaxation from molecular dynamics simulation. This procedure was applied iteratively, thus adding surfactant molecules one-by-one until electrostatic repulsion prohibits further association.…”

“…While the former accounts for enamel hardness, resilience is attributed to the composite character resulting from the organic-inorganic interfaces [2]- [4]. The molecular mechanisms that lead to the remarkable resilience of enamel are not fully understood, though molecular dynamics simulations dedicated to biomimetic models of reduced complexity shed some light into fundamental processes occurring under mechanical loading [5]. From this, the organic-inorganic interface was found to facilitate plastic deformation by allowing gradually increasing ionic disorder.…”