eprintid: 33963
rev_number: 15
eprint_status: archive
userid: 7723
dir: disk0/00/03/39/63
datestamp: 2023-11-13 13:30:16
lastmod: 2023-11-22 08:45:12
status_changed: 2023-11-13 13:30:16
type: doctoralThesis
metadata_visibility: show
creators_name: Rennekamp, Benedikt
title: Multi-Scale Simulations of Collagen Failure and Mechanoradicals
subjects: ddc-530
divisions: i-130001
divisions: i-708000
divisions: i-999906
adv_faculty: af-13
cterms_swd: Molekulardynamik
cterms_swd: Kollagen
abstract: Collagen, the most abundant protein in the human body, must withstand high mechanical loads due to its structural role in tendons, skin, bones, and other connective tissue. It was recently found that tensed collagen creates mechanoradicals by homolytic bond scission in the sub-failure regime. The locations and types of initial rupture sites critically decide on both the mechanical and chemical impact of these micro-ruptures on the tissue, but are yet to be explored. 
We here employ hybrid scale-bridging simulations to determine these first breakage points in collagen, combining existing and newly developed methods tailored towards
collagen’s hierarchical structure. We improved our Kinetic Monte Carlo/Molecular Dynamics scheme to simulate bond scissions at the all-atom level, and also developed a
mesoscopic ultra coarse-grained description of a collagen fibril.
We find collagen crosslinks to rupture first, and identify individual sacrificial bonds in trivalent crosslinks that break preferentially, without compromising structural integrity. Collagen’s weak bonds funnel ruptures such that the potentially harmful mechanoradicals are readily stabilized. Our simulations further suggest the length of helices between pairs of crosslinks to determine the trade-off between overall strength and breakage specificity. The combined results suggest this unique failure mode of collagen to be tailored towards combatting an early onset of macroscopic failure and material ageing.
date: 2023
id_scheme: DOI
id_number: 10.11588/heidok.00033963
ppn_swb: 1870849264
own_urn: urn:nbn:de:bsz:16-heidok-339634
date_accepted: 2023-11-07
advisor: HASH(0x55fc36bc71a0)
language: eng
bibsort: RENNEKAMPBMULTISCALE20231107
full_text_status: public
place_of_pub: Heidelberg
citation:   Rennekamp, Benedikt  (2023) Multi-Scale Simulations of Collagen Failure and Mechanoradicals.  [Dissertation]     
document_url: https://archiv.ub.uni-heidelberg.de/volltextserver/33963/1/thesis_signed_newdate.pdf