{
  "abstract": "Mechanophore-functionalized polymers enable optical readout of molecular-level stress under macroscopic deformation. Spiropyran (SP)-doped poly(methyl methacrylate) (PMMA) provides a well-established platform for mechanochemical stress sensing, yet molecular stress fields around defined geometric stress concentrators remain largely disconnected from continuum mechanics. To bridge this gap, we develop a geometry-matched molecular dynamics (MD) and finite-element (FE) approach for PMMA containing two opposing semi-elliptical notches of systematically varied depth and width. Molecular simulations employ a hybrid coarse-grained/all-atom (CG/AA) PMMA model with atomistically resolved, quantum-chemically (QC) informed SP, while the FE models use the MD-derived stress–strain response of bulk PMMA as input. Under uniaxial tension, both approaches capture notch-tip stress localization, plastic-zone propagation toward the ligament center, and the characteristic butterfly-shaped stress field. FE simulations reproduce MD notch-tip stresses, demonstrating that suitably parameterized continuum models capture key notch mechanics, whereas defect-mediated rearrangements require molecular resolution. Notch geometry strongly enhances SP activation to its merocyanine (MC) form, lowering the onset strain and localizing activation in highly elongated chains and around deformation-induced voids near the notch edges. These results link defect geometry and molecular stress concentration to mechanophore activation and directly connect molecular and continuum notch mechanics.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 4,
  "authors": [
    {
      "name": "Alexander Dellwisch"
    },
    {
      "name": "Florian Bischoff"
    },
    {
      "name": "Lucio Colombi Ciacchi"
    },
    {
      "name": "Tim Neudecker"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/fhmvxy88spt4g.bib",
  "cited_by": 0,
  "doi": "10.26434/chemrxiv.15010613/v1",
  "fulltext_url": null,
  "id": "fhmvxy88spt4g",
  "issns": [],
  "landing_url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15010613/v1",
  "language": null,
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "2507|Polymer composites and self-healing"
    ]
  ],
  "openalex": "W7222441365",
  "pdf_url": null,
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-16",
  "publisher": "American Chemical Society (ACS)",
  "ris": "https://research.draconitic.com/paper/fhmvxy88spt4g.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:24Z",
      "native_id": "10.26434/chemrxiv.15010613",
      "source": "chemrxiv",
      "url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15010613/v1"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "openalex:2507|Polymer composites and self-healing",
      "subfield": "materials-polymers"
    }
  ],
  "title": "From Notch-Tip Stress to Mechanophore Activation - A Multiscale Study of Mechanochromic PMMA",
  "title_text": "From Notch-Tip Stress to Mechanophore Activation - A Multiscale Study of Mechanochromic PMMA",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:24Z",
  "url": "https://research.draconitic.com/paper/fhmvxy88spt4g",
  "venue": "ChemRxiv",
  "versions": []
}