{
  "abstract": "For nearly nine decades, Flory’s equal-reactivity hypothesis has universally underpinned the statistics of step-growth polymerization. However, modern monomers featuring rigid fused-ring architectures or catalytic bond-forming mechanisms routinely violate this core assumption. Consequently, the resulting molecular-weight anomalies have long been erroneously misattributed to side reactions or impurities, obscuring the underlying kinetic reality. Here, we resolve this theoretical blind spot by generalizing the AA + BB polycondensation into a strict analytical framework encompassing a kinetic enhancement parameter (𝛼). By exactly solving the infinitely coupled kinetic network, we derive closed-form expressions for the entire parameter space of stoichiometry (𝑟) and kinetics (𝛼), unveiling three macroscopic laws. First, a Terminal Dichotomy: on the A-deficient side (𝑟 < 1), the reaction undergoes \"kinetic freezing,\" permanently archiving the kinetic 𝛼 -fingerprint within the end-cap inventory; conversely, on the A-excess side (𝑟 > 1 ), the system exhibits \"𝛼 -amnesia,\" where terminal states are dictated solely by stoichiometry. Second, at the equimolar critical point (𝑟 = 1), the dispersity exhibits a profound singularity with non-commuting limits. Third, a Moving-Target Mechanism: while chain length grows monotonically with the feed ratio at fixed conversion, the optimal stoichiometry at a fixed reaction time migrates dynamically with 𝛼, allowing fast-asymmetric systems to achieve molecular weights nearly an order of magnitude higher than classical equimolar yields. Ultimately, this framework identifies a falsifiable end-group signature to reverse-engineer 𝛼 , transforming long-standing polycondensation anomalies into predictable, mathematically rigorously controllable levers for macromolecular design.",
  "abstract_shown": true,
  "affiliations": [
    "Hubei Key Laboratory for New Textile Materials and Applications",
    "Wuhan Textile University"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 1,
  "authors": [
    {
      "affs": [
        0,
        1
      ],
      "name": "Qingquan Tang",
      "orcid": "0000-0002-1519-1570"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/6xzt8w668hcz5.bib",
  "cited_by": 0,
  "doi": "10.26434/chemrxiv.15009468/v1",
  "fulltext_url": null,
  "id": "6xzt8w668hcz5",
  "issns": [],
  "landing_url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15009468/v1",
  "language": null,
  "licence": "CC-BY-NC-ND",
  "licence_label": "CC BY-NC-ND",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "1605|Advanced Polymer Synthesis and Characterization"
    ]
  ],
  "openalex": "W7214343858",
  "pdf_url": "https://chemrxiv.org/doi/pdf/10.26434/chemrxiv.15009468/v1",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-25",
  "publisher": "American Chemical Society (ACS)",
  "ris": "https://research.draconitic.com/paper/6xzt8w668hcz5.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:21Z",
      "native_id": "10.26434/chemrxiv.15009468",
      "source": "chemrxiv",
      "url": "https://chemrxiv.org/doi/full/10.26434/chemrxiv.15009468/v1"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "openalex:1605|Advanced Polymer Synthesis and Characterization",
      "subfield": "organic"
    }
  ],
  "title": "A Unified Theory for Generalized Step-Growth Polymerization: From Flory’s Equal‑Reactivity to Kinetic Symmetry‑Breaking",
  "title_text": "A Unified Theory for Generalized Step-Growth Polymerization: From Flory’s Equal‑Reactivity to Kinetic Symmetry‑Breaking",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:21Z",
  "url": "https://research.draconitic.com/paper/6xzt8w668hcz5",
  "venue": "ChemRxiv",
  "versions": []
}