{"paper":{"title":"Simulation Study of Sulfonate Cluster Swelling in Ionomers","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"Sulfonate clusters in low-concentration Nafion split at the start of hydration, then swell while keeping a fixed number of ions per cluster.","cross_cats":["cond-mat.soft"],"primary_cat":"cond-mat.mtrl-sci","authors_text":"Elshad Allahyarov, Hartmut L\\\"owen, Philip L. Taylor","submitted_at":"2009-09-03T01:04:13Z","abstract_excerpt":"We have performed simulations to study how increasing humidity affects the structure of Nafion-like ionomers under conditions of low sulfonate concentration and low humidity. At the onset of membrane hydration, the clusters split into smaller parts. These subsequently swell, but then maintain constant the number of sulfonates per cluster. We find that the distribution of water in low-sulfonate membranes depends strongly on the sulfonate concentration. For a relatively low sulfonate concentration, nearly all the side-chain terminal groups are within cluster formations, and the average water loa"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"At the onset of membrane hydration, the clusters split into smaller parts. These subsequently swell, but then maintain constant the number of sulfonates per cluster.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"The simulation force fields and low-concentration regime chosen are representative of real Nafion behavior at the onset of hydration.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"Hydration splits sulfonate clusters in low-concentration ionomers, after which clusters swell at constant sulfonate count while water distribution turns non-uniform at higher concentrations.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Sulfonate clusters in low-concentration Nafion split at the start of hydration, then swell while keeping a fixed number of ions per cluster.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"896bf50f327c56a3b48be6db8f437561448cadde84d38376f091e400982095fe"},"source":{"id":"0909.0559","kind":"arxiv","version":1},"verdict":{"id":"bb3134a2-8f9f-42ca-9982-f322b16d4c6b","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-14T20:24:05.700364Z","strongest_claim":"At the onset of membrane hydration, the clusters split into smaller parts. These subsequently swell, but then maintain constant the number of sulfonates per cluster.","one_line_summary":"Hydration splits sulfonate clusters in low-concentration ionomers, after which clusters swell at constant sulfonate count while water distribution turns non-uniform at higher concentrations.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"The simulation force fields and low-concentration regime chosen are representative of real Nafion behavior at the onset of hydration.","pith_extraction_headline":"Sulfonate clusters in low-concentration Nafion split at the start of hydration, then swell while keeping a fixed number of ions per cluster."},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":1,"snapshot_sha256":"5cef84a0451d977416040c1463aee4c111f3aac5cafe032d6adeafbcc93574ce"},"author_claims":{"count":1,"strong_count":1,"snapshot_sha256":"5e3b23b793a24ad44d50f012bed3c12f7c9e9c566d826ad85b79440943422c6c"},"builder_version":"pith-number-builder-2026-05-17-v1"}