{ "spore": "profile", "id": "pan", "spore_version": "0.2", "family": "engineering-polymers", "name": "Polyacrylonitrile", "abbreviation": "PAN", "role": "carbon fibre precursor and textile fibre polymer", "category": "polymers", "type": "acrylics", "summary": "Polyacrylonitrile is a vinyl polymer made from acrylonitrile. In the NASA MISSE 2 flight test on the outside of the ISS, a PAN sample had an atomic oxygen erosion yield of 1.41e-24 cm3/atom, close to the 1.37e-24 cm3/atom predicted by NASA's tool. Its glass transition is around 85 to 100 C, and it degrades near 300 C before it melts. Most of the world's carbon fibre is made from PAN.\n", "best_for": "Atomic-oxygen tolerance in low Earth orbit in the one flight data point collected here (NASA MISSE 2, about 3.95 years)", "weakest_at": "Only one flight result and one ground test of its erosion behaviour were found; no UV or thermal-cycling result for the neat polymer", "identity": { "formula": "(CH2CHCN)n, polyacrylonitrile; repeat unit (C3H3N)n from acrylonitrile", "cas": "25014-41-9", "designations": [], "source": "glentham-gk2612", "where": "Molecular formula and CAS number on the Glentham GK2612 datasheet; repeat unit from Wikipedia lead and infobox" }, "tags": { "environments": [ "low-earth-orbit" ], "stresses": [ "atomic-oxygen" ], "applications": [ "structures" ] }, "properties": [ { "benchmark": "erosion_yield_atomic_oxygen", "value": 1.41e-24, "bound": "exact", "unit": "cm3/atom", "scope": "material", "conditions": { "platform": "ISS, MISSE 2, PEC 2 tray 1 (outside the Quest airlock)", "fluence": "8.43e21 atoms/cm2", "duration": "about 3.95 years (2001-08-16 to 2005-07-30)" }, "method": "Measured flight erosion yield reported in the NASA predictive-tool report", "status": "flight", "source": "nasa-misse2-pan", "where": "Table I, MISSE 2 PEACE polymers erosion yield data, row Polyacrylonitrile", "source_detail": { "title": "Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit", "id": "NASA/TM-2008-215490", "url": "https://ntrs.nasa.gov/citations/20090011780", "year": 2008, "kind": "report", "license": "CC-BY-4.0" } }, { "benchmark": "erosion_yield_atomic_oxygen", "value": 1.37e-24, "bound": "exact", "unit": "cm3/atom", "scope": "material", "conditions": { "basis": "NASA predictive tool, same report; compared with the MISSE 2 flight value" }, "method": "Predicted by the NASA predictive tool (a calculated value, not a test)", "status": "calculated", "source": "nasa-misse2-pan", "where": "Table of measured atomic oxygen erosion yields, Predicted column, row Polyacrylonitrile", "source_detail": { "title": "Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit", "id": "NASA/TM-2008-215490", "url": "https://ntrs.nasa.gov/citations/20090011780", "year": 2008, "kind": "report", "license": "CC-BY-4.0" } }, { "benchmark": "density", "value": 1.1435, "bound": "exact", "unit": "g/cm3", "scope": "material", "conditions": { "basis": "reference density used by the NASA erosion tool; reference 12 in that report" }, "method": "Value printed in the NASA predictive-tool report density table", "status": "ground", "source": "nasa-misse2-pan", "where": "Table of polymer densities and ash mass fractions, row Polyacrylonitrile", "source_detail": { "title": "Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit", "id": "NASA/TM-2008-215490", "url": "https://ntrs.nasa.gov/citations/20090011780", "year": 2008, "kind": "report", "license": "CC-BY-4.0" } }, { "benchmark": "density", "value": 1.184, "bound": "exact", "unit": "g/cm3", "scope": "material", "conditions": { "basis": "Wikipedia infobox, no temperature stated" }, "method": "Value printed in the infobox of the Wikipedia article", "status": "ground", "source": "wikipedia-pan", "where": "Infobox, Properties", "source_detail": { "title": "Polyacrylonitrile (Wikipedia)", "id": "Wikipedia, Polyacrylonitrile", "url": "https://en.wikipedia.org/wiki/Polyacrylonitrile", "year": 2026, "kind": "web", "license": "CC-BY-SA-4.0" } }, { "benchmark": "density", "value": 1.184, "bound": "exact", "unit": "g/mL", "scope": "material", "conditions": { "temperature": "25 C", "grade": "average Mw 150,000 (typical)" }, "method": "Printed on the supplier's property listing (Sigma-Aldrich product 181315)", "status": "ground", "source": "sigma-pan-181315", "where": "Physical properties, density (lit.)", "source_detail": { "title": "Sigma-Aldrich 181315 polyacrylonitrile, average Mw 150,000 (reseller copy of listing)", "id": "Sigma-Aldrich product 181315", "url": "https://www.labor.com.tr/en/product/sigma-aldrich-181315-polyacrylonitrile-average-mw-150-000-typical-100-gr", "year": 2026, "kind": "datasheet" } }, { "benchmark": "density", "value": 1.17, "value_high": 1.18, "bound": "exact", "unit": "g/cm3", "scope": "material", "conditions": { "basis": "Material overview, no temperature stated" }, "method": "Range printed on the Goodfellow material information page", "status": "ground", "source": "goodfellow-pan", "where": "Material Overview", "source_detail": { "title": "Polyacrylonitrile (PAN) powder material information", "id": "Goodfellow material information", "url": "https://www.goodfellow.com/usa/resources/polyacrylonitrile-pan-powder-material-information/", "year": 2026, "kind": "datasheet" } }, { "benchmark": "glass_transition_temperature", "value": 94, "bound": "exact", "unit": "°C", "scope": "material", "conditions": { "method_detail": "DSC", "grade": "Sigma-Aldrich PAN, Mw 150,000, used as received" }, "method": "Differential scanning calorimetry value printed in a 2021 Scientific Reports paper (Table 3)", "status": "ground", "source": "sci-rep-pan-2021", "where": "Table 3, TgDSC, row PAN; text states The Tg for PAN is 94 C", "source_detail": { "title": "Effect of polyaniline content and protonating dopants on electroconductive composites", "id": "Scientific Reports, 2021 (PMC8021568)", "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC8021568/", "year": 2021, "kind": "paper", "license": "open access" } }, { "benchmark": "glass_transition_temperature", "value": 85, "bound": "exact", "unit": "°C", "scope": "material", "conditions": { "grade": "average Mw 150,000 (typical)" }, "method": "Typical value printed on the Sigma-Aldrich property listing", "status": "ground", "source": "sigma-pan-181315", "where": "Physical properties, Tg", "source_detail": { "title": "Sigma-Aldrich 181315 polyacrylonitrile, average Mw 150,000 (reseller copy of listing)", "id": "Sigma-Aldrich product 181315", "url": "https://www.labor.com.tr/en/product/sigma-aldrich-181315-polyacrylonitrile-average-mw-150-000-typical-100-gr", "year": 2026, "kind": "datasheet" } }, { "benchmark": "glass_transition_temperature", "value": 85, "value_high": 100, "bound": "exact", "unit": "°C", "scope": "material", "conditions": { "basis": "range for PAN resins, no grade stated" }, "method": "Range printed in the Material Overview of the Goodfellow page", "status": "ground", "source": "goodfellow-pan", "where": "Material Overview", "source_detail": { "title": "Polyacrylonitrile (PAN) powder material information", "id": "Goodfellow material information", "url": "https://www.goodfellow.com/usa/resources/polyacrylonitrile-pan-powder-material-information/", "year": 2026, "kind": "datasheet" } }, { "benchmark": "glass_transition_temperature", "value": 95, "bound": "exact", "unit": "°C", "scope": "material", "conditions": { "basis": "stated as around 95 C; no grade or method given" }, "method": "Value printed in the Physical properties section of the Wikipedia article", "status": "ground", "source": "wikipedia-pan", "where": "Physical properties", "source_detail": { "title": "Polyacrylonitrile (Wikipedia)", "id": "Wikipedia, Polyacrylonitrile", "url": "https://en.wikipedia.org/wiki/Polyacrylonitrile", "year": 2026, "kind": "web", "license": "CC-BY-SA-4.0" } }, { "benchmark": "melting_point", "value": 317, "bound": "exact", "unit": "°C", "scope": "material", "conditions": { "grade": "average Mw 150,000 (typical)" }, "method": "Melting point printed on the Sigma-Aldrich property listing; the Wikipedia article says PAN degrades before melting", "status": "ground", "source": "sigma-pan-181315", "where": "Physical properties, Tm", "source_detail": { "title": "Sigma-Aldrich 181315 polyacrylonitrile, average Mw 150,000 (reseller copy of listing)", "id": "Sigma-Aldrich product 181315", "url": "https://www.labor.com.tr/en/product/sigma-aldrich-181315-polyacrylonitrile-average-mw-150-000-typical-100-gr", "year": 2026, "kind": "datasheet" } }, { "benchmark": "tga_onset_t5", "value": 321, "bound": "exact", "unit": "°C", "scope": "material", "conditions": { "method_detail": "TGA, 5 percent weight loss (T5)", "grade": "Sigma-Aldrich PAN, Mw 150,000" }, "method": "Thermogravimetric value printed in Table 3 of a 2021 Scientific Reports paper", "status": "ground", "source": "sci-rep-pan-2021", "where": "Table 3, T5, row PAN", "source_detail": { "title": "Effect of polyaniline content and protonating dopants on electroconductive composites", "id": "Scientific Reports, 2021 (PMC8021568)", "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC8021568/", "year": 2021, "kind": "paper", "license": "open access" } }, { "benchmark": "molecular_weight_average", "value": 150000, "bound": "exact", "unit": "g/mol", "scope": "material", "conditions": { "basis": "average molecular weight of the polymer as listed by the supplier, approximate" }, "method": "Printed on the Glentham GK2612 datasheet (approx. 150,000) and the Sigma-Aldrich listing (average Mw 150,000 typical)", "status": "ground", "source": "glentham-gk2612", "where": "Structure, Molecular Weight", "source_detail": { "title": "Glentham GK2612 Polyacrylonitrile, m.w. approx. 150,000 product datasheet", "id": "Glentham GK2612 (v1.0)", "url": "https://www.glentham.com/en/products/product/GK2612/datasheet", "year": 2026, "kind": "datasheet" } } ], "corrosion": [], "risks": { "hazards": [ { "text": "Glentham datasheet for GK2612 polyacrylonitrile: not classified as hazardous under CLP and not classified as dangerous for transport.", "ghs": [], "source": "glentham-gk2612", "where": "Hazards and Transport" }, { "text": "ChemicalBook SDS for polyacrylonitrile (CB9199592): hazard classification and hazard statements both read no data available; first aid is given for inhalation, skin, eye and ingestion.", "ghs": [], "source": "chemicalbook-pan-sds", "where": "Sections 2 and 4" } ], "failure_risks": [ { "mode": "Degradation before melting under heat", "trigger": "Heating above about 300 C", "consequence": "Onset of thermal degradation near 300 C; the sample in the Scientific Reports paper lost 0.8 percent of its weight at 300 C and was about 321 C at 5 percent loss.", "severity": "low", "source": "sci-rep-pan-2021", "where": "Table 3, weight loss at 300 C and T5" } ], "side_effects": [], "handling": [ { "text": "Glentham gives a recommended storage temperature of +20 C for the powder and a water content of 1.0 percent or less.", "source": "glentham-gk2612", "where": "Storage and Product Specification" } ], "mitigations": [] }, "uses": [ { "application": "structures", "device": "Precursor for carbon fibre", "example": "Wikipedia says PAN is used as the precursor for 90 percent of carbon fibre production.", "source": "wikipedia-pan", "where": "Applications, Carbon fiber" } ], "supply": [], "media": [], "documents": [ { "title": "NASA TM-2008-215490, atomic oxygen erosion yield predictive tool (MISSE 2 PEACE data)", "type": "report", "url": "https://ntrs.nasa.gov/citations/20090011780", "year": 2008 }, { "title": "Glentham GK2612 Polyacrylonitrile product datasheet", "type": "datasheet", "url": "https://www.glentham.com/en/products/product/GK2612/datasheet", "year": 2026 }, { "title": "ChemicalBook polyacrylonitrile SDS", "type": "sds", "url": "https://www.chemicalbook.com/msds/polyacrylonitrile.htm", "year": 2026 }, { "title": "Scientific Reports 2021, electroconductive PAN/PANI composites (open access)", "type": "paper", "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC8021568/", "year": 2021 } ], "gaps": [ "Only one sourced use was found. Textile fibre use is named in general but no fetched page with a printed value was read for it.", "Supply: no fetched source for who produces PAN or its share by country was found. The acrylonitrile feedstock and critical-mineral status were not checked.", "UV, thermal-cycling and humidity effects on neat PAN were not found in a fetched source.", "Tensile strength and modulus values were not read from a fetched page. A search snippet gave ranges from patents, which are not used here.", "PubChem record could not be opened (blocked by a verification screen), so its GHS summary is not used.", "A second supplier SDS (Acros/Fisher) was found only as a search snippet and not fetched, so its irritation and cyanide statements are not used.", "Sigma-Aldrich product page and Merck page timed out, so the Sigma values come from a reseller copy (labor.com.tr).", "Atomic oxygen erosion yield for PAN is one flight data point (MISSE 2); no separate ground AO test was read." ], "story": { "why": "Polyacrylonitrile is a vinyl polymer made from acrylonitrile. Its glass transition sits near 85 to 100 C and it degrades near 300 C before melting. The MISSE 2 flight test gave an atomic oxygen erosion yield of 1.41e-24 cm3/atom.", "uses": [ { "where": "Carbon fibre", "line": "Wikipedia says PAN is used as the precursor for 90 percent of carbon fibre production." } ], "can_do": [ { "label": "Strength", "line": "Survive the atomic oxygen of low Earth orbit with a small erosion yield in the MISSE 2 flight test (1.41e-24 cm3/atom).", "scope": "material" }, { "label": "Serve as the precursor for most carbon fibre (Wikipedia", "line": "90 percent).", "scope": "material" } ], "compare": "PAN is a high-glass-transition acrylic. Its atomic oxygen erosion yield of 1.41e-24 cm3/atom in MISSE 2 is in the same range as polystyrene and the other low-yield polymers in the NASA table. Its thermal behaviour is set by degradation near 300 C rather than melting. The table compares PAN with the other polymers in the collection.", "compare_rows": [ { "label": "Atomic oxygen erosion yield (flight)", "benchmark": "erosion_yield_atomic_oxygen", "scope": "material" }, { "label": "Glass transition", "benchmark": "glass_transition_temperature", "scope": "material" }, { "label": "Density", "benchmark": "density", "scope": "material" } ], "handling": [ "The powder is not classified as hazardous in the supplier datasheet. Keep it dry and store near 20 C.", "Heating above about 300 C causes degradation, so keep processing temperatures below that." ], "good_for": [ "Atomic oxygen tolerance in low Earth orbit. The MISSE 2 flight gave a yield of 1.41e-24 cm3/atom, close to the 1.37e-24 cm3/atom predicted.", "Carbon fibre precursor. Wikipedia says 90 percent of carbon fibre is made from PAN." ], "watch_out": [ "Degradation near 300 C, below its melting point.", "Only one flight result and one predictive tool value were found for erosion; there is no UV or thermal-cycling result for neat PAN." ], "verdict": "PAN is a useful reference for low-erosion polymers in low Earth orbit, with a single flight point and a well-established carbon-fibre route. Its UV and thermal-cycling behaviour are not yet supported by data in this file.", "recipe": { "line": "Polyacrylonitrile is a vinyl polymer. Each repeat unit is one acrylonitrile monomer, CH2CHCN, polymerised by free-radical polymerisation.", "parts": [ { "name": "Carbon", "symbol": "C", "role": "Backbone and nitrile carbon of each repeat unit.", "atoms": 3, "atomic_weight": 12.011 }, { "name": "Hydrogen", "symbol": "H", "role": "Backbone hydrogens of each repeat unit.", "atoms": 3, "atomic_weight": 1.008 }, { "name": "Nitrogen", "symbol": "N", "role": "Nitrile group that gives PAN its polar side groups and its carbon-fibre chemistry.", "atoms": 1, "atomic_weight": 14.007 } ] }, "risk_groups": [ { "title": "For people", "lead": "The supplier datasheet says not classified; a second SDS gives no hazard data.", "points": [ { "label": "The polymer", "line": "The Glentham datasheet says not classified as hazardous under CLP. ChemicalBook prints no data available for hazard classification." } ], "level": 0, "verdict": "Not classified hazardous" } ] }, "updated": "2026-10-20", "review": { "status": "draft", "method": "assistant", "checked_values": 13, "unreachable": 4, "caveats": 2, "note": "Read by an AI assistant on 2026-10-20 from pages fetched in this run. PubChem, Sigma product page and Merck page could not be opened." }, "sources": { "nasa-misse2-pan": { "title": "Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit", "id": "NASA/TM-2008-215490", "url": "https://ntrs.nasa.gov/citations/20090011780", "year": 2008, "kind": "report", "license": "CC-BY-4.0" }, "wikipedia-pan": { "title": "Polyacrylonitrile (Wikipedia)", "id": "Wikipedia, Polyacrylonitrile", "url": "https://en.wikipedia.org/wiki/Polyacrylonitrile", "year": 2026, "kind": "web", "license": "CC-BY-SA-4.0" }, "goodfellow-pan": { "title": "Polyacrylonitrile (PAN) powder material information", "id": "Goodfellow material information", "url": "https://www.goodfellow.com/usa/resources/polyacrylonitrile-pan-powder-material-information/", "year": 2026, "kind": "datasheet" }, "sci-rep-pan-2021": { "title": "Effect of polyaniline content and protonating dopants on electroconductive composites", "id": "Scientific Reports, 2021 (PMC8021568)", "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC8021568/", "year": 2021, "kind": "paper", "license": "open access" }, "sigma-pan-181315": { "title": "Sigma-Aldrich 181315 polyacrylonitrile, average Mw 150,000 (reseller copy of listing)", "id": "Sigma-Aldrich product 181315", "url": "https://www.labor.com.tr/en/product/sigma-aldrich-181315-polyacrylonitrile-average-mw-150-000-typical-100-gr", "year": 2026, "kind": "datasheet" }, "glentham-gk2612": { "title": "Glentham GK2612 Polyacrylonitrile, m.w. approx. 150,000 product datasheet", "id": "Glentham GK2612 (v1.0)", "url": "https://www.glentham.com/en/products/product/GK2612/datasheet", "year": 2026, "kind": "datasheet" }, "chemicalbook-pan-sds": { "title": "ChemicalBook polyacrylonitrile SDS (CB9199592)", "id": "CB9199592", "url": "https://www.chemicalbook.com/msds/polyacrylonitrile.htm", "year": 2026, "kind": "datasheet" } }, "license": "CC-BY-4.0", "url": "https://spacemushroom.com/profiles/pan/" }