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. 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 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 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 - benchmark: erosion_yield_atomic_oxygen value: 1.37e-24 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 - benchmark: density value: 1.1435 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 - benchmark: density value: 1.184 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 - benchmark: density value: 1.184 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.) - benchmark: density value: 1.17 value_high: 1.18 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 - benchmark: glass_transition_temperature value: 94 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 - benchmark: glass_transition_temperature value: 85 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 - benchmark: glass_transition_temperature value: 85 value_high: 100 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 - benchmark: glass_transition_temperature value: 95 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 - benchmark: melting_point value: 317 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 - benchmark: tga_onset_t5 value: 321 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 - benchmark: molecular_weight_average value: 150000 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 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 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. 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 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 license: CC-BY-4.0 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. story: 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 atoms: 3 atomic_weight: 12.011 role: Backbone and nitrile carbon of each repeat unit. - name: Hydrogen symbol: H atoms: 3 atomic_weight: 1.008 role: Backbone hydrogens of each repeat unit. - name: Nitrogen symbol: 'N' atoms: 1 atomic_weight: 14.007 role: Nitrile group that gives PAN its polar side groups and its carbon-fibre chemistry. risk_groups: - title: For people level: 0 verdict: Not classified hazardous 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. 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. 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 - label: Glass transition benchmark: glass_transition_temperature - label: Density benchmark: density 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. 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). - label: Serve as the precursor for most carbon fibre (Wikipedia line: 90 percent). 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.