3D Printing Info

Filament comparison

rPLA vs PPA

Compare printing settings, strength, heat resistance, dated prices and sources.

Recycled PLA (rPLA) guidePPA (polyphthalamide) guide

2 selected · all documented properties

Open these two in the interactive comparisonMore rPLA comparisonsMore PPA comparisons
rPLA vs PPA — documented properties and sources
PropertyRecycled PLA (rPLA)PLAPPA (polyphthalamide)PA
Market snapshot
Listing priceUSD/kg; dated snapshots$20.79/kg median; $16.05–$40.64/kg across 8 dated product listings$45.49/kg median; $45.49–$45.49/kg across 1 dated product listings
Identity & Market
Base polymer / chemistryPLA regranulated from post-industrial PLA manufacturing waste; post-consumer feedstock is rare[1][2][3]Polyphthalamide — a semi-aromatic polyamide in which aromatic diacid units replace part of the aliphatic backbone; Raise3D and Bambu Lab both label it high-temperature nylon[4][5]
Densityg/cm³1.24 (ISO 1183)[1]1.21 (ISO 1183, Siraya Tech Fibreheart PPA)[6]
Typical priceUSD/kg1 kg spools run 20–22[7][8][9]One 1 kg listing on the market, at 45[10]
Price range across brandsUSD/kg16–41 across brands; Fiberlogy refill 16, Filamentive 750 g 41[11][12]45 for the only unfilled PPA filament found — Siraya Tech Fibreheart PPA at 1 kg; every other PPA in retail is carbon- or glass-filled[10]
Market availability1–5Available from several mainstream brands[2][3][9]Special order, 1–2 makers worldwide — Siraya Tech is the only brand found selling unfilled PPA filament[10]
Spool sizes & diameters1.75 and 2.85 mm; 0.75, 0.85 and 1 kg spools plus spool-less refills[13][11][2]1.75 mm, 1 kg[10]
Typical applicationsGeneral-purpose printing where the feedstock's recycled content matters more than an exact colour match[2][3]Gears, bearings and tooling that must hold load above the reach of PA6 or PA12, and parts exposed to fuels and industrial chemicals[6]
Diameter tolerance± mm±0.03 guaranteed by Prusa Research today; the 2021 datasheet specified ±0.05, against ±0.02 for virgin Prusament PLA[2][1][14]Not documented
Printing Parameters
Nozzle temperature°C210 ± 10 (Prusament); 200 ± 15 (Filamentive)[1][3]280–300 (Siraya Tech)[6]
Bed temperature°C40–60 (Prusament); up to 60 (Filamentive)[1][3]70–80 (Siraya Tech)[6]
Enclosure / chamber requirement1–5Open frame is fine[1][15]Enclosure recommended — Siraya Tech advises an enclosure to hold temperature and limit warping on larger prints[6]
Part cooling fan100 %[1]20–60 % (Siraya Tech)[6]
Bed surface & adhesion aidNot documentedPEI sheet with a glue stick, or a PVP glue coating[6]
Warping tendency1–5None — brim not generally needed[1]Not documented
Bed-adhesion difficulty1–5Sticks to anything[16]Not documented
Overall printing difficulty1–5Beginner — prints on any machine out of the box[1][15]Advanced — enclosure, hardware upgrades, tuning; needs a 300 °C-class hot end and a dry spool[6]
Hardware Wear & Reliability
Nozzle hardness required1–4Brass fine indefinitely[15]Brass fine indefinitely — Siraya Tech states a hardened steel nozzle is not needed for the unfilled grade[6]
Abrasiveness1–5Non-abrasive[17][15]Non-abrasive when unfilled[6]
Nozzle clog risk1–5Very low[15]Moderate — needs dry filament and a clean nozzle; Siraya Tech tells users to dry only when moisture symptoms appear, rather than before every print[6]
Heat-creep / jam sensitivity1–5Moderate — good heatbreak cooling needed; PLA softens below 60 °C[18]Not documented
Hotend requirementNo special hot-end required[16]High-quality metal nozzle, 0.4–1.0 mm; hardened steel not required (Siraya Tech)[6]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Moderate — 0.3 % after both 24 h and 7 days at 28 °C / 37 % RH (Prusa Polymers method), against 0.19 % in 7 days for virgin Prusament PLA[1][14]High (0.8–2 %) — Siraya Tech publishes 2.59 % by ISO 62 immersion for the unfilled grade; on the equilibrium basis Bambu Lab uses, its 15 % carbon-filled PPA reaches 1.30 % against 2.35 % for the same maker's PA6-CF[6][5][19]
Equilibrium moisture content at ~50 % RH%0.3 after 24 h and 7 days at 28 °C / 37 % RH (Prusa Polymers method)[1]2.59 by ISO 62 water immersion (Siraya Tech, unfilled) — an immersion figure, not the 25 °C / 55 % RH equilibrium basis the filled grades are quoted on, so the two are not directly comparable[6]
Drying temperature & timeNot documented80–100 °C for 4–6 h (Siraya Tech)[6]
Symptoms when wetBubbling and popping at the nozzle, stringing, rough surface and weak layers[20]Oozing, bubbles and a rough surface finish (Siraya Tech)[6]
Effect of moisture on strengthPolymaker rates PLA low-sensitivity — the loss shows as poor layer adhesion and brittle layers rather than a published strength figure[20]Siraya Tech publishes dry against saturated for the same grade: tensile 70 → 60 MPa, flexural 114 → 87 MPa, HDT at 1.8 MPa 73.5 → 48.5 °C, while Charpy rises 10 → 14.5 kJ/m²[6][10]
Storage requirementSealed with desiccant below 20 % RH; shelf life at ambient is long[21][16]Dry box below 15 % RH (Siraya Tech)[6]
Mechanical Properties
Tensile strength (XY)MPa49 printed horizontal and 55 printed vertical XZ (ISO 527-1, yield); virgin Prusament PLA gives 51 and 59 by the same method[1][14]72 at break (printed, ASTM D638, Siraya Tech); the product page quotes 70 dry and 60 saturated[6][10]
Young's modulusMPa2100 printed horizontal, 2300 printed vertical XZ (ISO 527-1); virgin Prusament PLA 2300 and 2400[1][14]3600 (printed, ASTM D638, Siraya Tech)[6]
Elongation at break%3.1 at yield printed horizontal (ISO 527-1); virgin Prusament PLA 2.9[1][14]10.5 at break (printed, ASTM D638, Siraya Tech)[6]
Flexural strengthMPa82 printed horizontal, 87 printed vertical XZ (ISO 178); virgin Prusament PLA 83 and 99[1][14]115 (printed, ISO 178, Siraya Tech); 114 dry against 87 saturated on the product page[6][10]
Flexural modulusMPa3100 printed horizontal (ISO 178) — the same as virgin Prusament PLA[1][14]3350 (printed, ISO 178, Siraya Tech)[6]
Charpy impact, notchedkJ/m²Not documented10.1 Charpy (printed, ISO 179, Siraya Tech); the data sheet does not state whether the specimen was notched[6]
Other impact dataCharpy unnotched 14.0 printed horizontal (ISO 179-1); virgin Prusament PLA 13[1][14]Not documented
Layer adhesion / Z tensileMPa21 ± 2 (Prusa Polymers interlayer adhesion test); virgin Prusament PLA 17 ± 3 by the same test[1][14]Not documented
Brittleness1–5Brittle — snaps with little warning[18][17]Moderate — 10.5 % elongation at break puts it between PA6 and the fibre-filled grades[6]
Hardness (scale-specific)Shore A / Shore D / Rockwell80 Shore D (Prusa Polymers in-house method); virgin Prusament PLA 81[1][14]Not documented
Creep resistance / sustained load1–5Poor — no recycled-PLA creep data published; virgin PLA sagged from 12 to 18.7–20.3 mm over 5 days at 1.25 kg[22][23]Good — Raise3D cites high creep resistance as a reason to choose the PPA matrix over other nylons[4]
Fatigue / repeated-flex resistance1–5Poor — no grade-specific S-N curve; plain printed PLA ran 38 000–49 000 cycles at 30 % of tensile strength (R = 0.2)[24][18]Not documented
Elasticity / flexibility1–5Rigid[17]Rigid — 3.6 GPa tensile modulus[6]
Wear resistance & frictionNot documentedSiraya Tech describes the unfilled grade as low-friction and self-lubricating, aimed at gears and bearings[6][10]
Thermal Properties
HDT at 0.45 MPa°C55 (ISO 75, 0.45 MPa) — the same as virgin Prusament PLA[1][14]81 dry and 61 saturated (printed, ISO 75 Method B at 0.45 MPa, Siraya Tech)[6]
HDT at 1.8 MPa°C53 (ISO 75, 1.8 MPa); virgin Prusament PLA 55[1][14]73.5 dry and 48.5 saturated (printed, ISO 75 Method A at 1.8 MPa, Siraya Tech) — unfilled PPA deflects near its Tg; the 190–227 °C figures quoted for PPA are carbon-filled grades[6][5]
Glass transition (Tg)°CNot documented80 (ASTM D3418, Siraya Tech)[6]
Melting point / Vicat°CNot documented231 melting point (ASTM D3418) and 230 Vicat (ISO 306), Siraya Tech[6]
Continuous service temperature°C55 (Filamentive states heat resistance up to 55 °C)[3]Not documented
Annealing responseNot documentedSiraya Tech's product page offers annealing for strength while its own data sheet says annealing is not recommended because the print can warp; on its 15 % carbon-filled PPA, annealing lifts HDT at 1.8 MPa from 82.5 to 119 °C[6][10][25]
Thermal expansion (CTE)µm/m·K96–99 for plain printed PLA (fibre Bragg grating, 25–50 °C); no grade-specific measurement published[26]Not documented
Flammability / UL 94Flammable; no UL 94 rating published by the major brands[21][27]Not documented
Environment & Chemical
UV resistance1–5Degrades within weeks outdoors[18][28]Not documented
Chemical resistanceGood against weak acids, oils and grease; poor against strong acids and alkalis; dissolved by chloroform, THF and hot benzene[27][18]Withstands fuels, oils and industrial chemicals; Bambu Lab rates semi-aromatic nylon better than general nylon against weak acids, weak alkalis and most organic solvents[6][5]
Water / humidity resistance in service1–5Good — insoluble in water[21]Absorbs water, properties shift — a saturated specimen loses about 15 % of its tensile strength and 25 °C of heat-deflection temperature[6][10]
Food contactFilamentive certifies its rPLA to EN 71-3 and lists it food safe; printed layer grooves still harbour bacteria[3][18]Not documented
Biodegradability / compostabilityIndustrially compostable only — needs sustained 55 °C; not home compostable[3]Not documented
RecyclabilityThe feedstock itself; Filamentive uses 50 % post-industrial content and runs a PLA take-back scheme[3][12]Not documented
Health & Safety
Fume toxicity1–5Low hazard — minimal VOC and particle emission[29]Not documented
Hazardous species emittedPrusament rPLA Corn Pigment uses organic waste pigments such as red algae, which give a noticeable scent while printing[2]Not documented
Ventilation / filtration requirement1–5None needed in a normal room[29]Not documented
Post-Processing
Sanding & machiningWet sanding — dry sanding heats the surface by friction and smears it[28][18]Not documented
Gluing & solvent weldingSuperglue for most joints; acetone works on some grades depending on additives and colour[2]Not documented
Vapour / chemical smoothingNo practical vapour smoothing — only chloroform, hot benzene or THF, which are laboratory-only[18]Not documented
Support material pairingNot documentedCompatible with quick-release support materials (Siraya Tech)[6]
Solvents & Solubility
Soluble inChloroform: 10 % w/v in 2–4 h at 23 °C, every grade and morphology; THF and DMF only at 65 °C. Laboratory reagents.[30]Dissolved at 23 °C by formic acid, phenol, m-cresol, 96 % sulphuric acid or hexafluoroisopropanol — all laboratory reagents.[31]
Softened or crazed byAcetone, ethyl acetate and toluene plasticise it but dissolve <1 % even at 65 °C; submersion in acetone crazes and destroys parts.[30][32]Mineral acids, oxidants, halogens and zinc chloride solutions attack the amide bond; ordinary solvents do not.[31]
Solvent welding & smoothing agentChloroform vapour smooths and welds PLA at the cost of tensile strength; acetone does not smooth it at all.[33][32]None — nylon's only solvents are formic acid, phenol and HFIP, all of which degrade the part they wet.[31]

Material entries describe families or representative grades, not an interchangeable specification for every spool. Test methods, orientations and conditions may differ. Unknown values are marked “Not documented”. Prices and source dates remain historical snapshots; check the linked guide for product details. Differences highlight text, not a universal winner.

Sources for this comparison

  1. Prusament PLA Recycled Technical Datasheet v1.0 Prusa Polymers · 2021-12 · tds
  2. Prusament rPLA Corn Pigment 1kg — product page Prusa Research · 2026-08 · vendor
  3. Filamentive PLA (recycled) — product page Filamentive · 2026-08 · vendor
  4. Raise3D Industrial PPA CF Technical Data Sheet V2.0 Raise3D · 2022-04 · tds
  5. Bambu Filament Technical Data Sheet V1.0 — PPA-CF Bambu Lab · 2026-08 · tds
  6. Siraya Tech Fibreheart PPA Technical Data Sheet Siraya Tech · 2026-08 · tds
  7. 3D-Fuel ReFuel Recycled PLA 1kg 3D-Fuel · 2026-08 · vendor
  8. Proto-pasta Black Recycled PLA 1kg Proto-pasta · 2026-08 · vendor
  9. Formfutura ReForm rPLA (White) 1kg Filament2Print · 2026-08 · vendor
  10. Siraya Tech Fibreheart PPA Filament — product page Siraya Tech · 2026-08 · vendor
  11. Fiberlogy rPLA Refill Anthracite 850 g 3DJake International · 2026-08 · vendor
  12. Filamentive PLA (rPLA) 750 g CREATE Education · 2026-08 · vendor
  13. Kimya PLA-R 750 g Crea3D · 2026-08 · vendor
  14. Prusament PLA Technical Datasheet v1.1 Prusa Polymers · 2022-02 · tds
  15. Filament Material Guide Prusa Knowledge Base · 2026-08 · doc
  16. PLA — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  17. Prusament PLA — material page Prusa Polymers · 2026-08 · doc
  18. PLA — material guide Prusa Knowledge Base · 2026-08 · doc
  19. Bambu Filament Technical Data Sheet V3.0 — PA6-CF Bambu Lab · 2026-08 · tds
  20. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  21. Bambu Filament Technical Data Sheet V3.0 — PLA Basic Bambu Lab · 2026-08 · tds
  22. BambuLab PLA Basic vs PLA Tough vs PLA-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  23. PolyTerra PLA vs PLA+ — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  24. Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
  25. Siraya Tech Fibreheart PPA-CF Technical Data Sheet Siraya Tech · 2026-08 · tds
  26. Characterization of Thermal Expansion Coefficient of 3D Printing Polymeric Materials Using Fiber Bragg Grating Sensors Materials 17(18):4668 · 2024-09 · paper
  27. PolyLite PLA Technical Data Sheet V5.4 Polymaker · 2024-11 · tds
  28. Prusament PLA Technical Data Sheet v1.0 Prusa Polymers · 2018-09 · tds
  29. Emissions of Ultrafine Particles and Volatile Organic Compounds from Commercially Available Desktop Three-Dimensional Printers with Multiple Filaments (Azimi et al.) Environmental Science & Technology 50(3) 1260-1268 · 2016-01 · paper
  30. Solubility Study of Ingeo Biopolymer Grades in Common Organic Solvents (NWPD003) NatureWorks · 2019-10 · tds
  31. Ultramid Nylon Chemical Resistance guide (unmodified PA6 B27E and PA66 A27E) BASF · 2026-08 · tds
  32. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc
  33. Effect of vapour smoothing in trichloromethane on 3D printed PLA — surface, mechanical and chemical structure Pitale, Keche & Chopra, Engineering Research Express 6(4) 045579 · 2024-12 · paper