3D Printing Info

Filament comparison

PETG-GF vs PP-GF

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

Glass-fibre polyester (PETG-GF / PET-GF) guideGlass-fibre PP (PP-GF) guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PETG-GF comparisonsMore PP-GF comparisons
PETG-GF vs PP-GF — documented properties and sources
PropertyGlass-fibre polyester (PETG-GF / PET-GF)PETGGlass-fibre PP (PP-GF)POLYOLEFIN
Market snapshot
Listing priceUSD/kg; dated snapshots$27.38/kg median; $18.99–$29.99/kg across 3 dated product listings$49.09/kg median; $46.27–$86.01/kg across 3 dated product listings
Identity & Market
Base polymer / chemistryGlass-fibre reinforced polyester. Polymaker's Fiberon PET-GF15 uses a PET rather than a PETG matrix and carries 15 wt% glass fibre[1]Polypropylene reinforced with chopped glass fibre[2][3]
Densityg/cm³1.43 (Fiberon PET-GF15, ISO 1183)[1]1.12 (Prusament PP Glass Fiber, ISO 1183) — the glass lifts it above water[2]
Typical priceUSD/kg1 kg spools cluster near 25[4][5]1 kg-equivalent spools cluster near 49[6][7][8]
Price range across brandsUSD/kg19–30 across brands; ELEGOO 19, Polymaker Fiberon 30[4][5]46-86 across brands; BCN3D PP GF30 46 at 700 g, BASF Ultrafuse PP GF30 49 at 2.2 kg, Prusament PP Glass Fiber 86 at 850 g[6][7][8]
Market availability1–5Niche, a handful of specialist brands[4][5]Available from several mainstream brands[6][7][8]
Spool sizes & diameters1.75 mm; 0.5 and 1 kg spools[5]1.75 and 2.85 mm; 700 g, 850 g and 2.2 kg spools[6][7][8]
Typical applicationsStiff, dimensionally stable fixtures; the Fiberon grade is designed to be annealed for heat resistance[1]Stiff, chemically resistant parts where PP-CF's cost or conductivity is unwanted[3]
Diameter tolerance± mmNot documented±0.04 (Prusament)[2]
Printing Parameters
Nozzle temperature°CNot documented245 ± 10 (Prusament) — 25 °C below the carbon-fibre grade[2][9]
Bed temperature°CNot documented95 ± 10 (Prusament)[2]
Enclosure / chamber requirement1–5Not documentedEnclosure recommended — Simplify3D lists an enclosure as a hardware requirement and Polymaker advises one below 70 °C ambient to stop warping and cracking[10][11]
Part cooling fanNot documentedOff — Prusa runs 0 % except 100 % on bridges[2]
Bed surface & adhesion aidTextured PEI, satin or powder-coated sheets; on smooth PEI a glue stick acts as a release agent[12][13]Not documented
Maximum volumetric flow (mm³/s; see test conditions)mm³/sNot documented4 at Prusa's 50 mm/s cap on a 0.4 mm nozzle at 0.2 mm layer[2][14]
Warping tendency1–5Not documentedHigh — enclosure needed for reliable large parts; Prusa recommends a brim[2]
Bed-adhesion difficulty1–5Needs the right surface or a thin adhesive — the problem is releasing the part, not sticking it[12][13]Very difficult — special plates or slurry required[2]
Stringing / oozing tendency1–5Moderate — retraction tuning needed; Polymaker names stringing as PETG's common quirk[13]Not documented
Overall printing difficulty1–5Not documentedAdvanced — enclosure, hardware upgrades, tuning; hardened nozzle mandatory[2]
Extruder requirementNot documentedPrusa states a hardened nozzle is necessary and recommends a brim[2]
Hardware Wear & Reliability
Nozzle hardness required1–4Hardened steel required[1]Hardened steel required[2]
Abrasiveness1–5Highly abrasive — standard GF composite[1]Highly abrasive — standard GF composite[2]
Nozzle clog risk1–5Moderate — needs dry filament and a clean nozzle; Prusa lists higher risk of nozzle clogging for glass-filled composites[15]Moderate — needs dry filament and a clean nozzle; Prusa lists higher risk of nozzle clogging for glass-filled composites[15]
Heat-creep / jam sensitivity1–5Slightly sensitive[16]Not documented
Hotend requirementNo special hot-end required[16]Not documented
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Moderate (0.3–0.8 %) — the PETG matrix reaches 0.40 % saturated at 25 °C / 55 % RH; no glass-filled grade publishes its own figure[12]Low (0.1–0.3 %) — 0.11 % at both 24 h and 7 days, higher than the carbon-fibre grade's 0.04 % but still very low[2][9]
Equilibrium moisture content at ~50 % RH%Not documented0.11 after 24 h and 0.11 after 7 days at 24 °C / 22 % RH (Prusa Polymers)[2]
Symptoms when wetBubbling and popping at the nozzle, stringing and a rough surface[17]Not documented
Effect of moisture on strengthPolymaker groups PETG with nylon, PVA and TPU as highly hygroscopic; no dry-versus-conditioned strength figures are published for this grade and the loss shows as bubbling and poor layer adhesion[17]Not applicable in practice at 0.11 % equilibrium uptake[2]
Storage requirementSealed with desiccant; Polymaker groups PETG with the highly hygroscopic materials[17][13]No special storage needed[2]
Mechanical Properties
Tensile strength (XY)MPa59.9 ± 0.8 printed XY, ISO 527 (Fiberon PET-GF15)[1]46.6 ± 1.3 filament tensile yield (Prusament, ISO 527) — more than double the carbon-fibre grade's 21[2][9]
Young's modulusMPa4144 ± 133 printed XY, ISO 527 (Fiberon PET-GF15)[1]Not documented
Elongation at break%4.0 ± 0.5 printed XY, ISO 527 (Fiberon PET-GF15)[1]Not documented
Flexural strengthMPa104.2 ± 2.4 printed XY, ISO 178 (Fiberon PET-GF15)[1]Not documented
Flexural modulusMPa3705 ± 85 printed XY, ISO 178 (Fiberon PET-GF15)[1]Not documented
Charpy impact, notchedkJ/m²8.7 ± 0.6 printed XY, ISO 179, notched (Fiberon PET-GF15)[1]7.9 ± 0.4 printed horizontal and 9.9 ± 0.8 printed vertical XZ (ISO 179-1, notched)[2]
Other impact dataCharpy unnotched 27.2 ± 2.0 printed XY (Fiberon PET-GF15, ISO 179)[1]Not documented
Layer adhesion / Z tensileMPa48.2 ± 0.3 printed Z, ISO 527 (Fiberon PET-GF15)[1]Not documented
Brittleness1–5Brittle — snaps with little warning; elongation 4.0 % in XY and 2.6 % in Z[1]Moderate[2]
Hardness (scale-specific)Shore A / Shore D / RockwellNot documentedRockwell R102 (and M95) on extruded unfilled PP stock (ASTM D785); no figure is published for a glass-fibre PP filament[18]
Creep resistance / sustained load1–5Below average — no GF-grade creep test; the CF grades sagged to 14.8–16.7 mm over 5 days at 1.25 kg against 17.1–20.4 mm unfilled[19][20][21]Not documented
Fatigue / repeated-flex resistance1–5Below average — no GF-grade S-N curve; elongation at break falls to 4.0 % in XY against 5.2–9.3 % unfilled[1][22]Not documented
Elasticity / flexibility1–5Rigid[1]Rigid[2]
Z strength as % of XY%80 (Fiberon PET-GF15, printed Z against XY tensile)[1]Not documented
Thermal Properties
HDT at 0.45 MPa°C81.6 as printed, 133.7 after annealing (ISO 75, 0.45 MPa)[1]138.3 (ISO 75, 0.45 MPa)[2]
HDT at 1.8 MPa°C71.8 as printed, 87.3 after annealing (ISO 75, 1.8 MPa)[1]112.6 (ISO 75, 1.8 MPa)[2]
Glass transition (Tg)°C59.5 (DSC)[1]Not documented
Melting point / Vicat°C231.6 melting (DSC); Vicat 232.6 (ISO 306)[1]Not documented
Annealing responseAnnealing lifts HDT at 0.45 MPa from 81.6 to 133.7 °C[1]Not documented
Thermal expansion (CTE)µm/m·K20 along the print bead and 63–74 in the build direction at 30 °C (30 wt% GF, large-format printed, TMA)[23]Not documented
Flammability / UL 94UL 94 HB at 1.5 mm (Fiberon PET-GF15)[1]Not documented
Environment & Chemical
Chemical resistanceWithstands acids, alkalis, oils and UV exposure[13]Excellent against acids, alkalis and most solvents[11]
Water / humidity resistance in service1–5Not documentedExcellent — essentially unaffected[2]
Food contactNot certified for food contact as filament[13]Not documented
Biodegradability / compostabilityNot biodegradable[13]Not documented
RecyclabilityNot accepted in household plastic collection[13]Not documented
Electrical & ESD propertiesSurface resistivity above 10¹² ohm — insulating (Fiberon PET-GF15, ANSI/ESD S11.11)[1]Not documented
Health & Safety
Fume toxicity1–5Moderate — measurable VOCs and UFPs, ventilation advised[24]Low hazard — minimal VOC and particle emission. Inferred: no polyolefin was among the nine filaments in the Azimi chamber study, so this is a family-level judgement rather than a measurement[24]
Ventilation / filtration requirement1–5Open a window / occasional ventilation[24]Open a window / occasional ventilation. Inferred — no polyolefin was measured in the chamber study[24]
Dust & fibre handling hazardGlass fibre is bound in the matrix; avoid inhaling sanding dust[1]Glass fibre is bound in the matrix; avoid inhaling sanding dust[2]
Post-Processing
Sanding & machiningSands poorly — the material is tough and gums rather than powders[16]Not documented
Gluing & solvent weldingCyanoacrylate; no common solvent welds PETG cleanly[16]Not documented
Vapour / chemical smoothingNo practical vapour smoothing[16]Not documented
Support material pairingPrints its own supports; Polymaker rates PolyDissolve S1 for PETG[16]Not documented
Solvents & Solubility
Soluble inNo common workshop solvent; dichloromethane — a carcinogen — dissolves the matrix surface, 1,2-dichloroethane destroys it in a week.[25][26]None at room temperature; chloroform dissolves the matrix at 60 °C and xylene at about 118 °C, leaving the fibre.[27][28]
Softened or crazed byAcetone (+16 % weight over 1 year at 23 °C), ethyl acetate, toluene and DMF swell and soften it; methanol crazes it.[25]Xylene, decalin, CCl4 and chlorobenzene are heavily absorbed at 20 °C; oleum, chlorosulphonic acid and bromine destroy it.[27]
Solvent welding & smoothing agentDichloromethane reaches only the resin, so the fibre is left standing proud of the surface. Controlled carcinogen.[26]None — nothing softens PP at room temperature, so joints have to be welded thermally rather than chemically.[27]

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. Fiberon PET-GF15 Technical Data Sheet V1.0 Polymaker · 2026-08 · tds
  2. Prusament PP Glass Fiber Technical Datasheet v1.0 Prusa Polymers · 2024-11 · tds
  3. Prusament PP Glass Fiber — material page Prusa Polymers · 2026-08 · doc
  4. ELEGOO product catalogue ELEGOO · 2026-08 · vendor
  5. Polymaker product catalogue Polymaker · 2026-08 · vendor
  6. BASF Ultrafuse PP GF30 Black 2.85 mm 2.200 g igo3d · 2026-08 · vendor
  7. BCN3D PP GF30 Black 2.85 mm 700 g igo3d · 2026-08 · vendor
  8. Prusa Prusament PP Glass Fiber Natural (NFC), 1.75 mm / 850 g 3DJAKE · 2026-08 · vendor
  9. Prusament PP Carbon Fiber Technical Datasheet v1.0 Prusa Polymers · 2024-11 · tds
  10. Polypropylene — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  11. PP — material basics Polymaker Wiki · 2026-08 · doc
  12. Prusament PETG Technical Datasheet v1.1 Prusa Polymers · 2022-02 · tds
  13. PETG — material basics Polymaker Wiki · 2026-08 · doc
  14. Max volumetric speed Prusa Knowledge Base · 2026-08 · doc
  15. Composite materials filled with carbon, kevlar or glass Prusa Knowledge Base · 2026-08 · doc
  16. PET and PETG — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  17. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  18. TECAFINE PP natural — stock shape properties Ensinger · 2026-08 · tds
  19. Extrudr PETG vs PCTG vs XPETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  20. Prusament PETG-CF vs PETG V0 vs PETG — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  21. BambuLab PETG Basic vs Translucent vs PETG-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  22. Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
  23. Effects of Fiber Orientation on the Coefficient of Thermal Expansion of Fiber-Filled Polymer Systems in Large Format Polymer Extrusion-Based Additive Manufacturing Materials 15(8):2764 · 2022-04 · paper
  24. 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
  25. Eastman Spectar copolyester — Chemical resistance (unstressed bars, 1 year at 23 °C) Eastman Chemical Company · 2026-08 · tds
  26. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc
  27. Pro-fax and Moplen polypropylene — Chemical Resistance Guide (20, 60 and 100 °C) LyondellBasell · 2026-08 · tds
  28. US 5,278,282 Polymer recycling by selective dissolution — xylene dissolution temperatures Nauman & Lynch, Rensselaer Polytechnic Institute · 1994-01 · paper