3D Printing Info

Filament comparison

PE vs PP

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

Polyethylene (PE) guidePolypropylene (PP) guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PE comparisonsMore PP comparisons
PE vs PP — documented properties and sources
PropertyPolyethylene (PE)POLYOLEFINPolypropylene (PP)POLYOLEFIN
Market snapshot
Listing priceUSD/kg; dated snapshots$87.72/kg median; $87.72–$87.72/kg across 1 dated product listings$46.56/kg median; $31.99–$53.00/kg across 4 dated product listings
Identity & Market
Base polymer / chemistryPolyethylene — the simplest polyolefin, non-polar and highly crystalline. The one retailed filament grade, Spectrum HDPE, uses what Spectrum calls Low Warp technology and is denser and stiffer than plain HDPE[1][2]Polypropylene — a semi-crystalline polyolefin with no polar groups, so it neither absorbs water nor bonds to most bed surfaces[3][4]
Densityg/cm³1.10 (Spectrum HDPE filament, ISO 1183) against 0.95 for extruded HDPE stock — the filament is a modified formulation[1][2]0.91 (Prusa PP composite, ISO 1183) — the lightest common filament[5]
Typical priceUSD/kg1 kg-equivalent spools cluster near 88[6]1 kg-equivalent spools span 27–53; the middle of the market is about 44[7][8][9][10]
Price range across brandsUSD/kg87.72 — Spectrum's 500 g spools at 3DJAKE are the only PE filament listing found[6]27–53 across brands; Reli3D 32 on Amazon, SUNLU 44 at 0.8 kg, Fiberlogy 49 at 750 g, IEMAI 3D 53, and the 3DJake PP listing spans 27–49[7][11][8][9][10]
Market availability1–5Niche, a handful of specialist brands — Spectrum HDPE in six colours is the only PE filament in the 3DJAKE and igo3d product sitemaps, at MatterHackers or at Printed Solid, but it is a normal stocked item rather than a special order[12][13][14][6]Available from several mainstream brands[11][8][7]
Spool sizes & diameters1.75 mm; 500 g spools in six colours[6][12]1.75 and 2.85 mm; 0.75 kg spools are common[8]
Typical applicationsChemically resistant containers, packaging prototypes and consumer goods where HDPE is the production material[1]Living hinges, chemical-resistant containers, automotive clips and packaging prototypes[3]
Printing Parameters
Nozzle temperature°C240-290 (Spectrum HDPE)[1]210–230 (Braskem-type PE/PP window); Formfutura's Centaur PP melts at 205 ± 15 °C[3]
Bed temperature°C80-100 (Spectrum HDPE)[1]Not documented
Enclosure / chamber requirement1–5Enclosure recommended — Spectrum recommends a closed chamber for larger prints[1]Enclosure recommended — Simplify3D lists an enclosure as a hardware requirement and Polymaker advises one below 70 °C ambient to stop warping and cracking[15][4]
Part cooling fan0-50 % part cooling (Spectrum HDPE)[1]Part cooling fan required (Simplify3D)[15]
Bed surface & adhesion aidSpectrum states no adhesive is necessary for its low-warp HDPE, depending on geometry[1]Packing tape, a polypropylene sheet, or a PP-specific adhesive such as Magigoo PP — ordinary PLA and ABS adhesives do not hold it[15][4]
Warping tendency1–5Moderate — needs adhesion aid or draught shield. Spectrum's low-warp grade is sold as printable on desktop machines, which is not true of plain polyethylene[1]High — enclosure needed for reliable large parts; PP's crystallinity drives shrinkage and Prusa recommends a brim on its PP grades[5][16]
Bed-adhesion difficulty1–5Needs the right surface or a thin adhesive; Spectrum states no adhesive is necessary but recommends a closed chamber for large parts[1]Very difficult — special plates or slurry required. PP bonds to almost nothing; a polypropylene-specific tape or adhesive is the normal answer[5][4]
Stringing / oozing tendency1–5Not documentedSlight — Polymaker advises 1–2 mm retraction at 20–30 mm/s[4]
Overall printing difficulty1–5Intermediate — dry filament and a tuned profile; Spectrum sells the grade as desktop-printable with no dry box and no hardened nozzle[1]Advanced — enclosure, hardware upgrades, tuning; bed adhesion is the whole problem[4][5]
Hardware Wear & Reliability
Nozzle hardness required1–4Brass fine indefinitely — Spectrum states a ruby or hardened nozzle is not required[1]Brass fine indefinitely for unfilled grades — Simplify3D states no special hotend is required[15]
Abrasiveness1–5Non-abrasive[1]Non-abrasive when unfilled[15]
Nozzle clog risk1–5Low — Spectrum lists no drybox and no ruby or hardened nozzle for HDPE, and very low moisture absorption[1]Low — Simplify3D lists no special hotend requirement for PP and clogging is not among its listed drawbacks[17][15]
Heat-creep / jam sensitivity1–5Not documentedSlightly sensitive[15]
Hotend requirementNot documentedNo special hot-end required (Simplify3D)[15]
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Negligible (<0.1 % EMC) — Spectrum lists very low moisture absorption and no dry box[1]Negligible (<0.1 % EMC) — Prusa measures 0.03 % in 24 h and 0.04 % in 7 days on its PP composite, the lowest figures it publishes for any filament[5]
Equilibrium moisture content at ~50 % RH%Not documented0.03 after 24 h and 0.04 after 7 days at 24 °C / 22 % RH (Prusa Polymers, measured on its PP composite)[5]
Drying temperature & timeNo drying step published; Spectrum lists a dry box as not required[1]No drying step is published for PP; uptake is below the level that affects printing[5]
Symptoms when wetNot documentedBubbling and popping at the nozzle; Polymaker still advises a 70 °C dry for 4–6 h despite the low uptake[4]
Effect of moisture on strengthNot applicable in practice — Spectrum lists very low moisture absorption and no drybox requirement for HDPE[1]Not applicable in practice — with equilibrium uptake at 0.04 %, there is no moisture-driven strength loss to measure. Polymaker's sensitivity tiers put polyolefins below even PLA[5][17]
Storage requirementStore dry at 18-25 °C out of sunlight; Spectrum quotes a 24-month shelf life[1]No special storage needed[5]
Mechanical Properties
Tensile strength (XY)MPa29 at break (Spectrum HDPE, ISO 527; specimen type not stated) against 25.5 at yield on extruded HDPE stock (ASTM D638, from 3700 psi)[1][2]12 at yield (Formfutura Centaur PP, ASTM D638)[3]
Young's modulusMPa3500 (Spectrum HDPE, ISO 527) against 965 on extruded HDPE stock (ASTM D638, from 140,000 psi) — the filament grade is nearly four times stiffer than plain polyethylene[1][2]724 on extruded PP stock (ASTM D638; converted from 105,000 psi)[18]
Elongation at break%18 at break (Spectrum HDPE, ISO 527) against above 100 on extruded stock (ASTM D638)[1][2]Above 600 at break (Formfutura Centaur PP, ASTM D638)[3]
Flexural strengthMPa27.6 on extruded HDPE stock (ASTM D790; converted from 4000 psi)[2]31.0 on extruded PP stock (ASTM D790; converted from 4500 psi)[18]
Flexural modulusMPa3200 (Spectrum HDPE, ISO 178) against 965 on extruded stock (ASTM D790, from 140,000 psi)[1][2]402 flexural modulus (Formfutura Centaur PP, ASTM D790) — an order of magnitude below any rigid filament[3]
Other impact dataCharpy 10 kJ/m2 (Spectrum HDPE, ISO 179-1; notch condition not stated); Izod 104 J/m on extruded stock, converted from 1.94 ft-lb/in (ASTM D256)[1][2]Izod notched 112 J/m on extruded PP stock, converted from 2.1 ft-lb/in (ASTM D256)[18]
Brittleness1–5Tough — absorbs impact, yields before breaking; 18 % elongation at break on the filament and above 100 % on extruded stock[1][2]Very ductile — bends far before failing[3]
Hardness (scale-specific)Shore A / Shore D / RockwellShore D 67 and Rockwell R54 on extruded HDPE stock (ASTM D2240, D785); Spectrum quotes Rockwell 80 HRM for its filament (ISO 2039-2)[2][1]Rockwell R102 (and M95) on extruded PP stock (ASTM D785)[18]
Creep resistance / sustained load1–5Not documentedBelow average[3]
Fatigue / repeated-flex resistance1–5Good — Spectrum lists outstanding abrasion and crack resistance for its HDPE, but no repeated-flex or fatigue test data was found for any PE filament[1]Excellent — living hinges viable, the classic polypropylene application[3]
Elasticity / flexibility1–5Slightly flexible in thin sections — Spectrum's low-warp grade has a 3.5 GPa tensile modulus; plain extruded HDPE at 965 MPa is genuinely semi-flexible[1][2]Semi-flexible[3]
Thermal Properties
HDT at 0.45 MPa°C75 on extruded HDPE stock (ASTM D648 at 66 psi; converted from 167 °F)[2]74 on extruded PP stock (ASTM D648 at 66 psi; converted from 165 °F)[18]
Melting point / Vicat°CNot documented205 ± 15 melting (Formfutura Centaur PP)[3]
Continuous service temperature°C110 stated as heat resistance by Spectrum with no test standard given; extruded stock is rated 120 long-term maximum (converted from 248 °F) and brittle below -76[1][2]Bounded by a melting point of 205 ± 15 °C and by the 158 °C heat deflection of the carbon-filled grade; no loaded-bar service figure is published for unfilled PP[3][5]
Thermal expansion (CTE)µm/m·K117 (extruded HDPE stock, ASTM D696; source states 6.5e-5 in/in/°F)[2]Not documented
Flammability / UL 94Not documentedFlammable; no UL 94 rating published for the grades surveyed[5]
Environment & Chemical
UV resistance1–5Moderate — a season or two. Spectrum describes its HDPE as UV-stable and weather-resistant but publishes no exposure data[1]Months outdoors before embrittlement — unstabilised polypropylene chalks under UV[4]
Chemical resistanceExcellent chemical resistance to acids, bases, oils and solvents (Spectrum); Ensinger lists broad chemical compatibility for HDPE stock[1][2]Excellent against acids, alkalis and most solvents — the usual reason to choose PP[4]
Water / humidity resistance in service1–5Excellent — essentially unaffected; Ensinger lists low moisture absorption for HDPE stock and Spectrum very low absorption for the filament[1][2]Excellent — essentially unaffected[5]
Food contactNot documentedPolypropylene is a common food-packaging polymer, but no filament here carries a food-contact certification[4]
Biodegradability / compostabilityNot documentedNot biodegradable[4]
RecyclabilitySpectrum states the filament is fully recyclable; HDPE is resin code 2[1]Mechanically recyclable as resin code 5, but printed waste is not accepted in household collection[4]
Health & Safety
Fume toxicity1–5Not documentedLow 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[19]
Ventilation / filtration requirement1–5Not documentedOpen a window / occasional ventilation. Inferred — no polyolefin was measured in the chamber study[19]
Post-Processing
Sanding & machiningEasy to machine — Ensinger lists machinability as a headline property of HDPE stock[2]Sands poorly — the waxy surface loads abrasive paper[15]
Painting & finishingNot documentedPaint and adhesives do not key to untreated PP; flame or plasma treatment is normally needed first[4]
Gluing & solvent weldingNot documentedNothing common bonds untreated PP; flame or plasma treatment is needed before adhesives key[4]
Vapour / chemical smoothingNot documentedNo practical vapour smoothing[15]
Support material pairingNot documentedPrints its own supports; no soluble support is rated for PP[15]
Dimensional accuracy & detailSpectrum lists a shiny surface finish and no adhesive requirement; shrinkage remains the limit on large flat parts[1]Shrinkage and warping dominate; the low modulus means parts flex rather than hold tolerance[5]
Solvents & Solubility
Soluble inNone at room temperature; xylene dissolves HDPE at about 105 °C and LDPE at 75 °C. Hot decalin does the same.[20][21]None at room temperature; chloroform dissolves it at 60 °C and xylene at about 118 °C — the xylene-solubles route.[22][20]
Softened or crazed byToluene, xylene, styrene, chloroform, dichloromethane, MEK and trichloroethylene are all unsatisfactory at 21 °C.[21]Xylene, decalin, CCl4 and chlorobenzene are heavily absorbed at 20 °C; oleum, chlorosulphonic acid and bromine destroy it.[22]
Solvent welding & smoothing agentNone — polyethylene has no room-temperature solvent, so joints are made by heat welding.[21][20]None — nothing softens PP at room temperature, so joints have to be welded thermally rather than chemically.[22]

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. Spectrum HDPE Technical Data Sheet Spectrum Filaments · 2025-10 · tds
  2. TECAFINE HDPE natural — stock shape properties Ensinger · 2026-08 · tds
  3. Centaur PP Technical Data Sheet Formfutura · 2026-08 · tds
  4. PP — material basics Polymaker Wiki · 2026-08 · doc
  5. Prusament PP Carbon Fiber Technical Datasheet v1.0 Prusa Polymers · 2024-11 · tds
  6. Spectrum HDPE Traffic Black, 1.75 mm / 500 g 3DJAKE · 2026-08 · vendor
  7. SUNLU product catalogue SUNLU · 2026-08 · vendor
  8. Fiberlogy PP Natural — product page 3DJake International · 2026-08 · vendor
  9. Reli3D Low Warp PP Filament 1.75 mm 1 kg Black — Amazon listing Amazon.com · 2026-08 · vendor
  10. IEMAI 3D PP 3D Printing Filament — store page IEMAI 3D · 2026-08 · vendor
  11. PP filament listing 3DJake International · 2026-08 · vendor
  12. 3DJAKE product catalogue 3DJAKE · 2026-08 · vendor
  13. igo3d product sitemap (17452 product URLs) igo3d · 2026-08 · vendor
  14. Printed Solid product catalogue Printed Solid · 2026-08 · vendor
  15. Polypropylene — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  16. Prusament PP Glass Fiber Technical Datasheet v1.0 Prusa Polymers · 2024-11 · tds
  17. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  18. TECAFINE PP natural — stock shape properties Ensinger · 2026-08 · tds
  19. 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
  20. US 5,278,282 Polymer recycling by selective dissolution — xylene dissolution temperatures Nauman & Lynch, Rensselaer Polytechnic Institute · 1994-01 · paper
  21. HDPE Chemical Resistance Guide (21 °C and 60 °C) INEOS Olefins & Polymers USA · 2026-08 · tds
  22. Pro-fax and Moplen polypropylene — Chemical Resistance Guide (20, 60 and 100 °C) LyondellBasell · 2026-08 · tds