3D Printing Info

Filament comparison

PSU vs HT soluble

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

PSU guideHigh-temperature support guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PSU comparisonsMore HT soluble comparisons
PSU vs HT soluble — documented properties and sources
PropertyPSUHIGHTEMPHigh-temperature supportSUPPORT
Market snapshot
Listing priceUSD/kg; dated snapshots$168.00/kg median; $168.00–$168.00/kg across 1 dated product listings$209.00/kg median; $100.00–$290.00/kg across 4 dated product listings
Identity & Market
Base polymer / chemistryPolysulfone — the lowest-temperature and cheapest of the sulfone family[1]Break-away support compounded to survive high-temperature print chambers; 3DXTech sells separate grades for PC/ABS and for the PAEK and PEI class[2][3]
Densityg/cm³1.24 (ISO 1183)[1]1.37 (3DXTech THERMAX HTS1, ISO 1183)[2]
Typical priceUSD/kg1 kg-equivalent spools cluster near 250[4]1 kg-equivalent spools cluster near 168[4]
Price range across brandsUSD/kg168-250 across formats; 250 g spool $42 (168/kg), 500 g $125 (250/kg) — 3DXTech is the only filament supplier found[4]100–290 across grades; 3DXTech THERMAX MTS1 100 at 2 kg, HTS2 168 at 250 g, HTS1 250 at 500 g, IEMAI 3D HT-SP 290 at 1 kg[4][5]
Market availability1–5Special order, 1–2 makers worldwide[4]Niche, a handful of specialist brands[4][5]
Spool sizes & diameters1.75 mm; 250 g and 500 g spools[4]1.75 mm; 250 g, 500 g, 1 kg and 2 kg spools[4]
Typical applicationsTransparent high-temperature housings, medical trays and hot-water fittings[1]Support for PEEK, PEI and PC-class prints, where PVA and PLA-based supports would decompose[2][3]
Printing Parameters
Bed temperature°C120–140 (3DXTech)[1]Not documented
Enclosure / chamber requirement1–5Actively heated chamber required[6][7]Actively heated chamber required — it is used inside high-temperature builds[2]
Overall printing difficulty1–5Expert / industrial hardware only[6][7]Expert / industrial hardware only[2]
Extruder requirementNot documentedA dual-extruder machine rated for high-temperature materials; 3DXTech states the grade is intended for dual-extruder printers designed to print high-temp materials[8]
Hardware Wear & Reliability
Nozzle hardness required1–4Brass fine indefinitely for unfilled grades, but brass softens near these nozzle temperatures — hardened or plated hot ends are the norm[6]Brass fine indefinitely[2]
Abrasiveness1–5Non-abrasive when unfilled[1]Non-abrasive[2]
Nozzle clog risk1–5Moderate — needs dry filament and a clean nozzle; 3DXTech lists no special nozzle concerns but a mandatory 120 °C pre-dry before every print[9]Moderate — needs dry filament and a clean nozzle; 3DXTech lists no special nozzle concerns but a mandatory 120 °C pre-dry for HTS1 and 80 °C for MTS1[8][10]
Moisture Behaviour
Equilibrium moisture content at ~50 % RH%0.30 in 24 h on extruded stock (ASTM D570)[11]Not documented
Effect of moisture on strengthNo dry-versus-conditioned figures are published; 3DXTech mandates a 120 °C, 4 h pre-dry before every print because trapped water flashes to steam at these nozzle temperatures[9]No dry-versus-conditioned figures are published; 3DXTech mandates a 120 °C, 4 h pre-dry for HTS1 and 80 °C for MTS1 because trapped water flashes to steam at these nozzle temperatures[8][10]
Mechanical Properties
Tensile strength (XY)MPa52 (printed XY, ISO 527, 3DXTech); 81 at break on extruded stock (ASTM D638)[1][11]Not documented
Young's modulusMPa2100 (printed XY, ISO 527)[1]Not documented
Elongation at break%8 (printed XY, ISO 527) against 50 on extruded stock — nearly three times PPSU's printed 3 %[1][12][11]Not documented
Flexural strengthMPa87 (printed XY, ISO 178)[1]Not documented
Flexural modulusMPa2050 (printed XY, ISO 178)[1]Not documented
Other impact dataIzod notched 69 J/m on extruded PSU stock, converted from 1.3 ft-lb/in (ASTM D256)[11]Not documented
Brittleness1–5Moderate[1]Not documented
Hardness (scale-specific)Shore A / Shore D / RockwellRockwell M120 on extruded PSU stock (ASTM D785)[11]Not documented
Creep resistance / sustained load1–5Good. Ensinger lists high creep resistance as a headline property of extruded PSU stock, which is rated to 173 °C heat deflection at 1.8 MPa[11]Not documented
Elasticity / flexibility1–5Rigid[1]Not documented
Wear resistance & frictionNot documented3DXTech marks tensile strength, modulus and elongation as not applicable for its support grades — they are not characterised as structural materials[2]
Thermal Properties
HDT at 0.45 MPa°C172 (printed XY, ISO 75 at 0.45 MPa, 3DXTech); 181 on extruded stock, converted from 358 °F at 66 psi[1][11]Not documented
HDT at 1.8 MPa°C174 on extruded PSU stock, converted from 345 °F at 264 psi (ASTM D648)[11]205 (THERMAX HTS1, printed XY, ISO 75 at 1.8 MPa)[2]
Glass transition (Tg)°C187 (DSC, 3DXTech) and 185 on extruded stock (ASTM D3418), against 230 for PPSU[1][12][11]225 (3DXTech THERMAX HTS1, DSC) — high enough to stay solid inside a PEI or PEEK build[2]
Continuous service temperature°C141 long-term service on extruded PSU stock, converted from 285 °F[11]Not documented
Thermal expansion (CTE)µm/m·K55.8 (extruded PSU stock, ASTM D696; source states 3.1e-5 in/in/°F)[11]Not documented
Flammability / UL 94UL 94 V-0 on extruded PSU stock[11]Not documented
Environment & Chemical
Electrical & ESD propertiesSurface resistance above 10¹³ ohm/sq — an insulator (IEC 60093)[1]Surface resistance above 10^13 ohm/sq on all three THERMAX support grades (ASTM D257) — insulating[2][13][3]
Health & Safety
Fume toxicity1–5Moderate — measurable VOCs and UFPs, ventilation advised. None of these polymers was in the chamber study, and all are processed far above the temperatures it covered[14]Low hazard — minimal VOC and particle emission; none of these materials was in the chamber study[14]
Ventilation / filtration requirement1–5Ventilated room or enclosure recommended[14]Open a window / occasional ventilation[14]
Post-Processing
Support material pairingNot documentedThis is the support material. MTS1 is matched to PC/ABS and PC; HTS1 and HTS2 to the higher-temperature classes[3][2]
Solvents & Solubility
Soluble inChlorinated hydrocarbons — dichloromethane, chloroform — dissolve polysulfone; ketones and esters attack it as well.[15][16]Aqueous alkali, not water: IEMAI specifies an alkaline bath in an ultrasonic cleaner until the support dissolves.[5]
Softened or crazed byAcetone, MEK, ethyl acetate, benzene and toluene craze or stress-crack it; methanol and isopropanol only marginally.[16][15]Not documented
Solvent welding & smoothing agentDichloromethane cement welds PSU and NMP softens residual resin. Both are laboratory reagents.[15]None — the alkaline bath dissolves the support rather than welding anything.[5]

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. ThermaX PSU Technical Data Sheet v3 3DXTech · 2026-08 · tds
  2. THERMAX HTS1 Break Away Support Technical Data Sheet v1.0 3DXTech · 2026-08 · tds
  3. THERMAX MTS1 Break Away Support Technical Data Sheet v1.0 3DXTech · 2026-08 · tds
  4. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  5. IEMAI 3D HT-SP alkaline-soluble support filament — store page IEMAI 3D · 2026-08 · vendor
  6. Prusament PEI 1010 Technical Datasheet v1.0 Prusa Polymers · 2024-09 · tds
  7. Prusament PEI 1010 — material page Prusa Polymers · 2026-08 · doc
  8. THERMAX HTS1 — product page 3DXTech · 2026-08 · vendor
  9. THERMAX PSU — product page (print recommendations) 3DXTech · 2026-08 · doc
  10. THERMAX MTS1 — product page 3DXTech · 2026-08 · vendor
  11. TECASON S natural (PSU) — stock shape properties Ensinger · 2026-08 · tds
  12. ThermaX PPSU Technical Data Sheet v3 3DXTech · 2026-08 · tds
  13. THERMAX HTS2 Break Away Support Technical Data Sheet v1.0 3DXTech · 2026-08 · tds
  14. 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
  15. Radel PPSU, Veradel PESU, Acudel modified PPSU Design Guide — environmental stress cracking tables Solvay Specialty Polymers · 2026-08 · tds
  16. Chemical resistance — resistance of Ensinger plastics to chemicals (DIN 50 014, 23/50) Ensinger · 2026-08 · tds