PMP
also TPX
PMP (polymethylpentene, TPX) is a low-density, highly transparent polyolefin with low dielectric loss and good heat and chemical resistance.
Reference datasheet — PMP is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
PMP grades and fills
PMP is supplied in 2 conditions, soft to hard.
Compare all 2 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Flexible / impact-modified soft grade | Pick when flexibility, elongation and low-temperature toughness matter more than stiffness and HDT (soft tubing, flexible films, elastic parts). | 11 | 15 | 200 | 50 Shore D |
High-heat / extrusion & film grade | Choose for release film, tubing and parts needing the highest HDT and best transparency retention at temperature. | 26 | 27 | 15 | 72 Shore D |
Supply forms, finishes and certifications
Ways PMP is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
MED | Medical / food-contact grade | Certification |
UV | UV / heat-stabilized grade | Grade option |
NATDefault | Unfilled / natural injection-molding grade | Standard supply |
What is PMP?
PMP (polymethylpentene, TPX) is a low-density, highly transparent polyolefin with low dielectric loss and good heat and chemical resistance. It is used where microwave transparency, high-temperature clarity or clean release are required, in natural, medical and UV-stabilised grades supplied as moulding pellets, sheet and release film, with service to 150 °C. Strength is modest at 25 MPa tensile and 20 % elongation, walls are low in stiffness, and the very low surface energy makes printing and bonding unreliable without pretreatment. COC is the nearest alternative when higher stiffness is needed. PMP has a density of 0.83 g/cm³ (0.0301 lb/in³), lighter than 83% of polymer grades. Its glass-transition temperature is 30°C (86 °F). PMP has a yield strength of 24 MPa (3.48 ksi) and a tensile strength of 25 MPa (3.63 ksi) — weaker than 76% of polymer grades. Elongation at break is 20% and the elastic modulus is 1.5 GPa (0.218 Msi).
What is PMP used for?
- microwaveable food containers
- laboratory glassware substitutes
- medical syringes
- release films
- RF/microwave transparent components
Advantages
- Low moisture uptake — 0.01%, better than 97% of polymer grades
- Lightweight — 0.83 g/cm³ (0.0301 lb/in³), better than 83% of polymer grades
- High service temperature — 150°C (302 °F), better than 79% of polymer grades
- Polishes to a fine finish — 70/100, better than 77% of polymer grades
Limitations
- High mold shrinkage — 2%, worse than 81% of polymer grades
- Low strength — 24 MPa (3.48 ksi), worse than 76% of polymer grades
- Degrades in UV without stabilisers — 25/100, worse than 76% of polymer grades
- Poor heat conductor — 0.17 W/m·K (0.0982 BTU/hr·ft·°F), worse than 75% of polymer grades
PMP properties
Typical room-temperature values; bars are the position among polymer grades.
Physical7
PMP has a density of 0.83 g/cm³ (0.0301 lb/in³), lighter than 83% of polymer grades. Its glass-transition temperature is 30°C (86 °F).
Mechanical11
PMP has a yield strength of 24 MPa (3.48 ksi) and a tensile strength of 25 MPa (3.63 ksi) — weaker than 76% of polymer grades. Elongation at break is 20% and the elastic modulus is 1.5 GPa (0.218 Msi).
Thermal11
PMP is rated for continuous service to 150°C (302 °F). It conducts heat at 0.17 W/m·K (0.0982 BTU/hr·ft·°F), worse than 75% of polymer grades. Thermal expansion is 117 µm/m·K (65 µin/in·°F).
Electrical7
PMP is an electrical insulator with a dielectric strength of 27 kV/mm (685.8 V/mil) and a resistivity of 1×10¹⁴ Ω·m.
Chemical & Environmental3
Corrosion resistance is excellent (88/100), better than 74% of polymer grades. UV resistance is poor.
Sustainability4
Producing a kilogram of PMP takes about 105 MJ of energy and emits 4.2 kg of CO₂ — more than 54% of polymer grades. Typical recycled content is 0%.
Manufacturability8
PMP's machinability is good (65/100, better than 66% of polymer grades); weldability fair (50/100); formability good (60/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the polymer family
Yield strength against density for every polymer grade FabDigit runs. PMP is highlighted; hover a dot for its name, or open the interactive family chart.
Working with PMP
Is PMP easy to machine?
Machines like a soft polyolefin — sharp positive-rake tools, high speed, low feed and air/mist cooling; parts are low-stiffness so support thin walls and expect springback.
Can PMP be welded?
Hot-plate, hot-gas and ultrasonic welding work with PMP filler only; the low-energy surface makes adhesive bonding unreliable without flame/plasma or corona treatment.
Can PMP be formed, bent or molded?
Dry lightly, mold at 280–300 °C melt with 40–90 °C tool; allow 1.5–3 % shrinkage and design for its excellent natural mold release (no external release agents needed).
PMP chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| linear α-olefin comonomer (e.g. 1-decenecopolymer content tunes stiffness, clarity and Tm | 0 – 10 | 4 |
| antioxidant / stabilizer packagephenolic + phosphite; UV grades add HALS | 0.1 – 1 | 0.3 |
| 4-methyl-1-pentene monomer unitspoly(4-methyl-1-pentene) backbone | ≥ 90 (balance) |
What surface finishes work on PMP?
Take gloss and optical quality directly from a polished tool; painting, printing or metallizing requires surface pre-treatment because of the very low surface energy.
Equivalent designations
Standards and trade names that resolve to PMP in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Trade names
- TPX
How much does PMP cost?
PMP is a high-cost polymer ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
PMP — frequently asked
What is PMP used for?
PMP is typically used for microwaveable food containers, laboratory glassware substitutes, medical syringes, release films and RF/microwave transparent components. In short: low-density transparent polyolefin; 150 °C service temperature; excellent natural mould release.
What is the yield strength of PMP?
PMP has a typical yield strength of 24 MPa (3.48 ksi) and a tensile strength of 25 MPa (3.63 ksi) — weaker than 76% of polymer grades. Strength varies by condition: see the 2 listed tempers.
Is PMP easy to machine?
Reasonably — machinability is rated good (65/100, better than 66% of polymer grades). Machines like a soft polyolefin — sharp positive-rake tools, high speed, low feed and air/mist cooling; parts are low-stiffness so support thin walls and expect springback.
Can PMP be welded?
With care — weldability is rated fair (50/100). Hot-plate, hot-gas and ultrasonic welding work with PMP filler only; the low-energy surface makes adhesive bonding unreliable without flame/plasma or corona treatment.
What surface finishes work on PMP?
Take gloss and optical quality directly from a polished tool; painting, printing or metallizing requires surface pre-treatment because of the very low surface energy.
Can PMP be formed, bent or molded?
Dry lightly, mold at 280–300 °C melt with 40–90 °C tool; allow 1.5–3 % shrinkage and design for its excellent natural mold release (no external release agents needed).
What is the maximum service temperature of PMP?
PMP is rated for continuous use to about 150°C (302 °F), and briefly to 200°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does PMP cost?
PMP is a high-cost polymer ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- TPX (poly-4-methylpentene-1) grade and property data — Mitsui Chemicals (2023)
- Polymer Handbook / Handbook of Plastics, Elastomers and Composites — polyolefin data — Wiley / McGraw-Hill (2006)
- CAMPUS / UL Prospector thermoplastic property records for PMP — CAMPUS, UL Solutions (2024)
- ISO 527 / ISO 178 / ISO 75 / ASTM D150 test methods referenced for reported values — ISO / ASTM (2019)
- 1688 SMM TPX/PMP (2026)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.