PP-R
A random-copolymer PP with ethylene units statistically distributed in the chain, giving better clarity, low-temperature impact resistance and long-term hoop-stress performance than homopolymer; the standard resin for hot/cold water piping systems.
Reference datasheet — PP-R 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.
PP-R grades and fills
PP-R is supplied in 6 conditions, soft to hard.
Compare all 6 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Impact-modified PP-R (elastomer-toughened) for cold-climate / drainage… | Choose the elastomer-toughened compound for sub-0 °C impact in drainage and cold-climate piping, accepting slightly lower stiffness and heat resistance; 22 MPa tensile with 700% elongation. | 21 | 22 | 700 | 58 Shore D |
Mineral (talc / CaCO₃) filled PP-R | Use talc or CaCO₃ filled stock as a low-cost stiffening middle layer or non-pressure part; modulus rises to 1.7 GPa while impact toughness and long-term hydrostatic performance fall. | 24 | 40 | ||
Injection-moulding grade PP-R for fittings | Pick for injection moulding of complex fittings, where MFR is raised to 0.5–1.5 for easier cavity filling while mechanics stay essentially those of the pipe compound (25 MPa, 500%). | 24 | 25 | 500 | 65 Shore D |
As built (as printed) | Choose when biofilm growth on the pipe wall must be suppressed: an inorganic biocide masterbatch in the inner layer leaves strength unchanged at 25 MPa, with 70 °C maximum service. | 24 | 25 | 550 | 66 Shore D |
Random copolymer, crystallinity/temperature modified | Pick the β-nucleated version when higher long-term hydrostatic strength (MRS 11.2) is needed to run hotter or higher-pressure water at the same wall, or to thin the wall; rated to 80 °C. | 28 | 500 | ||
PP-R/GF ≈20% | Specify the ~20% short-glass-fibre compound as the middle layer of three-layer stabilized pipe to cut thermal expansion and creep and raise modulus to 3.2 GPa; not for potable-water contact layers. | 45 | 5 |
Supply forms, finishes and certifications
Ways PP-R is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
FOOD | Potable-water / food-contact certified PP-R | Certification |
UV | UV-stabilized (carbon-black / HALS) PP-R for exposed or solar lines | Grade option |
NATDefault | Unfilled / Natural | Standard supply |
What is PP-R?
A random-copolymer PP with ethylene units statistically distributed in the chain, giving better clarity, low-temperature impact resistance and long-term hoop-stress performance than homopolymer; the standard resin for hot/cold water piping systems. PP-R has a density of 0.91 g/cm³ (0.0327 lb/in³), lighter than 81% of polymer grades. Its glass-transition temperature is -12°C (10 °F). PP-R has a yield strength of 25 MPa (3.63 ksi) and a tensile strength of 26 MPa (3.77 ksi) — weaker than 74% of polymer grades. Elongation at break is 600% and the elastic modulus is 0.85 GPa (0.123 Msi).
What is PP-R used for?
- Hot and cold water pipes
- Underfloor heating pipe
- Chemical process piping
- Pipe fittings
- Fusion-weldable pressure pipe systems
Advantages
- Readily welded — 95/100, better than 99% of polymer grades
- Low embodied carbon — 2 kg CO₂/kg, better than 96% of polymer grades
- Ductile — tolerates forming and impact — 600%, better than 93% of polymer grades
- Low moisture uptake — 0.02%, better than 92% of polymer grades
- Good corrosion resistance — 90/100, better than 82% of polymer grades
Limitations
- Degrades in UV without stabilisers — 20/100, worse than 88% of polymer grades
- Limited service temperature — 70°C (158 °F), worse than 77% of polymer grades
PP-R properties
Typical room-temperature values; bars are the position among polymer grades.
Physical6
PP-R has a density of 0.91 g/cm³ (0.0327 lb/in³), lighter than 81% of polymer grades. Its glass-transition temperature is -12°C (10 °F).
Mechanical15
PP-R has a yield strength of 25 MPa (3.63 ksi) and a tensile strength of 26 MPa (3.77 ksi) — weaker than 74% of polymer grades. Elongation at break is 600% and the elastic modulus is 0.85 GPa (0.123 Msi).
Thermal11
PP-R is rated for continuous service to 70°C (158 °F). It conducts heat at 0.24 W/m·K (0.139 BTU/hr·ft·°F), better than 67% of polymer grades. Thermal expansion is 150 µm/m·K (83.3 µin/in·°F).
Electrical7
PP-R 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 (90/100), better than 82% of polymer grades. UV resistance is poor.
Sustainability4
Producing a kilogram of PP-R takes about 78 MJ of energy and emits 2 kg of CO₂ — less than 88% of polymer grades. Typical recycled content is 0%.
Manufacturability8
PP-R's machinability is good (62/100, better than 60% of polymer grades); weldability excellent (95/100); formability very good (70/100).
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. PP-R is highlighted; hover a dot for its name, or open the interactive family chart.
Working with PP-R
Is PP-R easy to machine?
Turns, mills and drills with sharp, high-rake tooling at high speed and low feed with air cooling, which prevents melting, smearing and stress cracking. Machinability rates around 62.
Can PP-R be welded?
Socket fusion, butt fusion and electrofusion all work very well with a 260 °C heating tool, giving joints close to parent-material strength; the material cannot be solvent cemented, and adhesives are ineffective.
Can PP-R be formed, bent or molded?
Extruded into pipe at 195–230 °C and injection moulded into fittings at 210–240 °C melt with 20–60 °C tools. Shrinkage is high at 1.2–2.2 %, so cooling and hold pressure must be matched to wall thickness.
PP-R 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 |
|---|---|---|
| ethylenerandomly distributed; sets low-temperature toughness and melt point | 1.5 – 8 | 4 |
| antioxidant / heat & process stabilizer hindered phenol + phosphite system | 0.05 – 0.5 | 0.2 |
| pigment / nucleating agentgreen/grey masterbatch; PP-RCT uses beta nucleating agent | 0 – 2 | 0.5 |
| propylenebackbone monomer unit | ≥ 92 (balance) |
What surface finishes work on PP-R?
Surface energy is low (about 30 mN/m), so corona or flame treatment is required before printing or painting. It cannot be plated; parts are normally coloured with masterbatch and used as moulded.
How much does PP-R cost?
PP-R is a budget-cost polymer ($), cheaper than about 90% 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.
PP-R — frequently asked
What is PP-R used for?
PP-R is typically used for hot and cold water pipes, underfloor heating pipe, chemical process piping, pipe fittings and fusion-weldable pressure pipe systems. In short: standard fusion-welded pipe resin; 70 °C hot-water service; tougher than PP-H.
What is the yield strength of PP-R?
PP-R has a typical yield strength of 25 MPa (3.63 ksi) and a tensile strength of 26 MPa (3.77 ksi) — weaker than 74% of polymer grades. Strength varies by condition: see the 6 listed tempers.
Is PP-R easy to machine?
Reasonably — machinability is rated good (62/100, better than 60% of polymer grades). Turns, mills and drills with sharp, high-rake tooling at high speed and low feed with air cooling, which prevents melting, smearing and stress cracking. Machinability rates around 62.
Can PP-R be welded?
Yes — weldability is rated excellent (95/100). Socket fusion, butt fusion and electrofusion all work very well with a 260 °C heating tool, giving joints close to parent-material strength; the material cannot be solvent cemented, and adhesives are ineffective.
What surface finishes work on PP-R?
Surface energy is low (about 30 mN/m), so corona or flame treatment is required before printing or painting. It cannot be plated; parts are normally coloured with masterbatch and used as moulded.
Can PP-R be formed, bent or molded?
Extruded into pipe at 195–230 °C and injection moulded into fittings at 210–240 °C melt with 20–60 °C tools. Shrinkage is high at 1.2–2.2 %, so cooling and hold pressure must be matched to wall thickness.
What is the maximum service temperature of PP-R?
PP-R is rated for continuous use to about 70°C (158 °F), and briefly to 95°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does PP-R cost?
PP-R is a budget-cost polymer ($), cheaper than about 90% 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
- DIN 8077 / DIN 8078 Polypropylene (PP) pipes — dimensions and general quality requirements — DIN (2018)
- ASTM F2389 Standard Specification for Pressure-rated Polypropylene (PP) Piping Systems — ASTM International (2021)
- ISO 1873-1 Plastics — Polypropylene (PP) moulding and extrusion materials — ISO (2016)
- ISO 15874 Plastics piping systems for hot and cold water installations — Polypropylene (PP) — ISO (2013)
- PP-R / PP-RCT pipe resin technical datasheets — Borealis / LyondellBasell / (2023)
- CAMPUS polypropylene random copolymer datasets — CWFG / CAMPUS consortium (2023)
- Engineered Materials Handbook Vol.2: Engineering Plastics — ASM International (1988)
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.