FabDigit

PP · grade

PP Standard

Properties of the Standard condition, compared with the other PP grades.

Generic commodity PP when the datasheet does not distinguish homo- from copolymer; safe average design values.

What is PP Standard?

PP Standard is PP in the Standard grade — generic commodity PP when the datasheet does not distinguish homo- from copolymer; safe average design values. PP Standard has a yield strength of 30 MPa (4.35 ksi) and a tensile strength of 32 MPa (4.64 ksi) — weaker than 74% of polymer grades. Elongation at break is 200% and the elastic modulus is 1.5 GPa (0.218 Msi). PP Standard has a density of 0.91 g/cm³ (0.0327 lb/in³), lighter than 80% of polymer grades. Its glass-transition temperature is -10°C (14 °F). Homopolymer is the default condition FabDigit quotes; Standard is available on request or by drawing note.

Advantages

  • Readily welded — 92/100, better than 97% of polymer grades
  • Low embodied carbon — 2 kg CO₂/kg, better than 96% of polymer grades
  • Low moisture uptake — 0.02%, better than 92% of polymer grades
  • Good corrosion resistance — 92/100, better than 91% of polymer grades
  • Tough — resists crack growth — 3.5 MPa·√m (3.19 ksi·√in), better than 80% of polymer grades

Limitations

  • Degrades in UV without stabilisers — 20/100, worse than 88% of polymer grades

PP Standard properties

Typical room-temperature values for PP Standard — 9 properties are specific to this condition; the rest are grade-level values shared by every PP grade. Each bar shows where the value sits among the polymer grades in FabDigit's library — further right is higher.

Physical6

PP Standard has a density of 0.91 g/cm³ (0.0327 lb/in³), lighter than 80% of polymer grades. Its glass-transition temperature is -10°C (14 °F).

Density0.91 g/cm³0.03 lb/in³
Melting Temperature (Tm)165°C329 °F
Glass Transition (Tg)-10°C14 °F
Water Absorption (24 h)0.02%
Water Absorption (Saturation)0.1%
Refractive Index1.49

Mechanical16

PP Standard has a yield strength of 30 MPa (4.35 ksi) and a tensile strength of 32 MPa (4.64 ksi) — weaker than 74% of polymer grades. Elongation at break is 200% and the elastic modulus is 1.5 GPa (0.218 Msi).

Elastic (Young's) Modulus1.5 GPa0.22 Msi
Shear Modulus0.55 GPa0.08 Msi
Bulk Modulus3 GPa0.45 Msi
Poisson's Ratio0.42
Tensile Strength (Ultimate)32 MPa4.6 ksi
Yield Strength (0.2% offset)30 MPa4.4 ksi
Elongation at Break200%
Compressive Strength42 MPa6.1 ksi
Compressive Modulus1.4 GPa0.2 Msi
Flexural Strength45 MPa6.5 ksi
Flexural Modulus1.4 GPa0.2 Msi
Shear Strength25 MPa3.6 ksi
Fracture Toughness (K_IC)3.5 MPa·√m3.2 ksi·√in
Izod Impact, Notched45 J/m0.84 ft·lbf/in
Hardness, Shore D72 Shore D
Hardness, Rockwell R95 HRR

Thermal11

PP Standard is rated for continuous service to 95°C (203 °F). It conducts heat at 0.22 W/m·K (0.127 BTU/hr·ft·°F), better than 60% of polymer grades. Thermal expansion is 110 µm/m·K (61.1 µin/in·°F).

Thermal Conductivity0.22 W/m·K0.13 BTU/hr·ft·°F
Specific Heat Capacity1,900 J/kg·K0.45 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)110 µm/m·K61.1 µin/in·°F
Max Service Temperature (continuous)95°C203 °F
Min Service Temperature-10°C14 °F
Heat Deflection Temp. @ 0.45 MPa105°C221 °F
Heat Deflection Temp. @ 1.8 MPa55°C131 °F
Vicat Softening Point (B50)90°C194 °F
Flammability (UL 94)HB (unmodified; burns readily with dripping)
Limiting Oxygen Index18%
Max Service Temperature (short-term)130°C266 °F

Electrical7

PP Standard is an electrical insulator with a dielectric strength of 25 kV/mm (635 V/mil) and a resistivity of 1×10¹⁴ Ω·m.

Electrical Resistivity1×10¹⁴ Ω·m3.94×10²¹ µΩ·in
Dielectric Strength25 kV/mm635 V/mil
Dielectric Constant (1 MHz)2.25
Dissipation Factor (1 MHz)3×10⁻⁴
Volume Resistivity1×10¹⁶ Ω·cm
Surface Resistivity1×10¹⁵ Ω
Comparative Tracking Index (CTI)600 V

Chemical & Environmental3

Corrosion resistance is excellent (92/100), better than 91% of polymer grades. UV resistance is poor.

Corrosion ResistanceExcellent92/100
UV / Weathering ResistancePoor20/100
Chemical Resistance SummaryExcellent against water, brines, acids, alkalis, alcohols and most aqueous salts up to ~80–100 °C; good against polar solvents. Attacked/swollen by chlorinated and aromatic hydrocarbons, and by strong oxidizers (fuming nitric/sulfuric acid, halogens); susceptible to thermo-oxidative and UV degradation without stabilizers, and to environmental stress cracking in hot surfactants under load.

Sustainability4

Producing a kilogram of PP Standard takes about 78 MJ of energy and emits 2 kg of CO₂ — less than 88% of polymer grades. Typical recycled content is 5%.

Embodied Energy (primary production)78 MJ/kg33,534 BTU/lb
Embodied Carbon (primary production)2 kg CO₂/kg
Embodied Water100 L/kg12 gal/lb
Typical Recycled Content5%

Manufacturability8

PP Standard's machinability is good (60/100, better than 51% of polymer grades); weldability excellent (92/100); formability very good (80/100).

MachinabilityGood60/100
WeldabilityExcellent92/100
Formability (cold)Very good80/100
PolishabilityFair40/100
Mold Shrinkage1.6%
Melt Flow Rate12 g/10 min
Processing Melt Temperature (typ.)230°C446 °F
Mold Temperature (typ.)40°C104 °F

Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.

Other PP grades and fills

PP is also supplied in 13 other conditions. The full side-by-side table is on the PP overview.

Working with PP Standard

Is PP easy to machine?

Machines easily but is soft and gummy — use sharp, high-rake tools, high speed with low feed pressure, air blast cooling, and generous support to control springback; annealed stock reduces post-machining distortion.

Can PP be welded?

Excellent hot-gas, extrusion, butt-fusion, socket-fusion, ultrasonic, vibration and spin welding with PP filler; no solvent cementing exists — adhesive bonding needs flame/corona/plasma pretreatment or polyolefin primer.

Can PP be formed, bent or molded?

Injection molds at 200–260 °C melt / 20–60 °C tool; shrinkage is high (1.2–2.2%) and crystallization-driven, so allow for post-mold shrink and warp, use uniform walls, and thermoform sheet in the narrow 150–165 °C window.

What surface finishes work on PP?

Cannot be electroplated or anodized; paint and print only after flame/corona/plasma treatment with adhesion promoter, otherwise use in-mold texture, mass coloring or laser marking.

PP 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.

ElementSpec limit (wt %)Nominal
ethylene comonomer2–7% in random copolymer (PP-R), 5–15% EPR phase in impact copolymer0 – 120
antioxidant / process stabilizerhindered phenol + phosphite0.05 – 0.50.2
nucleating agent / acid scavengerCa-stearate, sorbitol clarifier0 – 0.30.1
glass fiberGF10–GF40 variants, MAH-PP coupled0 – 400
talc / CaCO3 fillermineral-filled variants0 – 400
propylene repeat unit (C3H6)isotactic polypropylene backbone; copolymer grades contain ethylene comonomer≥ 92 (balance)

PP Standard — frequently asked

What is PP Standard used for?

PP Standard is typically used for chemical storage tanks and liners, food packaging containers and closures, living-hinge lids and boxes, pipe and fittings for corrosive fluids, automotive interior trim and battery cases and laboratory labware and trays. In short: rigid; standard plastic.

What is the yield strength of PP Standard?

PP Standard has a typical yield strength of 30 MPa (4.35 ksi) and a tensile strength of 32 MPa (4.64 ksi) — weaker than 74% of polymer grades. Strength varies by condition: see the 14 listed tempers.

Is PP Standard easy to machine?

Reasonably — machinability is rated good (60/100, better than 51% of polymer grades). Machines easily but is soft and gummy — use sharp, high-rake tools, high speed with low feed pressure, air blast cooling, and generous support to control springback; annealed stock reduces post-machining distortion.

Can PP Standard be welded?

Yes — weldability is rated excellent (92/100). Excellent hot-gas, extrusion, butt-fusion, socket-fusion, ultrasonic, vibration and spin welding with PP filler; no solvent cementing exists — adhesive bonding needs flame/corona/plasma pretreatment or polyolefin primer.

What surface finishes work on PP Standard?

Cannot be electroplated or anodized; paint and print only after flame/corona/plasma treatment with adhesion promoter, otherwise use in-mold texture, mass coloring or laser marking.

Can PP Standard be formed, bent or molded?

Injection molds at 200–260 °C melt / 20–60 °C tool; shrinkage is high (1.2–2.2%) and crystallization-driven, so allow for post-mold shrink and warp, use uniform walls, and thermoform sheet in the narrow 150–165 °C window.

What is the maximum service temperature of PP Standard?

PP Standard is rated for continuous use to about 95°C (203 °F), and briefly to 130°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

Can FabDigit make parts in PP Standard?

Yes — PP Standard is available for CNC machining, sheet metal, injection molding and 3D printing with instant online pricing. Upload a STEP file to get a price and a DFM check.

Sources

  1. ASTM D4101 – Standard Classification for Polypropylene Injection and Extrusion MaterialsASTM International (2023)
  2. ISO 19069-1/-2 – Plastics: Polypropylene (PP) moulding and extrusion materialsISO (2019)
  3. GB/T 2546.1 / GB/T 12670 (PP)SAC (2018)
  4. Moplen / Pro-fax / Hostacom PP grade datasheetsLyondellBasell (2023)
  5. Borealis / Borouge PP homopolymer and copolymer datasheetsBorealis (2023)
  6. CAMPUS plastics database – PP entries (ISO 10350 property set)CWFG / CAMPUS consortium (2024)
  7. Engineered Materials Handbook Vol.2: Engineering PlasticsASM International (1988)

Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.