PC/PBT FR (Flame-retardant, UL 94 V-0)
Flame-retardant grade
Select for enclosures and E&E parts requiring V-0 at 1.5 mm; some loss of ductility and heat resistance.
Values for the FR condition
Other PC/PBT grades and fills
PC/PBT is listed in 7 conditions; see the grade overview at PC/PBT.
Compare all 7 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Impact-modified / high-impact grade | Pick when ductile failure is required down to -30/-40 °C, e.g. bumper systems and rocker panels. | 46 | 47 | 150 | 72 Shore D |
Post-consumer-recycled content grade | Use when 20–50 % PCR content is required by an OEM sustainability spec; slightly lower and more variable impact. | 49 | 50 | 80 | 75 Shore D |
Heat-stabilized grade | Antioxidant/heat-stabilizer package for prolonged service near 110–120 °C (e.g. paint-bake or lamp-adjacent parts). | 54 | 55 | 100 | 76 Shore D |
Mineral / talc filled | Choose for isotropic shrinkage and low CTE on large painted exterior panels without fiber read-through. | 56 | 57 | 25 | 80 Shore D |
FRThis page Flame-retardant, UL 94 V-0 | Select for enclosures and E&E parts requiring V-0 at 1.5 mm; some loss of ductility and heat resistance. | 56 | 57 | 55 | 78 Shore D |
15 % glass-fiber reinforced | Mid stiffness/low warpage compromise for painted structural trim and brackets. | — | 85 | 6 | — |
30 % glass-fiber reinforced | Highest stiffness and heat resistance of the family; use for load-bearing housings and under-hood brackets. | — | 115 | 3.5 | — |
What is PC/PBT FR?
PC/PBT FR is PC/PBT in the FR grade — select for enclosures and E&E parts requiring V-0 at 1.5 mm; some loss of ductility and heat resistance. PC/PBT FR has a yield strength of 56 MPa (8.12 ksi) and a tensile strength of 57 MPa (8.27 ksi) — stronger than 63% of polymer grades. Elongation at break is 55% and the elastic modulus is 2.4 GPa (0.348 Msi). PC/PBT FR has a density of 1.33 g/cm³ (0.048 lb/in³), heavier than 73% of polymer grades. Its glass-transition temperature is 130°C (266 °F).
Advantages
- Good UV / weathering resistance — 55/100, better than 77% of polymer grades
PC/PBT FR properties
Typical room-temperature values for PC/PBT FR; 29 are specific to this condition. Other listed values are PC/PBT reference data and may not represent this condition. Bars are the position among polymer grades.
Physical5
PC/PBT FR has a density of 1.33 g/cm³ (0.048 lb/in³), heavier than 73% of polymer grades. Its glass-transition temperature is 130°C (266 °F).
Mechanical11
PC/PBT FR has a yield strength of 56 MPa (8.12 ksi) and a tensile strength of 57 MPa (8.27 ksi) — stronger than 63% of polymer grades. Elongation at break is 55% and the elastic modulus is 2.4 GPa (0.348 Msi).
Thermal11
PC/PBT FR is rated for continuous service to 100°C (212 °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 80 µm/m·K (44.4 µin/in·°F).
Electrical7
PC/PBT FR is an electrical insulator with a dielectric strength of 26 kV/mm (660.4 V/mil) and a resistivity of 1×10¹³ Ω·m.
Chemical & Environmental3
Corrosion resistance is very good (80/100), worse than 52% of polymer grades. UV resistance is good.
Sustainability4
Producing a kilogram of PC/PBT FR takes about 95 MJ of energy and emits 5.5 kg of CO₂ — less than 70% of polymer grades. Typical recycled content is 10%.
Manufacturability7
PC/PBT FR's machinability is good (60/100, better than 51% of polymer grades); weldability good (65/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with PC/PBT FR
Is PC/PBT easy to machine?
Machines like tough PC: sharp positive-rake carbide tools, high speed / moderate feed, air or mist cooling; avoid stress-inducing dry drilling and anneal (~110 °C) before solvent contact.
Can PC/PBT be welded?
Joins well by ultrasonic, laser, hot-plate and vibration welding; adhesive bonding with polyurethane/epoxy after abrasion or flame/plasma treatment — avoid solvent cements that stress-crack the PC phase.
Can PC/PBT be formed, bent or molded?
Injection mold at 245–275 °C melt / 50–90 °C tool with pellets dried to <0.02 % moisture (2–4 h at 100–120 °C) to prevent hydrolytic splay and loss of impact; shrinkage 0.5–1.0 % unfilled.
What surface finishes work on PC/PBT?
Excellent for painting — accepts 1K/2K automotive basecoat-clearcoat with adhesion promoter; can be laser-marked, hot-stamped, in-mold decorated or vacuum metallized, but is opaque and not suitable for optical polishing.
PC/PBT 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 |
|---|---|---|
| polycarbonate (PC)bisphenol-A polycarbonate matrix phase | 45 – 75 | 60 |
| poly(butylene terephthalate) (PBT)semi-crystalline phase, provides chemical/weather resistance | 20 – 50 | 32 |
| impact modifier (MBS/core-shell acrylic low-temperature toughness | 3 – 12 | 6 |
| compatibilizer / transesterification catphosphite/epoxy stabilizers, antioxidants, mold release | 0.3 – 2 | 1 |
PC/PBT FR — frequently asked
What is PC/PBT FR used for?
PC/PBT FR is typically used for automotive body panels, bumper components, electrical enclosures and chemical-resistant housings. In short: paintable exterior PC blend; better chemical resistance than PC; tough at low temperature.
What is the yield strength of PC/PBT FR?
PC/PBT FR has a typical yield strength of 56 MPa (8.12 ksi) and a tensile strength of 57 MPa (8.27 ksi) — stronger than 63% of polymer grades. Strength varies by condition: see the 7 listed tempers.
Is PC/PBT FR easy to machine?
Reasonably — machinability is rated good (60/100, better than 51% of polymer grades). Machines like tough PC: sharp positive-rake carbide tools, high speed / moderate feed, air or mist cooling; avoid stress-inducing dry drilling and anneal (~110 °C) before solvent contact.
Can PC/PBT FR be welded?
Yes — weldability is rated good (65/100). Joins well by ultrasonic, laser, hot-plate and vibration welding; adhesive bonding with polyurethane/epoxy after abrasion or flame/plasma treatment — avoid solvent cements that stress-crack the PC phase.
What surface finishes work on PC/PBT FR?
Excellent for painting — accepts 1K/2K automotive basecoat-clearcoat with adhesion promoter; can be laser-marked, hot-stamped, in-mold decorated or vacuum metallized, but is opaque and not suitable for optical polishing.
Can PC/PBT FR be formed, bent or molded?
Injection mold at 245–275 °C melt / 50–90 °C tool with pellets dried to <0.02 % moisture (2–4 h at 100–120 °C) to prevent hydrolytic splay and loss of impact; shrinkage 0.5–1.0 % unfilled.
What is the maximum service temperature of PC/PBT FR?
PC/PBT FR is rated for continuous use to about 100°C (212 °F), and briefly to 130°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- ASTM D5927 — Standard Specification for Thermoplastic Polyester (TPES) Injection Molding and Extrusion Materials — ASTM International (2018)
- ISO 7391 — Polycarbonate (PC) moulding and extrusion materials — ISO (2006)
- Xenoy PC/PBT resin product datasheets and processing guide — SABIC Specialties (2023)
- Makroblend PC+PBT grade datasheets — Covestro (2023)
- CAMPUS plastics database — PC+PBT blends (ISO 10350 datasets) — CWFG / CAMPUS consortium (2024)
- Engineered Materials Handbook Vol. 2: Engineering Plastics — ASM 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.