PCT GF-MIN
Reinforced grade
also Thermx
GF-MIN = glass/mineral filled, low-warp
Use where flatness and isotropic shrinkage matter more than peak strength (large flat covers, housings).
Values for the GF-MIN condition
Other PCT grades and fills
PCT is listed in 8 conditions; see the grade overview at PCT.
Compare all 8 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
15 % glass-fiber reinforced | Lower-warp reinforced grade when moderate stiffness and better surface appearance are needed. | — | 95 | 3.5 | — |
GF-MINThis page Glass/mineral filled, low-warp | Use where flatness and isotropic shrinkage matter more than peak strength (large flat covers, housings). | 95 | 95 | 2 | 92 HRM |
Impact-modified PCT | Pick for snap-fit or press-fit parts needing higher notched toughness at some loss of stiffness and HDT. | 105 | 105 | 3.5 | 88 HRM |
High-reflectance white LED-housing grade | TiO2-loaded, glass-reinforced white compound for LED reflector cups needing low yellowing after reflow and UV exposure. | 105 | 105 | 1.6 | 95 HRM |
30 % glass, flame-retardant UL 94 V-0 | Choose when the electrical connector or bobbin must carry a UL 94 V-0 rating at 0.4–0.8 mm wall. | — | 115 | 1.8 | — |
Heat-stabilized / hydrolysis-resistant grade | Long-term 150 °C air-oven ageing or humid under-hood service; adds thermal and hydrolysis stabilizers to a GF30 base. | 128 | 128 | 2.2 | 94 HRM |
30 % glass-fiber reinforced | The mainstream commercial PCT grade for SMT connectors and coil bobbins that must survive lead-free reflow. | — | 130 | 2.2 | 92 HRM |
40 % glass-fiber reinforced | Maximum stiffness/strength and lowest CTE for thin-wall high-temperature structural connector bodies. | — | 150 | 1.8 | — |
What is PCT GF-MIN?
PCT GF-MIN is PCT in the GF-MIN grade — use where flatness and isotropic shrinkage matter more than peak strength (large flat covers, housings). PCT GF-MIN has a yield strength of 95 MPa (13.8 ksi) and a tensile strength of 95 MPa (13.8 ksi) — stronger than 93% of polymer grades. Elongation at break is 2% and the elastic modulus is 9 GPa (1.31 Msi). PCT GF-MIN has a density of 1.62 g/cm³ (0.0585 lb/in³), heavier than 94% of polymer grades. Its glass-transition temperature is 90°C (194 °F).
Advantages
- High strength — 95 MPa (13.8 ksi), better than 93% of polymer grades
- Stiff — 9 GPa (1.31 Msi), better than 93% of polymer grades
- Conducts heat well — 0.3 W/m·K (0.173 BTU/hr·ft·°F), better than 83% of polymer grades
- High service temperature — 150°C (302 °F), better than 79% of polymer grades
- Low moisture uptake — 0.09%, better than 79% of polymer grades
Limitations
- Limited ductility — 2%, worse than 95% of polymer grades
- Limited formability — 5/100, worse than 95% of polymer grades
- Heavy — 1.62 g/cm³ (0.0585 lb/in³), worse than 94% of polymer grades
- Difficult to machine — 35/100, worse than 84% of polymer grades
- Needs corrosion protection — 70/100, worse than 78% of polymer grades
PCT GF-MIN properties
Typical room-temperature values for PCT GF-MIN; 25 are specific to this condition. Other listed values are PCT reference data and may not represent this condition. Bars are the position among polymer grades.
Physical6
PCT GF-MIN has a density of 1.62 g/cm³ (0.0585 lb/in³), heavier than 94% of polymer grades. Its glass-transition temperature is 90°C (194 °F).
Mechanical10
PCT GF-MIN has a yield strength of 95 MPa (13.8 ksi) and a tensile strength of 95 MPa (13.8 ksi) — stronger than 93% of polymer grades. Elongation at break is 2% and the elastic modulus is 9 GPa (1.31 Msi).
Thermal11
PCT GF-MIN is rated for continuous service to 150°C (302 °F). It conducts heat at 0.3 W/m·K (0.173 BTU/hr·ft·°F), better than 83% of polymer grades. Thermal expansion is 68 µm/m·K (37.8 µin/in·°F).
Electrical7
PCT GF-MIN is an electrical insulator with a dielectric strength of 22 kV/mm (558.8 V/mil) and a resistivity of 1×10¹⁴ Ω·m.
Chemical & Environmental3
Corrosion resistance is very good (70/100), worse than 78% of polymer grades. UV resistance is good.
Sustainability4
Producing a kilogram of PCT GF-MIN takes about 100 MJ of energy and emits 4.6 kg of CO₂ — less than 61% of polymer grades. Typical recycled content is 0%.
Manufacturability8
PCT GF-MIN's machinability is fair (35/100, worse than 84% of polymer grades); weldability poor (20/100); formability not recommended (5/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with PCT GF-MIN
Is PCT easy to machine?
Machinable with sharp carbide tooling and air cooling, but glass-filled grades are abrasive and notch-sensitive — generous radii and light finishing cuts.
Can PCT be welded?
Joined by ultrasonic, hot-plate, laser and vibration welding as well as heat staking; not solvent-bondable in practice, adhesives need surface pre-treatment.
Can PCT be formed, bent or molded?
Injection mold at 295–325 °C melt with 100–140 °C mold and dry the resin to <0.02 % moisture (4 h @ 120–140 °C) to avoid hydrolytic MW loss; hot runners and fast fill suit thin-wall connectors.
What surface finishes work on PCT?
Mold-textured or gloss finishes replicate well; laser marking and pad printing are common, and reinforced grades can be electroplated only with specialty pre-treatment.
PCT 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 |
|---|---|---|
| terephthalic acid / DMT (terephthalate udiacid component, mol % of repeat unit | 48 – 52 | 50 |
| 1,4-cyclohexanedimethanol (CHDM)glycol component; high trans-isomer content gives the high melting point | 48 – 52 | 50 |
| glass fiberchopped E-glass in reinforced grades | 0 – 45 | 30 |
| stabilizers / nucleants / pigmentsthermal, hydrolysis and UV additive package | 0.3 – 5 | 1.5 |
PCT GF-MIN — frequently asked
What is PCT GF-MIN used for?
PCT GF-MIN is typically used for SMT/lead-free reflow connectors, LED reflectors, high-heat electrical components and specialty fiber and film. In short: reflow-tolerant polyester; higher melting than PET/PBT; thin-wall connector resin.
What is the yield strength of PCT GF-MIN?
PCT GF-MIN has a typical yield strength of 95 MPa (13.8 ksi) and a tensile strength of 95 MPa (13.8 ksi) — stronger than 93% of polymer grades. Strength varies by condition: see the 8 listed tempers.
Is PCT GF-MIN easy to machine?
Not especially — machinability is rated fair (35/100, worse than 84% of polymer grades). Machinable with sharp carbide tooling and air cooling, but glass-filled grades are abrasive and notch-sensitive — generous radii and light finishing cuts.
Can PCT GF-MIN be welded?
Not readily — weldability is rated poor (20/100). Joined by ultrasonic, hot-plate, laser and vibration welding as well as heat staking; not solvent-bondable in practice, adhesives need surface pre-treatment.
What surface finishes work on PCT GF-MIN?
Mold-textured or gloss finishes replicate well; laser marking and pad printing are common, and reinforced grades can be electroplated only with specialty pre-treatment.
Can PCT GF-MIN be formed, bent or molded?
Injection mold at 295–325 °C melt with 100–140 °C mold and dry the resin to <0.02 % moisture (4 h @ 120–140 °C) to avoid hydrolytic MW loss; hot runners and fast fill suit thin-wall connectors.
What is the maximum service temperature of PCT GF-MIN?
PCT GF-MIN is rated for continuous use to about 150°C (302 °F), and briefly to 260°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- Thermx PCT high-heat polyester product data — Eastman Chemical / Celanese (2020)
- CAMPUS / Prospector thermoplastic polyester datasheets — CAMPUS Consortium / UL (2023)
- Polymer Data Handbook — poly(cyclohexylenedimethylene terephthalate) — Oxford University Press (2009)
- ISO 527 / ISO 178 / ISO 75 plastics test methods — ISO (2019)
- ASTM D638 / D790 / D648 / D256 — ASTM (2022)
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.