PBT Polyplastics 3216
PBT Polyplastics 3216
PBT Polyplastics 3216 is a 15 % glass‑fiber‑reinforced engineering plastic with UL94 V‑0 flame retardancy. Widely applied for its favorable strength, rigidity, heat resistance, electrical performance and flame‑retardant property.
Main Applications
Electrical & Electronics (core application): connectors, switch components, sockets, coil bobbins, capacitor housings, relays, no‑fuse breakers, electromagnetic switches, flyback transformers, home‑appliance handles, housings.
Automotive industry: door handles, bumpers, distributor covers, fenders, wire harness sheaths, wheel‑cover panels, automotive electronic parts.
Household appliances: food‑processing blades, vacuum‑cleaner components, electric fans, hair‑dryer housings, coffee‑maker parts.
Industrial parts: OA fans, keyboards, fishing‑reel components, lamp housings, instrument‑meter parts requiring wear resistance, dimensional accuracy and flame retardancy.
Physical‑Mechanical‑Thermal‑Electrical Properties
| Property Category | Property Item | Test Standard / Condition | Test Data / Range | Unit |
|---|---|---|---|---|
| Physical Properties | Density | ASTM D792 | 1.54 | g/cm³ |
| Glass‑fiber content | — | 15 | % | |
| Water absorption | — | Low (value not specified) | — | |
| Mechanical Properties | Tensile strength | ASTM D638 | 112 | MPa |
| Elongation at break | ASTM D638 | 3.5 | % | |
| Flexural strength | ASTM D790 | 166 | MPa | |
| Flexural modulus | ASTM D790 | 6080 | MPa | |
| Izod notched impact | ASTM D256 | 58 | J/m | |
| Izod un‑notched impact | ASTM D256 | 440 | J/m | |
| Thermal Properties | HDT @1.82 MPa | ASTM D648 | 208 | ℃ |
| Melting point | DSC (typical PBT) | ~225 | ℃ | |
| Linear thermal expansion coefficient | — | 2‑7×10⁻⁵ | /℃ | |
| UL94 rating | UL94 | V‑0 | class | |
| Electrical Properties | Volume resistivity | ASTM D257 | 2×10¹⁶ | Ω·cm |
| Dielectric strength (short‑term,3 mm) | ASTM D149 | 20 | kV/mm | |
| Arc resistance | — | 70 | s | |
| Surface resistivity | — | 3×10¹⁶ | Ω | |
| CTI | — | 250 | V |
Injection‑Molding Parameters
| Process Stage | Parameter Item | Reference Range / Recommendation | Unit / Remarks |
|---|---|---|---|
| Pre‑treatment | Drying temperature | 120‑150 | ℃ |
| Drying time | 6‑8 h@120 ℃ or 2‑4 h@150 ℃(bed thickness＜30 mm) | h | |
| Target moisture content | ＜0.03 % (air‑dried) / ＜0.02 % critical | % | |
| Drying equipment | Desiccant dryer recommended (150 ℃, 2.5 h) | — | |
| Injection Molding | Rear barrel temperature | 220‑240 (reference setting) | ℃ |
| Middle barrel temperature | 230‑250 (reference setting) | ℃ | |
| Front barrel temperature | 240‑260 (reference setting) | ℃ | |
| Nozzle temperature | Slightly lower than or equal to front zone | ℃ | |
| Melt temperature range | 225‑275; practical production:245‑260 | ℃ | |
| Recommended melt temperature | 250 | ℃ | |
| Mold temperature | 40‑100; commonly 70‑90 ℃; FR‑GF grade 65 ℃ / unreinforced reference 40‑60 ℃ | ℃ | |
| Injection pressure | Medium; max 1500 bar / 50‑100 MPa | bar / MPa | |
| Injection speed | As fast as possible (PBT solidifies rapidly) | — | |
| Back pressure | 10‑15 % of injection pressure | MPa | |
| Screw speed | 25‑60; max ≤80 | rpm | |
| Mold | Runner type | Round runner recommended (D = part thickness + 1.5 mm) | — |
| Gate type | Various types available; hot‑runner applicable (prevent leakage & degradation) | — | |
| Gate dimension | 0.8‑1.0 × t (t = part thickness); sub‑gate min 0.75 mm | mm | |
| Mold cooling | Well‑designed cooling channels (Φ12 mm recommended), uniform & fast heat dissipation | — | |
| Mold material | Chrome‑plated surface recommended for anti‑corrosion when molding FR‑PBT | — | |
| Post‑processing | Annealing (if required) | Reduce residual stress, improve dimensional stability | ℃ |
| Annealing time | Adjust according to wall thickness | h | |
| Regrind material | Reuse ratio | 20‑65 % (clean & non‑degraded) | % |
Note: All data above is for reference only.
