POM DuPont Delrin 500P
POM DuPont Delrin® 500P
POM DuPont Delrin® 500P is medium‑viscosity homopolymer‑acetal(POM‑H) injection grade. It provides high rigidity, high strength and excellent wear‑resistance, good dimensional‑stability, fair chemical‑resistance, self‑lubricity and broad service‑temperature range, widely‑used general‑purpose base grade for Delrin series。
Main Applications
Automotive: fuel‑pump assemblies, fuel‑cap, seat‑belt components, handle‑parts, power‑window parts, pipe fittings, sliders. Electrical & electronic: gears, bearings and structural parts for home‑appliance timers, keyboard, audio‑video devices. Precision‑machinery & industrial components: gears, bearings, cams, screws, levers, pulleys, sprockets, valve‑pipe parts, fasteners and engineering fittings. Consumer goods: zippers, toys, sports‑equipment, lighters; extruded sheets, strips and tubes。
Physical‑Mechanical‑Thermal‑Electrical Properties
| Property Category | Item | Test Standard | ASTM | ISO | Unit |
|---|---|---|---|---|---|
| Physical Properties | Density | ASTM D‑792 / ISO 1183 | 1.42 | 1.42 | g/cm³ |
| Water absorption (24 h immersion) | ASTM D‑570 / ISO 62 | 0.25 | 1.4(2 mm) | % | |
| Water absorption (50 %RH equilibrium) | ASTM D‑570 / ISO 62 | 0.22 | 0.30 | % | |
| MFR (190 ℃ / 2.16 kg) | ASTM D‑1238 / ISO 1133 | 9.0 | 15.0 | g/10 min | |
| Molding shrinkage (flow) | — / ISO 294‑4 | 2.2‑2.4 | 2.0 | % | |
| Molding shrinkage (transverse) | — / ISO 294‑4 | — | 1.9 | % | |
| Mechanical Properties | Tensile yield strength 23℃ | ASTM D‑638 / ISO 527‑2 | 69 | 71.0 | MPa |
| Elongation at break | ASTM D‑638 / ISO 527‑2 | 35 | 30 | % | |
| Tensile modulus | ASTM D‑638 / ISO 527‑2 | 3360 | 3100 | MPa | |
| Flexural strength | ASTM D‑790 / ISO 178 | 97 | 80.0(3.5%strain) | MPa | |
| Flexural modulus | ASTM D‑790 / ISO 178 | 3090 | 2950 | MPa | |
| Izod notched impact 23℃ | ASTM D‑256 / ISO 180/1A | 81 | 9.0 | J/m；kJ/m² | |
| Compressive strength(10 %strain) | ASTM D‑695 | 123 | — | MPa | |
| Rockwell hardness M‑scale | ASTM D‑785 / ISO 2039‑2 | 94 | 92 | — | |
| Thermal Properties | HDT (1.8 MPa) | ASTM D‑648 / ISO 75‑2/A | 136 | 95.0 | ℃ |
| HDT (0.45 MPa) | ASTM D‑648 / ISO 75‑2/B | 172 | 160 | ℃ | |
| Melting point | ASTM D‑2133 / ISO 11357‑3 | 175 | 178 | ℃ | |
| CLTE (flow direction) | ASTM D‑696 / ISO 11359‑2 | 10.4‑14.9×10⁻⁵ | 1.1E‑4 | cm/cm/℃ | |
| Electrical Properties | Volume resistivity | ASTM D‑257 / IEC 60093 | 1×10¹⁵ | 2.0×10¹⁴ | Ω·cm |
| Dielectric strength(2.3 mm) | ASTM D‑149 / IEC 60243‑1 | 19.7 | 44 | kV/mm | |
| Dielectric constant(1 MHz) | ASTM D‑150 / IEC 60250 | 3.7 | 3.80 | — | |
| Flammability | UL94 | UL 94 | HB | HB | — |
Injection‑Molding Parameters
| Process Stage | Parameter | Recommended Range | Unit | Remarks |
|---|---|---|---|---|
| Pre‑drying | Pre‑treatment | Optional, pre‑heat recommended | — | No mandatory drying; 80 ℃ pre‑heat improves dimensional‑stability. |
| Barrel temperature | Rear zone | 150‑180 | ℃ | Narrow processing window. Melt shall never exceed 220 ℃, otherwise formaldehyde decomposition occurs. |
| Middle zone | 170‑190 | ℃ | ||
| Front zone | 180‑200 | ℃ | ||
| Nozzle temperature | 170‑190 | ℃ | Slightly lower than front‑zone temperature to prevent drooling. | |
| Melt temperature | 190‑210 | ℃ | ||
| Mold temperature | 80‑100 | ℃ | Higher mold‑temperature improves crystallization, gloss and reduces sink‑marks. | |
| Injection parameters | Injection pressure | 40‑130 | MPa | Adjust by wall‑thickness. |
| Hold‑up pressure | Close to injection pressure | MPa | Adequate hold‑pressure compensates shrinkage and sink‑marks. | |
| Back pressure | 0.5‑2.0(minimum preferred) | MPa | High back‑pressure causes shear‑overheat degradation. | |
| Injection speed | Medium | — | Process strategy: medium pressure, medium speed, low melt temperature, high mold‑temperature. | |
| Screw speed | 100‑150 | rpm | Avoid excessive screw‑speed; keep small cushion to reduce shear heat. | |
| Barrel residence time | ＜20 | min | Short residence time required. | |
| Shutdown procedure | Short‑term stop | Cool barrel below 150 | ℃ | Long‑term shutdown: fully purge barrel with PE / PP. |
| Post‑treatment | Annealing(optional) | — | — | For high‑precision parts working under non‑ambient condition, relieve residual stress. |
Note: All data for reference only, subject to official TDS and COA。
