POM Polyplastics DURACON NW‑02
POM Polyplastics DURACON® NW‑02 (Japan Polyplastics)
POM Polyplastics NW‑02 is a copolymer polyacetal material compounded with special lubricant additives, a special‑grade engineering plastic with greatly enhanced self‑lubricity and wear resistance for high‑sliding and low‑friction applications.
Main Applications
Automotive: fuel‑pump components, window regulator parts, door lock systems, seat‑belt components, various bearings and bushings. Office‑equipment & precision‑machinery: transmission and sliding components for OA and AV devices such as printers, copiers (gears, cams, sliding parts) and optical disc drives. Consumer & industrial goods: zippers, pulleys, toys, gears and bearings for sports equipment, window‑frame and shutter components and other fields requiring smooth movement performance. Other fields: widely used in building materials, agricultural machinery, medical‑technical devices and other industries.
Physical‑Mechanical‑Tribological‑Thermal‑Electrical Properties
| Property Category | Item | Test Standard | Value | Unit |
|---|---|---|---|---|
| Physical Properties | Density | ASTM D‑792 | 1.36 | g/cm³ |
| Water absorption (24hr, 23℃) | ISO 62 | 0.70 | % | |
| MFR (190℃/2.16kg) | ISO 1133 | 20.0 | g/10 min | |
| Molding shrinkage (flow direction) | ISO 294‑4 | 2.0 | % | |
| Molding shrinkage (cross‑flow direction) | ISO 294‑4 | 1.8 | % | |
| Mechanical Properties | Tensile strength | ASTM D‑638 | 52 | MPa |
| Elongation at break | ASTM D‑638 | 35 | % | |
| Tensile modulus | ISO 527‑2 | 341000 | psi | |
| Flexural strength | ASTM D‑790 | 77 | MPa | |
| Flexural modulus | ASTM D‑790 | 2300 | MPa | |
| Izod notched impact strength | ASTM D‑256 | 58 | J/m | |
| Izod un‑notched impact strength | ASTM D‑256 | 880 | J/m | |
| Charpy notched impact strength (23℃) | ISO 179/1eA | 2.8 | ft·lb/in² | |
| Rockwell hardness (M scale) | ISO 2039‑2 | 70 | — | |
| Friction & Wear | Dynamic friction coefficient (against steel) | JIS K7218 | 0.17 | — |
| Dynamic friction coefficient (against POM) | JIS K7218 | 0.32 | — | |
| Wear factor (specified condition) | JIS K7218 | < 0.50‑500 | 10⁻¹⁰ in³·min/(ft·lb·hr) | |
| Thermal Properties | Heat deflection temperature (1.82 MPa) | ASTM D‑648 | 117 | °C |
| Heat deflection temperature (0.46 MPa or 264 psi) | ISO 75‑2/A | 85 (approx.185°F) | °C (°F) | |
| Coefficient of linear thermal expansion (flow/cross‑flow,23‑55°C) | Internal method | 6.7E‑5 | in/in/°F | |
| Electrical Properties | Volume resistivity | IEC 60093 | 1 × 10¹⁴ | Ω·cm |
| Surface resistivity | IEC 60093 | 3 × 10¹⁵ | Ω | |
| Dielectric strength (3 mm) | IEC 60243‑1 | 19.7 (approx.510 V/mil) | kV/mm (V/mil) | |
| Flammability | UL94 rating | UL 94 | HB | — |
Injection‑Molding Parameters
| Process Stage | Parameter | Recommended Range | Unit | Remarks |
|---|---|---|---|---|
| Pre‑drying | Drying temperature | 80‑90 | °C | Although POM has low moisture absorption, drying is recommended for better dimensional stability, surface appearance and to prevent surface haze. |
| Drying time | 3.0‑4.0 | hr | ||
| Residual moisture content | < 0.1‑0.2 | % | ||
| Barrel temperature | Rear zone temperature | 170‑190 | °C | POM has a narrow processing window. Strictly avoid temperature above 220°C, otherwise irritating formaldehyde gas will be generated by thermal decomposition. |
| Middle zone temperature | 180‑200 | °C | ||
| Front zone temperature | 185‑210 | °C | ||
| Nozzle temperature | 180‑210 | °C | Slightly lower than or close to front‑zone temperature. | |
| Melt temperature | 190‑210 | °C | ||
| Mold temperature | 60‑80 (or 140‑176°F) | °C (°F) | Higher mold temperature improves crystallization integrity, dimensional stability, surface gloss and reduces sink marks. | |
| Injection parameters | Injection pressure | 49‑98 (approx.500‑1000 kgf/cm²) | MPa | Higher value for thin‑wall parts, lower value for thick‑wall parts. |
| Hold‑up pressure | Comparable to injection pressure | MPa | Relatively high hold‑up pressure is required to reduce pressure drop and prevent part shrinkage. | |
| Back pressure | 0.5‑3.0 | MPa | Keep back pressure at low level. | |
| Injection speed | 5‑50 (approx.0.3‑3 m/min) | mm/s (m/min) | ||
| Screw speed | 100‑150 | rpm | Avoid excessive screw speed; keep cushion residual minimal to prevent material degradation caused by excessive shear heat. | |
| Post‑treatment | — | — | — | Generally not required. Conditioning or annealing treatment can be applied for high‑precision parts to release internal stress. |
| Barrel residence time | ＜20 | min | Avoid long‑term high‑temperature retention. | |
| Shutdown procedure | Short‑term stop | Cool barrel below 150 | °C | Long‑term shutdown purge barrel with PE / PP. |
Note: All data for reference only, subject to official TDS and COA.
