POM Polyplastics DURACON M90S
POM Polyplastics DURACON® M90S (Japan Polyplastics)
POM Polyplastics M90S is a widely‑used standard‑grade, injection‑molding copolymer‑polyoxymethylene engineering plastic. It is especially suitable for applications requiring good wear resistance, high rigidity, stable dimensional performance and chemical resistance.
Main Applications
Automotive industry: fuel‑pump components, fuel‑tank caps, seat‑belt mechanical parts, exterior rear‑view mirrors, door rear‑view mirrors, engine‑compartment components and automotive interior articles. Electrical & electronic: OA equipment such as printers, copiers, keyboards and CD‑ROM drives; AV devices such as DVD / Blu‑ray players; gears, bearings and structural parts for household appliances including washing‑machines, refrigerators and electric shavers. Precision‑machinery parts: ideal for manufacturing various mechanical structural components with high‑precision, high‑wear‑resistance and low‑friction requirements, such as gears, bearings, cams, screws and pipeline valves (pump housings). Consumer & industrial goods: residential‑related components such as window‑frame and shutter parts; sanitary‑ware equipment including water taps, window frames and wash basins; toys, game‑console parts and sports‑equipment components.
Physical‑Mechanical‑Thermal‑Electrical‑Tribological Properties
| Property Category | Item | Test Standard | Value | Unit |
|---|---|---|---|---|
| Physical Properties | Density | ISO 1183 / ASTM D‑792 | 1.41 | g/cm³ |
| Water absorption (23℃, 24h) | ISO 62 | 0.6 | % | |
| MFR (190℃/2.16 kg) | ISO 1133 | 9.0 | g/10 min | |
| MVR (190℃/2.16 kg) | ISO 1133 | 8.0 | cm³/10 min | |
| Mechanical Properties | Tensile strength | ISO 527‑1,2 / ASTM D‑638 | 60‑62 | MPa |
| Elongation at break | ISO 527‑1,2 / ASTM D‑638 | 35‑60 | % | |
| Tensile modulus | ISO 527‑1,2 | 2700 | MPa | |
| Flexural strength | ISO 178 / ASTM D‑790 | 87‑96 | MPa | |
| Flexural modulus | ISO 178 / ASTM D‑790 | 2500‑2580 | MPa | |
| Charpy notched impact strength (23℃) | ISO 179/1eA | 6.0 | kJ/m² | |
| Izod notched impact strength (23℃) | ASTM D‑256 | 53‑63 | J/m | |
| Izod un‑notched impact strength (23℃) | ASTM D‑256 | 760 | J/m | |
| Rockwell hardness (M scale) | ISO 2039‑2 | 80 | — | |
| Thermal Properties | Heat deflection temperature (1.8 MPa) | ISO 75‑1,2 | 95.0 | °C |
| Heat deflection temperature (1.82 MPa) | ASTM D‑648 | 110 | °C | |
| Coefficient of linear thermal expansion (flow / cross‑flow, 23‑55°C) | Enterprise Standard / ASTM D‑696 | 10‑12 (1.0‑1.2E‑4) | ×10⁻⁵/°C or cm/cm/°C | |
| Electrical Properties | Volume resistivity | IEC 60093 / ASTM D‑257 | 1 × 10¹⁴ | Ω·cm |
| Surface resistivity | IEC 60093 / ASTM D‑257 | 1 × 10¹⁶ | Ω | |
| Dielectric strength (2 mm / 3 mm) | IEC 60243‑1 / ASTM D‑149 | 19‑24 | kV/mm or MV/m | |
| Flammability | UL94 rating | UL 94 | HB | — |
| Friction & Wear | Dynamic friction coefficient (against carbon steel) | JIS K7218 | 0.23 (0.98 MPa) | — |
| Wear loss (against carbon steel) | JIS K7218 | 0.20 | ×10⁻³ mm³/(N·km) | |
| Molding shrinkage (flow / cross‑flow direction) | ISO 294‑4 | 2.0 | % |
Injection‑Molding Parameters
| Process Stage | Parameter | Recommended Range | Unit | Remarks |
|---|---|---|---|---|
| Pre‑drying | Drying temperature | 80‑90 | °C | Although POM exhibits low moisture absorption, drying is recommended to improve dimensional stability, surface appearance and prevent surface haze. |
| Drying time | 3.0‑4.0 | hr | ||
| Residual moisture content | < 0.1 | % | ||
| Barrel temperature | Rear‑zone temperature | 180‑200 | °C | POM has a narrow processing‑window. Temperatures above 220 °C are strictly prohibited; otherwise thermal‑decomposition will generate irritating formaldehyde gas. |
| Middle‑zone temperature | 180‑195 | °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 | 60.0‑80.0 | °C | Higher mold‑temperature promotes crystallization integrity, improves dimensional stability, surface gloss and reduces sink‑marks. For precision‑parts, mold‑temperature can be controlled within 80‑100 °C. | |
| Injection parameters | Injection pressure | 49.0‑98.0 | MPa | Higher value for thin‑wall parts, lower value for thick‑wall parts. |
| Hold‑up pressure | 50.0‑150 | MPa | Relatively high hold‑up pressure (comparable to injection pressure) is required to reduce pressure drop and prevent part shrinkage. | |
| Back pressure | 0.5‑3.0 | MPa | Maintain low back‑pressure. | |
| Injection speed | Medium‑to‑high | — | The recommended processing strategy: medium pressure, medium speed, moderate‑low melt‑temperature and relatively high mold‑temperature. | |
| Screw speed | 100‑150 (adjust according to actual conditions) | rpm | Avoid excessive screw speed; keep cushion residual minimal to prevent material degradation caused by excessive shear heat. | |
| Post‑treatment | — | — | — | Generally unnecessary. 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.
