POM YUNTIANHUA M270
POM YUNTIANHUA M270
POM YUNTIANHUA M270 is high‑flow copolymer acetal. It features good rigidity, excellent dimensional stability, wide service temperature range, favorable wear‑resistance and chemical‑resistance, especially suitable for thin‑wall & complex‑structure molded articles.
Main Applications
Thin‑wall & complex‑structure parts: injection‑molded complex, high‑precision, thin‑wall articles and long‑flow‑path products. Electrical & electronic: gears, bearings and structural components for home appliances such as washing‑machine & juicer parts, timer assemblies, keyboard & switch components. Automotive: gears, bearings, auto parts, machine‑tool & instrument inner skeleton components. Precision mechanical & industrial parts: gears, bearings, cams, screws, levers, pulleys, sprockets, pipe valves, fasteners and engineering fittings. Consumer & others: lighters, zippers, buttons, toys, sports goods and packaging containers such as bottles.
Physical Properties
| Property Category | Item | Test Standard | Typical Data | Unit |
|---|---|---|---|---|
| Physical Properties | Density | ISO 1183 | 1.41 | g/cm³ |
| Water absorption (23℃,24h) | ISO 62 | 0.50‑0.70 | % | |
| MFR (190℃/2.16kg) | ISO 1133 | 27.0 | g/10min | |
| Mechanical Properties | Tensile yield strength (23℃) | ISO 527‑2 | 62‑65 | MPa |
| Elongation at break (23℃) | ISO 527‑2 | 20‑30 | % | |
| Tensile modulus (23℃) | ISO 527‑2 | 2700‑3000 | MPa | |
| Flexural strength (23℃) | ISO 178 | 68‑89 | MPa | |
| Flexural modulus (23℃) | ISO 178 | 2550‑2600 | MPa | |
| Charpy notched impact (23℃) | ISO 179/1eA | 4.5‑5.3 | kJ/m² | |
| Rockwell Hardness (M‑scale) | ISO 2039‑2 | 80‑82 | — | |
| Thermal Properties | HDT (1.8 MPa) | ISO 75‑2/A | 98‑120 | ℃ |
| Melting point | ISO 3146 | 172 | ℃ | |
| Electrical Properties | Volume resistivity | IEC 60093 | 10¹⁵ | Ω·cm |
| Dielectric strength | IEC 60243 | 25 | kV/mm | |
| Others | UL94 rating(1.0 mm) | UL94 | HB | — |
Injection Molding Parameters
| Process Stage | Parameter | Recommended Range | Unit | Remarks |
|---|---|---|---|---|
| Pre‑treatment | Drying temperature | 80‑90 | ℃ | Drying recommended for better dimension & appearance, avoid bubbles/silver streaks despite low moisture absorption |
| Drying time | 3‑4 | h | ||
| Injection | Rear zone | 160‑180 | ℃ | Narrow processing window; strictly avoid＞230℃, formaldehyde gas will be generated by decomposition |
| Middle zone | 170‑200 | ℃ | ||
| Front zone | 190‑210 | ℃ | ||
| Nozzle temperature | 180‑210 | ℃ | Slightly lower or close to front zone to prevent drooling | |
| Melt temperature | 180‑210 | ℃ | Typical range for copolymer POM‑C | |
| Mold temperature | 60‑90 (up to 120) | ℃ | Higher mold temp improves crystallization, dimensional stability, gloss & reduces sink marks; up to 120℃ for high‑precision parts | |
| Injection pressure | 50‑100 | MPa | Adjust by part geometry & wall thickness | |
| Hold‑up pressure | 30‑80 | MPa | Proper hold‑pressure to reduce shrinkage & sink marks | |
| Back pressure | 0.0‑0.5 | MPa | Keep low; excessive back‑pressure causes shear‑heating degradation | |
| Screw speed | 50‑120 | rpm | Avoid excessive shear heat leading to material decomposition |
Note: All information above is for reference only!
