PMMA Sumitomo Chemical LG2
PMMA Sumitomo Chemical LG2
PMMA Sumitomo Chemical LG2 is high‑flow injection‑molding grade polymethyl methacrylate. It owns excellent optical performance, good heat‑resistance, superior dimensional stability, favorable mechanical properties and processing characteristics.
Main Applications
Thin‑wall & complex‑structure parts: complex frames, large‑area thin wall decorative parts, electronic nameplates, watch faces.
Lighting field: lamp covers, diffusion panels.
Electrical & electronics: LCD & backlight modules, optical lenses, LED lamp housings and other optoelectronic products, electrical appliances.
Consumer goods: cosmetic containers, home‑appliance components, ornaments, household articles.
Properties
表格
| Property Category | Item | Test Standard | Value | Unit |
|---|---|---|---|---|
| Physical | Density | ASTM D792 / JIS K7112 | 1.19 | g/cm³ |
| Water absorption (24 h) | ASTM D570 / JIS K7209 | 0.3 | % | |
| MFR(230℃/3.8 kg) | ASTM D1238 / JIS K7210 | 15 | g/10min | |
| Molding shrinkage (flow direction) | ASTM D955 | 0.20‑0.60 | % | |
| Refractive index | ASTM D542 / JIS K7105 | 1.49 | — | |
| Light transmittance (3.2 mm) | ASTM D1003 / JIS K7105 | 92‑93 | % | |
| Haze | ASTM D1003 / JIS K7105 | 0.5‑1.5 | % | |
| Mechanical | Tensile strength (yield) | ASTM D638 / JIS K7113 | 65‑68 | MPa |
| Flexural strength | ASTM D790 / JIS K7203 | 100‑110 | MPa | |
| Flexural modulus | ASTM D790 / JIS K7203 | 2400‑3100 | MPa | |
| Elongation at break | ASTM D638 / JIS K7113 | 5.0‑7.0 | % | |
| Rockwell hardness‑M | ASTM D785 / JIS K7202 | M94 | — | |
| Izod notched impact(23℃) | ASTM D256 | 1.7‑1.8 | J/m | |
| Charpy notched impact | JIS K7110 | 1.4 | kJ/m² | |
| Thermal | HDT (1.8 MPa) | ASTM D648 / JIS K7207 | 90 | ℃ |
| Vicat softening temperature | ASTM D1525 / JIS K7206 | 95‑101 | ℃ | |
| Linear thermal expansion coefficient | ASTM D696 | 7.0×10⁻⁵ | cm/cm/℃ | |
| Electrical | Volume resistivity | ASTM D257 / JIS K6911 | ＞1.0×10¹⁵ | Ω·cm |
| Surface resistivity | ASTM D257 / JIS K6911 | ＞1.0×10¹⁶ | Ω | |
| Dielectric strength | ASTM D149 / JIS K6911 | 20 | kV/mm | |
| Dielectric constant (60 Hz) | ASTM D150 / JIS K6911 | 3.10 | — | |
| Dissipation factor (60 Hz) | ASTM D150 / JIS K6911 | 0.04 | — | |
| Flammability | UL94 (1.5 mm) | UL94 | HB | class |
Injection‑Molding Parameters
表格
| Process | Item | Recommendation | Notes |
|---|---|---|---|
| Predrying | Drying temperature | 70‑80 ℃ / 85‑90 ℃ | Desiccant dryer required |
| Drying time | 4‑6 h | Target moisture＜0.1%, avoid bubbles & silver‑streaks | |
| Barrel setting | Melt temperature | 238‑272 ℃ / 240‑270 ℃ | Melt temperature dominates filling performance, strictly control residence time to prevent degradation |
| Mold temperature | 34‑71 ℃ / 35‑70 ℃ | Higher temperature improves gloss yet lengthens molding cycle | |
| Injection pressure | High injection pressure | High‑viscosity material; melt temperature has greater influence than injection pressure | |
| Injection speed | Medium | Excessive speed may induce surface defects and internal stress |
Note: Original material sheet leaves barrel zone & nozzle temperature blank, please refer to official TDS for actual production. All data for reference only.
