General NOMEX Information: Nomex® is a family of aromatic polyamide (aramid) fibers. This family consists of staple fibers, continuous filament yarns, paper, and spunlaced fabrics. The paper is produced from two forms of the aramid polymer. Small fibrous binder particles (fibrids) derived directly from the polymer under high shear conditions are mixed with short fibers (floc) which are cut to length from a fiber filament. The floc and fibrids are combined in a water based slurry from which a continuous sheet is produced on a specialized papermaking machine. This initial paper (as in Type 411) is low density and has poor properties. Subsequent densification and internal bonding is achieved by high temperature calendaring. The resulting paper is mechanically strong and has good electrical properties. Some uses for paper product include insulation in electric motors and transformers, wire wrapping, and honeycombed strength members in many aircraft. Nomex® brand fibers are inherently flame resistant: the flame resistance is a polymer property and does not diminish with the life of the fiber.
Nomex® meta-aramid, poly(meta-phenyleneisophthalamide), is prepared from meta-phenylenediamine and isophthaloyl chloride in an amide solvent. It is a long chain polyamide in which at least 85% of the amide linkages are attached directly to two aromatic rings. The meta oriented phenylene forms bends in the polymer chain, reducing chain rigidity as compared to the para orientation in the chemically similar Kevlar® chain. This flexible polymer chain gives Nomex® more textile-like qualities while retaining high temperature properties similar to Kevlar®.
Information provided by DuPont.
物理性能 | 额定值 (公制) | 额定值 (英制) | 测试方法 |
---|---|---|---|
体积密度 | g/cc | lb/in³ | |
密度 | g/cc | lb/in³ | |
厚度 | microns | mil | Nominal |
microns | mil | Typical; ASTM D374 |
机械性能 | 额定值 (公制) | 额定值 (英制) | 测试方法 |
---|---|---|---|
断裂伸长率,MD | ASTM D828 | ||
断裂伸长率,TD | ASTM D828 | ||
Tear Strength, Total | N | lb (f) | Initial in TD; ASTM D1004 |
N | lb (f) | Initial in MD; ASTM D1004 | |
抗张强度(MD : 断裂) | MPa | psi | Calculated from mfr's report of 224 N/cm per ASTM D828 and the typical thickness |
抗张强度(TD : 断裂) | MPa | psi | Calculated from mfr's report of 116 N/cm per ASTM D828 and the typical thickness |
电气性能 | 额定值 (公制) | 额定值 (英制) | 测试方法 |
---|---|---|---|
介电常数 | @Frequency 60 Hz | @Frequency 60 Hz | ASTM D150 |
介电强度 | kV/mm | kV/in | AC Rapid Rise; ASTM D149 |
kV/mm | kV/in | Full-wave Impulse; ASTM D3426 | |
耗散因数 | @Frequency 60 Hz | @Frequency 60 Hz | ASTM D150 |
热性能 | 额定值 (公制) | 额定值 (英制) | 测试方法 |
---|---|---|---|
导热系数 | W/m-K @Temperature 150 °C | BTU-in/hr-ft²-°F @Temperature 302 °F | measured on 10 mil sample |
最高工作温度, Air | °C | °F | 220°C insulation by UL |