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RT18 PMP Granules
Available Configurations
Properties common to all products in this list
| Weight |
|---|
| 100 g (0.22 lbs) to 20,000 g (44.09 lbs) |
Need custom configurations? Please contact us.
Key Features
RT18 PMP Granules (TPX®) are a specialized grade of polymethylpentene in 3 mm nominal granule form, combining one of the lowest densities of any commercial thermoplastic with outstanding release behavior and optical clarity:
Outstanding Mould Release Behavior
The defining commercial attribute of RT18 PMP. Its surface energy provides clean, repeated release from cured polymer and resin systems without mould release agents, establishing it as the standard substrate for LED encapsulant mould liners, flexible printed circuit backing films, and synthetic leather release paper.
Lowest Density of Any Commercial Thermoplastic (0.835 g/cm³)
At 0.835 g/cm³, RT18 PMP is among the lightest commercial thermoplastics, enabling significant weight reduction in components where density matters alongside the material’s functional properties.
Optical Clarity (Refractive Index 1.463)
High optical transparency combined with a refractive index of 1.463 supports use in packaging for photosensitive materials, optical instrument components, and food-contact packaging where both visual inspectability and chemical inertness are required.
Very Low Moisture Absorption (0.01%)
Near-zero moisture uptake maintains dimensional stability and electrical properties in humid environments, supporting the volume resistivity exceeding 10¹⁶ Ω·cm in service conditions.
Volume Resistivity >10¹⁶ Ω·cm
Exceptional electrical insulation supports use in functional packaging and precision release films for electronic assembly processes where electrostatic behavior and dielectric performance are relevant.
Upper Working Temperature up to 115 °C
Combined with HB flammability rating and resistance to greases, oils, acids, alkalis, and alcohols, this supports precision release film and functional packaging applications in demanding thermal environments.
Industrial Applications
RT18 PMP Granules are used wherever low density, optical clarity, outstanding release behavior, and chemical resistance must be combined in a thermoplastic processable by injection moulding and extrusion:
- ✦ LED Encapsulant Mould Liners
- The primary application. RT18 PMP’s outstanding release from cured epoxy and silicone encapsulants allows repeated demoulding without adhesion or surface contamination of the LED package, making it the standard liner material for high-volume LED encapsulation tooling.
- ✦ Flexible Printed Circuit Backing Films
- Applied as backing films in flexible printed circuit fabrication, where clean release from the cured circuit laminate and dimensional stability during processing are both required.
- ✦ Synthetic Leather Release Paper
- Used as a release substrate in synthetic leather production, where repeated, clean separation from the leather surface finish layer is required across extended production runs.
- ✦ Packaging for Photosensitive Materials
- Optical transparency and chemical inertness to acids, alkalis, and alcohols make it suitable for packaging containers where visual inspection of contents and protection from chemical exposure are both required.
- ✦ Custom Release Tooling and Lightweight Structural Parts
- Processed by injection moulding and extrusion into custom release tooling, optical components, and lightweight structural parts where the combination of low density, clarity, and surface release behavior is operationally valuable.
Material Properties
| Element | Value |
|---|---|
| Acids - concentrated | Good-Fair |
| Acids - dilute | Good |
| Alcohols | Good |
| Alkalis | Good |
| Aromatic hydrocarbons | Fair-Poor |
| Greases and Oils | Good-Fair |
| Halogenated Hydrocarbons | Fair-Poor |
| Halogens | Fair-Poor |
| Ketones | Good-Fair |
| Element | Value |
|---|---|
| Dielectric constant @1MHz | 2.12 |
| Dissipation factor @ 1kHz | 0.0002 |
| Volume resistivity( Ohmcm ) | >10¹⁶ |
| Element | Value |
|---|---|
| Flammability | HB |
| Refractive index | 1.463 |
| Resistance to Ultra-violet | Poor |
| Limiting oxygen index( % ) | 17 |
| Water absorption - over 24 hours( % ) | 0.01 |
| Density( gcm⁻³ ) | 0.835 |
| Element | Value |
|---|---|
| Hardness - Rockwell | R85 |
| Elongation at break( % ) | 15 |
| Tensile modulus( GPa ) | 1.5 |
| Izod impact strength( J m⁻¹ ) | 49 |
| Tensile strength( MPa ) | 25.5 |
| Element | Value |
|---|---|
| Heat-deflection temperature - 0.45MPa( C ) | 100 |
| Heat-deflection temperature - 1.8MPa( C ) | 40 |
| Lower working temperature( C ) | 20 |
| Upper working temperature( C ) | 75-115 |
| Specific heat( J K⁻¹ kg⁻¹ ) | 2000 |
| Thermal conductivity( W m⁻¹ K⁻¹ ) | 0.17@23°C |
| Coefficient of thermal expansion( x10⁻⁶ K⁻¹ ) | 117 |