LiPOLY’s T-top99-s is the highest thermal conductivity pad in the Extreme Series lineup, rated at 24.0 W/m·K per ASTM D5470. That figure places it at the top of LiPOLY’s gap-filler portfolio and among the most thermally conductive silicone pads available anywhere. For applications where every fraction of a degree matters—5G base station infrastructure, high-end chips, and densely packed telecommunications hardware—the T-top99-s is designed to move heat away from critical components as efficiently as a pad can.
The T-top99-s sits in LiPOLY’s Extreme Series, which includes the T-work7000, T-work8000, and T-work9000 pads. Each step up the series delivers progressively higher thermal conductivity, and the T-top99-s represents the ceiling of that progression at 24.0 W/m·K (ASTM D5470). It also carries an ISO 22007-2 conductivity rating of 15.0 W/m·K, giving engineers two standard reference points to work from depending on which test method their design validation uses. The pad is engineered for uneven surface applications, filling micro gaps and reducing contact thermal resistance between heat-generating components and their heat sinks.
T-top99-s Specifications
The T-top99-s is a gray, silicone-based thermal pad with a density of 3.3 g/cm³ and a hardness of 70 Shore OOO. Its thermal impedance is rated at 0.085 °C-in²/W at 10 psi, which is among the lowest impedance figures in the LiPOLY catalog. The pad offers a high compression rate and is available with either one-side or two-side surface tack (option 2), giving designers flexibility in how the pad is seated during assembly. Thickness is customized to the application per ASTM D374. The material operates across a wide temperature range of -60°C to 150°C, and total mass loss (TML) is held below 0.1%, indicating minimal outgassing even at elevated operating temperatures. The T-top99-s is fully ROHS and REACH compliant.
Typical properties:
- Thermal conductivity (ASTM D5470): 24.0 W/m·K
- Thermal conductivity (ISO 22007-2): 15.0 W/m·K
- Thermal impedance: 0.085 °C-in²/W @ 10 psi
- Color: Gray
- Surface tack: 2-side / 1-side, option 2
- Thickness: Customized (ASTM D374)
- Density: 3.3 g/cm³ (ASTM D792)
- Hardness: 70 Shore OOO (ASTM D2240)
- TML: <0.1%
- Application temperature: -60°C to 150°C
- Compliance: ROHS & REACH compliant
- Configurations: Sheet form, die-cut parts
Download the T-top99-s datasheet here (LiPOLY product page).
Applications Where T-top99-s Excels
The combination of ultra-high thermal conductivity, low impedance, and high compressibility makes the T-top99-s suitable for the most thermally demanding applications in electronics. The pad conforms to uneven surfaces and fills micro gaps that would otherwise trap air, which is a poor thermal conductor. Common applications include:
- Between CPU and heat sink — high-conductivity transfer from the processor to the thermal solution
- Between a component and heat sink — general-purpose interface for power components
- Flat-panel displays — thermal management for display driver ICs and backlight assemblies
- Power supplies — heat dissipation from power conversion circuitry
- High speed mass storage drives — cooling for SSD controllers and NAND packages
- Telecommunication hardware — thermal interface in densely packed RF and baseband assemblies
- 5G base station & infrastructure — managing heat in outdoor, high-ambient enclosures
- High-end chips — top-tier thermal interface for flagship silicon
In addition to its thermal performance, the T-top99-s is an excellent electrical insulator. This matters in applications where the heat sink or cooling structure is at a different electrical potential than the component being cooled. The pad’s insulation properties allow it to be used between live components and grounded heat sinks without requiring an additional insulating layer, simplifying assembly and reducing the total number of interfaces in the thermal path. Fewer interfaces means lower cumulative thermal resistance.
T-top99-s and the LiPOLY Extreme Series
The T-top99-s is part of LiPOLY’s Extreme Series, a family of high-performance thermal pads that scale from the T-work7000 at the entry point to the T-top99-s at the top. The T-work7000 provides a solid mid-range conductivity option for general thermal management. Stepping up, the T-work8000 increases conductivity for more demanding applications. The T-work9000 pushes conductivity further still for high-power density designs. The T-top99-s sits above all three at 24.0 W/m·K (ASTM D5470), making it the go-to choice when the other Extreme Series pads do not quite meet the thermal budget. All four pads share the same silicone-based construction, excellent compressibility, and electrical insulation characteristics—the primary differentiator across the series is thermal conductivity and the impedance that follows from it.
Custom Die-Cut Supply Through NEDC
NEDC is an authorized converter of LiPOLY thermal products, including the full Extreme Series. We supply the T-top99-s in custom die-cut parts to exact customer specifications, whether that means complex geometries for a specific CPU footprint, kiss-cut parts on a roll for high-volume assembly, or sheet form for in-house conversion. NEDC operates precision flatbed and rotary die-cutting equipment capable of holding tight tolerances on thermal pad materials. If you have a drawing, a CAD file, or even a sample part, we can produce the T-top99-s in the exact shape and thickness your application requires. NEDC can also assist with material selection across the LiPOLY range—if the T-top99-s is more conductivity than your thermal budget demands, we can recommend the appropriate Extreme Series alternative.
For more information on the full range of thermal interface materials available, visit our thermal pads page.
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Need a custom T-top99-s die-cut part? Contact NEDC with your specifications.