How Do Functionalized MWCNTs Affect the Thermal Conductivity of Nanofluids
2026-06-09
Thermal management is critical in advanced industries. Functionalized MWCNTs have emerged as superior additives for nanofluids due to their enhanced dispersion and interfacial bonding. At SAT NANO, we specialize in high-quality Functionalized MWCNTs that significantly boost heat transfer efficiency.
Mechanism of Thermal Conductivity Enhancement
Functionalized MWCNTs reduce interfacial thermal resistance by introducing covalent bonds (e.g., -COOH, -OH) on their surfaces. These bonds minimize phonon scattering and improve particle-fluid interaction. Below is a comparison between pristine and functionalized types:
| Property | Pristine MWCNTs | Functionalized MWCNTs |
|---|---|---|
| Dispersion in Base Fluids | Poor (agglomerates) | Excellent (stable) |
| Thermal Conductivity Increase | 10–15% | 25–40% |
| Interfacial Thermal Resistance | High | Low |
| Long-term Stability | Days | Months |
Key Application Data
Nanofluids with Functionalized MWCNTs show superior performance in coolants, electronics cooling, and solar thermal systems. A typical 0.5 wt% loading of SAT NANO’s Functionalized MWCNTs in water or ethylene glycol yields a 32% thermal conductivity rise compared to base fluids.
Functionalized MWCNTs FAQ
Q1: Why do Functionalized MWCNTs perform better than pristine ones in thermal nanofluids?
A1: Pristine MWCNTs tend to bundle due to van der Waals forces, creating phonon barriers. Functionalized MWCNTs carry polar groups that electrostatically repel each other and chemically anchor to fluid molecules. This reduces aggregation and Kapitza resistance, enabling a continuous phonon transfer pathway. As a result, thermal conductivity gains are consistent and reproducible.
Q2: Can Functionalized MWCNTs be used in oil-based nanofluids for high-temperature applications?
A2: Yes. Functionalized MWCNTs with lipophilic surface groups (e.g., alkyl or amine chains) disperse uniformly in mineral oils, synthetic oils, and dielectric fluids. SAT NANO offers custom functionalization for up to 300°C operation. The functional layer prevents oxidation and sedimentation, maintaining thermal conductivity enhancement even after 500 thermal cycles.
Q3: What is the optimal concentration of Functionalized MWCNTs to avoid viscosity trade-offs?
A3: The ideal range is 0.1–0.8 wt%. Below 0.1 wt%, thermal benefits are minimal. Above 0.8 wt%, viscosity rises disproportionately, reducing flow and convective heat transfer. SAT NANO recommends 0.4–0.6 wt% for most water-based systems, yielding a 28–35% thermal conductivity improvement with only a 10% viscosity increase. A rheology test prior to scale-up is advised.
Contact Us
Ready to integrate Functionalized MWCNTs into your thermal fluids? SAT NANO provides customized functionalization, technical datasheets, and bulk pricing. Contact us today at [email protected] or visit our website to discuss your nanofluid formulation. Let SAT NANO drive your heat transfer innovation.
