High-Performance Thermal Management Fluids

Pdms Silicone Oil For Heat Transfer Applications

Engineered Polydimethylsiloxane (PDMS) fluid solutions offering superior thermal stability, wide operational temperature windows (-50°C to +250°C+), excellent dielectric strength, and non-corrosive heat exchange performance across modern industrial and electronics ecosystems.

Core Product Solutions

Precision Heat Transfer & Functional Silicone Fluids

Explore our flagship PDMS silicone fluid grades and modified organosilicon structures tailored for demanding single-phase and closed-loop heat transfer systems.

Primary Heat Transfer Oil

POLYDIMETHYL SILOXANES (PDMS) CAS Number: 63148-62-9

Pure methyl silicone fluid offering extreme thermal resistance, low vapor pressure, and exceptional dielectric properties for liquid cooling.

Thermal Elastomer & Fluid Base

Vinyl Silicone Oil CAS Number: 70900-21-0

Reactive vinyl-terminated polysiloxane utilized in high-temperature thermal pad formulations and crosslinkable heat conduction matrices.

Crosslinking & Hydrophobic Agent

Methyl Hydrogen Silicone Fluid (MH Fluid)

Active Si-H bond silicone fluid used for specialized hydrophobic heat exchanger surface treatments and structural crosslinking.

Specialty Thermal Intermediate

Hydrogen-terminated silicone oil

Telechelic Si-H functionalized silicone fluid delivering controlled molecular weight distribution for advanced thermal interface polymers.

Engineering Fundamentals

The Thermophysical Superiority of Polydimethylsiloxane (PDMS) Fluids

Polydimethylsiloxane (PDMS), designated by CAS Number 63148-62-9, represents the gold standard in synthetic organosilicon thermal fluids. Formed by repeating silicon-oxygen linkages (–Si(CH3)2–O–) terminated with trimethylsiloxy groups, PDMS possesses an exceptionally high siloxane backbone bond energy (445 kJ/mol). This molecular configuration endows PDMS silicone oils with thermal stability vastly superior to conventional petroleum-derived mineral oils and synthetic hydrocarbon alternatives.

In thermal management and secondary heat transfer circuits, PDMS fluids operate smoothly across broad thermal bandwidths—frequently between -50°C and +200°C in open atmospheric environments, and extending beyond +250°C in inertized, closed-loop pressurized loops without thermal cracking or sludge formation.

Key Thermophysical Advantages:

Flat viscosity-temperature gradient (low VTC), high flash and fire points (>300°C for higher viscosities), dielectric breakdown strength exceeding 35 kV, negligible vapor pressure, and non-corrosive compatibility with stainless steel, copper alloys, and engineering polymers.

Because of its non-toxic, chemically inert, and PFAS-free composition, PDMS has rapidly evolved from a niche specialty chemical into a cornerstone liquid coolant for advanced electrification, semiconductor manufacturing, and green chemical synthesis.

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Minimal Viscosity Variation Across Extreme Temperatures

Unlike organic fluids that thicken drastically at sub-zero temperatures or degrade at elevated heat, PDMS maintains pumpability at cryogenic thresholds while preserving adequate boundary lubrication and high thermal transfer coefficients at high temps.

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Zero Carbon Residue & Extended Service Life

Under continuous thermal cycles, PDMS silicone oil resists oxidative polymer breakdown, eliminating the formation of carbonaceous coking, varnish, and acidic byproducts that routinely foul heat exchange coils and pump seals in mineral-based circuits.

Market Insights & Dynamics

Commercial Evolution & Strategic Drivers in Heat Transfer

The global heat transfer fluids market is undergoing a structural paradigm shift driven by stringent decarbonization targets, data center electrification, and the global phase-down of hazardous fluorinated chemicals (PFAS).

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AI Data Centers & Hyperscale Immersion Cooling

Modern AI server clusters consuming over 50–100 kW per rack demand high-efficiency single-phase liquid immersion cooling. Ultra-low viscosity PDMS silicone fluids (5 cSt – 20 cSt) provide the high dielectric isolation, low volatility, and zero-corrosion reliability needed to cool dense compute nodes safely.

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PFAS Phase-Out & Eco-Regulatory Compliance

With environmental bodies (such as EU REACH and the US EPA) accelerating restrictions on fluorinated "forever chemicals" (PFAS / PFPE / HFE coolants), PDMS silicone oil has emerged as the premier non-toxic, zero-ODP, ultra-low GWP, and bio-compatible alternative for industrial heat exchange.

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EV Battery & Fast-Charging Thermal Management

Electric vehicle (EV) battery packs and mega-watt ultra-fast charging stations require active thermal fluids capable of maintaining pack temperatures between 20°C and 35°C during rapid discharge, preventing thermal runaway while ensuring zero electrical conductive risk.

Fluid Technology	Operating Temp Range	Dielectric Breakdown	Thermal Degradation & Coking	Environmental / PFAS Profile	Lifecycle Cost Efficiency
PDMS Silicone Oil (CAS 63148-62-9)	-50°C to +250°C+	> 35 kV / 2.5mm	Virtually Zero Coking (Clean)	Non-PFAS, Zero ODP, Non-Toxic	High (Long Drain Intervals >10 Yrs)
Standard Mineral Oil	-10°C to +150°C	20 - 30 kV	High Oxidation & Sludge Build-up	Hydrocarbon emissions, flammable	Low Initial, High Maintenance
Synthetic Aromatic (Therminol/Dowtherm)	-20°C to +320°C	Low / Non-Dielectric	Moderate Cracking, Pungent Odor	VOC risks, hazardous waste disposal	Medium
Fluorinated Liquids (PFAS / PFPE)	-80°C to +200°C	> 40 kV	Clean, High Evaporation Loss	Global PFAS Restrictions & High GWP	Extremely Expensive

In-Depth Case Studies

High-Impact Industrial Application Scenarios

From cryogenic laboratory chillers to multi-megawatt pharmaceutical batch reactors, PDMS silicone fluids deliver uncompromising thermal precision.

SCENARIO 01

Data Center & HPC Immersion Cooling

PDMS silicone oil functions as a single-phase dielectric heat transfer coolant for high-density compute boards, direct-to-chip heat exchangers, and immersion tanks. Its low surface tension ensures thorough micro-channel wetting, while non-reactive compatibility shields delicate solder joints and optical transceivers from damage.

Dielectric Coolant Single-Phase PUE < 1.05

SCENARIO 02

Pharmaceutical & Fine Chemical Reactors

Jacketed batch reactors in Active Pharmaceutical Ingredient (API) synthesis require rapid temperature swings from cryogenic crystallization (-70°C) to high-temperature reflux (+180°C). PDMS enables single-fluid operation across the entire cycle, eliminating dual-loop cross-contamination risks.

API Synthesis Wide Thermal Band GMP Compliant

SCENARIO 03

Semiconductor Test Benches & Etch Chillers

Plasma etch tools and automated test equipment (ATE) demand micro-Kelvin thermal stability. PDMS fluids deliver low hydraulic resistance and laminar flow stability, preventing temperature fluctuations during ultra-fast wafer processing.

Wafer Chuck Cooling High Purity Semiconductor

SCENARIO 04

Solar Thermal & Geothermal Systems

In closed-loop concentrated solar power (CSP) and secondary geothermal heat recovery systems, silicone oils withstand intense solar irradiation and high-temperature cycling without thermal decomposition or gaseous vapor lock.

CSP Solar Zero Vapor Lock Renewable Energy

SCENARIO 05

Food Processing & Packaging Extrusion

High-temperature food frying, sterilization tunnels, and plastic thermoforming utilize PDMS heat transfer fluids. Their odorless, tasteless, non-toxic, and high-flashpoint profiles significantly reduce plant fire hazards and regulatory contamination risks.

Food-Grade Safe Odorless Thermoforming

SCENARIO 06

High-Voltage Transformers & Switchgear

Serving as both an arc-quenching dielectric insulating fluid and an efficient convection coolant, silicone oil enhances the fire safety rating and operational life of indoor traction transformers, substations, and offshore wind turbines.

Dielectric Insulator K-Class Fluid Fire Safety

Design & Formulation Guide

Selecting the Optimal PDMS Viscosity Grade for Heat Exchange

Viscosity is the most decisive physical property governing heat transfer coefficients, hydraulic pressure drops, and pumping energy consumption in silicone oil systems.

Low Viscosity Grades (5 cSt to 20 cSt): Characterized by high turbulent Reynolds numbers, rapid heat convection, and minimal pumping power requirements. Recommended for closed-loop micro-channel liquid cooling, electronics immersion, and cryogenic thermostats down to -50°C.
Medium Viscosity Grades (50 cSt to 100 cSt): Offer the optimum balance between elevated flash points (>300°C), low volatility, and fluid lubricity. Widely implemented in pharmaceutical jacketed reactors and high-temperature bath circulators.
High Viscosity Grades (200 cSt to 1000 cSt): Tailored for thermal damping, mechanical shock absorption, and high-temperature static heat conduction baths where fluid agitation is secondary to thermal persistence.

Proper system engineering requires nitrogen blanketing (inert gas shielding) when operating near maximum thermal thresholds to prevent long-term silanol condensation and maintain peak dielectric insulation.

Thermal Performance Calculations:

The convective heat transfer performance of PDMS fluid is dictated by the Nusselt number ($Nu$), which depends on the fluid's thermal conductivity ($k \approx 0.13 - 0.16\text{ W/m}\cdot\text{K}$), specific heat capacity ($C_p \approx 1.45 - 1.65\text{ J/g}\cdot\text{K}$), and kinematic viscosity.

Because PDMS exhibits Newtonian fluid behavior across wide shear rates, system designers can accurately model pressure drops ($\Delta P$) using standard Darcy-Weisbach equations without non-linear flow disruptions.

Engineering Recommendation:

For immersion cooling and rapid-exchange circuits, select Bayeechem PDMS 10 cSt or 20 cSt fluids to maximize heat flux while maintaining safety flashpoints above 170°C–230°C.

About Hangzhou Bayee Chemical Co., Ltd.

Welcome to Bayee – 25+ Years of Chemical Excellence

Hangzhou Bayee Chemical Co., Ltd. started chemical products exporting from 2001, manufacturers based exporter focused in chemical products covering Silicone series, Phosphorus series including Silicone Monomers, Cyclosiloxane, Silicone Oils, Agro Chemicals, Fire Retardants & Auxiliaries etc. Company has direct Import & Export right, Dangerous Cargo Permission Certificate. Based on 20+ years exporting history and persistent improvements, we have now grown and developed into a well known & good reputation exporter with ISO 9001:2015, AAA Credit certified company, also granted by local government as Healthy Enterprise, and A level Tax Ranking.

Business Licence No. / Social Credit Code: 91330108759549090L
Dangerous Cargo Certificate No.: [2025] 06002608
Import & Export Certificate No.: 02306457
AAA Credit Rating No.: BRC24AAA10012R2S
ISO:9001 Certificate: BRC2024Q10513R2S

25⁺

Years R&D and Production Experience

Strategic Production Synergy & Quality Control

Based on strategic factories in Zhejiang, Jiangsu, Shandong, Anhui, Jiangxi, Hubei, Hunan, Hebei and Henan provinces etc, we export not only good quality products, competitive EXW costs, but also honesty, safety and international philosophies to customers. We work tightly with competitive production sites across whole China, who have special advantages, located in professional industrial areas, close to raw material bases, locally supplied with energy - gas or steam pipe connected with neighbour enterprises in same areas to reduce transportation costs. Our factories have advanced ideas in technique crafts for higher yield production, unit consumption reducing from raw materials, also re-used the by-products for own downstream production for other products. By the way, we always keep close observation about raw material changing trend, react actively with factories shoulder by shoulder from organizing raw material at good times to secure more competitive production costs and share spaces with customers helping win their market shares. At the same time, we have wide connection with Chinese powerful chemical institute organizations for testing and supervising quality control in production process.

GLOBAL BUSINESS FOOTPRINT

Up till now we’ve developed and supplied to many countries and areas all over the world, with main markets in European countries (Germany, Italy, UK, Spain, Ukraine, Russia, Poland, etc.), USA, South America, Mid East, South-east Asia, Australia, etc. Also seeking more strategic partners and customers under mutual benefits and work through the whole purchasing chain.

🌍 Germany & Western Europe 🌍 United States & North America 🌍 Italy & Spain 🌍 Poland & Eastern Europe 🌍 South America 🌍 Middle East & GCC 🌍 Southeast Asia & Australia

Complete Silicone Fluid Catalog

Comprehensive Heat Transfer & Organosilicon Product Portfolio

Select from our complete range of pure PDMS silicone oils, reactive silicone fluids, and functional oligomers designed for heat conduction, chemical formulation, and industrial thermal loops.

Heat Transfer Core

POLYDIMETHYL SILOXANES (PDMS) CAS Number: 63148-62-9

Standard and low-viscosity polydimethylsiloxane fluid engineered for continuous thermal stability and dielectric immersion cooling.

Hydrophobic Surface Treatment

Methyl Hydrogen Silicone Fluid (MH Fluid)

High-activity Si-H fluid used to impart water repellency and anti-fouling characteristics to industrial heat exchangers.

Functional Emulsion & Additive

BY-209 Amino-modified silicone fluid

Amino-functionalized siloxane offering outstanding interfacial affinity, softness, and specialty thermal coating performance.

High-Temp Crosslinkable Base

Vinyl Silicone Oil CAS Number: 70900-21-0

Vinyl-terminated fluid utilized as the primary matrix in heat-conductive potting compounds and thermal interface pads.

Hydrosilylation Reactive Fluid

Hydrogen-terminated silicone oil

Precision-terminated Si-H polysiloxane for synthesizing advanced block copolymer thermal materials and specialty elastomers.

Hydroxyl Condensation Base

OH-Hydroxy, Terminated Silicone Fluid

Silanol-terminated (OH) reactive silicone fluid utilized in high-temperature sealants, thermal coatings, and dielectric insulators.

Immersion Cooling Grade

PDMS Dielectric Liquid Coolant (5-50 cSt)

Specialized ultra-pure PDMS cut optimized for data center immersion, low-temperature pumping efficiency, and zero residue.

Specialty Thermal Formulations

Organo-Modified Silicone Thermal Fluid Series

Custom organosilicon fluid grades engineered for high-compatibility lubrication, thermal boundary layers, and synthetic textile processing.

Accelerate Your Thermal Engineering Projects With Bayee

Whether you require bulk supply of ultra-low viscosity PDMS for next-generation data center immersion cooling or customized organosilicon fluids for high-temperature synthesis, our technical specialists and ISO 9001:2015 certified export infrastructure are ready to assist.

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