The Future of Specialty Siloxane Copolymer Lubricants

By Chad Chichester

A behind-the-scenes look at how Molykote® brand from The Dow Chemical Company is paving the way for innovations in high-temperature automotive and industrial appliance and maintenance applications.

The Molykote® brand from The Dow Chemical Company has been synonymous with cutting-edge technology in speciality silicone lubricants for nearly 70 years. In exploring the future needs of an automotive and industrial appliance and maintenance markets, the company continuously works with design and maintenance engineer customers, providing solutions that push boundaries of science and technology to deliver lubrication performance, reliability and cost-savings. The launch of Molykote G-900x Series greases represents unprecedented innovation in silicone lubrication, opening up new opportunities and possibilities in the world of speciality, high-performance lubricants. This patented class of silicone lubricants was developed as a cost-attractive solution for extreme temperature, environment and speed requirements.  

High-Temperature Lubricity, Without Sacrifice

Molykote G-900x Series greases, including G-9000 and G-9001, offer high-temperature lubricity without sacrificing low-temperature performance. Combining phenyl methyl and fluoro functional branches to a siloxane backbone offers optimized thermal stability and wear resistance, in a copolymer used in Molykote G-900x greases, resulting in unique properties, including:

High thermal stability across a wide temperature range (-35 to 220 degrees Celsius) Compatible with most plastics and elastomers Density of 1.4 g/cm3 Increased application lifetime due to high thermal and oxidative stability Good corrosion resistance Formulation capabilities with various thickener systems

A Behind-the-Scenes Look at Silicone Science

In the 1960s, Dow Corning Corporation (now a wholly owned subsidiary of The Dow Chemical Company) developed phenyl methyl siloxane fluids, which exhibit very good low- and high-temperature performance properties, but lacked lubricious qualities and the ability to carry loads due to its flexible and compressible nature. In the 1970’s fluoro siloxanes were developed, having lower compressibility, for better load carrying.

The idea behind the copolymer used in Molykote G-900x greases is to combine phenyl and fluoro functional groups on the same oxidatively stable silicone—SiO— polymer chain. This differs from blending a phenyl and flouro fluid. The copolymer creates one molecule combining the properties of phenyl and trifluoropropyl as a base fluid for lubricants.

Filling a Gap in the Marketplace

Molykote G-900x Series greases are a cost-attractive solution for applications that do not require the ultimate high-temperature performance of perfluoropolyether (PFPE) greases and where ester-based lubricants are limited in temperature. Thinking about lubricant performance and application in a pyramid layout, most uses are accomplished with mineral oils at the bottom of the pyramid. At the top are PFPEs, which have fantastic performance attributes, but are costly and very specialized to applications that require highly oxidative and thermal properties. The Molykote G-900x Series copolymer fits within the middle space between traditional silicones and PFPEs.

The copolymer also offers an advantage from a density perspective compared to PFPEs, providing nearly twice the volume for the same weight and lower specific gravity, resulting in better mobility, greater value and more lubrication from less material. It also enhances performance in applications where high-bearing speed or total mass are critical.

With improved acceptance for additives, such as anti-wear, anti-oxidation and extreme pressure, the product lineallows expanded formulation flexibility compared to other silicone-based lubricants where additives are not soluble.

The Many Applications of Molykote brand products

The Molykote G-900x Series greases are suitable for numerous high-temperature lubricant applications, including:

High-temperature bearings Tire molding Automotive powertrain components Carton board manufacturing equipment Metal processing Injection moulding equipment Oil and gas

The Future of Specialty Lubricants

The Molykote brand from The Dow Chemical Company has long been trusted worldwide for solving difficult lubrication challenges in reducing friction and wear. We consider our line-up of base fluid technologies as a set of tools; the Molykote G-9000 Series greases is the latest tool in our quest for innovative new lubricants for high-temperature applications. We believe that this patented technology could very well change the way the industry thinks about speciality lubricants today and in the future. i

Author: Chad Chichester is Molykote® Lubricants Application Engineering Specialist from The Dow Chemical Company.