[Due to the increasing size of the archives, each topic page now contains only the prior 365 days of content. Access to older stories is now solely through the Monthly Archive pages or the site search function.]
Northwestern researchers discover crumpled graphene balls are a promising lubricant additive
January 26, 2016
Researchers at Northwestern University’s McCormick School of Engineering have found that crumpled graphene balls are an extremely promising lubricant additive. In a series of tests, a polyalphaolefin base oil with only 0.01–0.1 wt % of crumpled graphene balls outperformed a fully formulated commercial lubricant in terms of friction and wear reduction. A paper on their work is published in the Proceedings of the National Academy of Sciences.
For the average car, 15% of the fuel consumption is spent overcoming friction in the engine and transmission. While oil helps reduce this friction, researchers have long sought additives that enhance oil’s performance. Ultrafine particles are often used as lubricant additives because they are capable of reducing friction and protecting surfaces from wear. They also tend to be more stable than molecular additives under high thermal and mechanical stresses during rubbing. However, they also can aggregate, reducing the effective concentration.
Amyris/Cosan JV Novvi introduces 100% renewable Group III and IV base oils
May 27, 2015
Novvi LLC, a joint venture of Amyris, Inc. and Cosan S.A. Industria e Comercio, unveiled two new 100% renewable base oil—the main component of motor oils—products: a renewable polyalphaolefin (PAO) Group IV and a renewable version of its NovaSpec Group III+ base oil. The new base oil products add to Novvi’s growing portfolio of renewable oils.
The Novvi JV was created to develop, produce, market, and distribute high-performance oils and lubricants from renewable sources. Novvi applies Amyris’ synthetic biology platform to produce targeted hydrocarbon molecules from plant sugar and Cosan’s feedstock capabilities and supply and distribution infrastructure.
Penn and ExxonMobil researchers uncover mechanisms behind performance of major antiwear additive in lubricants
March 13, 2015
One of the main modern antiwear lubricant additives is zinc dialkyldithiophosphate (ZDDP)—widely used in automotive lubricants—which forms crucial antiwear tribofilms at sliding interfaces. However, despite its importance in prolonging machinery life and reducing energy use, the mechanisms governing its tribofilm growth are not well-understood. This limits the development of replacements with better performance and catalytic converter compatibility.
Now, in a study published in the journal Science, researchers from the University of Pennsylvania and ExxonMobil, have uncovered the mechanisms governing the growth of ZDDP antiwear tribofilms at sliding interfaces. The study provides a way forward for scientifically testing new anti-wear additives. Being able to pinpoint the level of stress at which they begin to break down and form tribofilms allows researchers to compare various properties in a more rigorous fashion.
Sub-micrometer carbon spheres as oil additives reduce engine friction up to 25%
March 06, 2015
Researchers at Purdue University have shown that adding ultra-smooth submicrometer carbon spheres to motor oil can reduce friction and wear typically seen in engines by up to 25%. The researchers also have shown how to potentially mass-produce the spheres, making them hundreds of times faster than previously possible using ultrasound to speed chemical reactions in manufacturing.
In a paper in the ACS journal Advanced Materials & Interfaces, they reported that the new lubricant composition—3% carbon spheres suspended in a reference SAE 5W30 engine oil—exhibited a substantial reduction in friction and wear (10 to 25%) compared to the neat oil, without change in the viscosity. Friction reduction was dependent on the sliding speed and applied load, and maximum reduction was achieved at the highest sliding speed in the boundary lubrication regime.