viscosity index


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viscosity index

[vi′skäs·əd·ē ‚in‚deks]
(chemical engineering)
An arbitrary scale used to show the magnitude of viscosity changes in lubricating oils with changes in temperature. Abbreviated VI.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
Viscosity index of the base stocks blended with the polymers were measured from the kinematic viscosity data at 313 K and 373 K according to ASTM D 2270-10 method and are presented in Table 3.
The properties of resulted Jatropha biolubricant (kinematic viscosity, pour point and viscosity index)using Paphiaundulata shell as solid catalyst fulfills the biolubricant standard which corresponds to better pour point and viscosity.
Physicochemical test Unit [Value.sub.(exp.)] Iodine value mg KOH/g oil 61.7 Acidity % 3.01 Saponification value mg KOH/g 197.2 Average molecular weight [gmol.sup.-1] 854.3 Unsaponifiable matter % 0.17 Moisture content (Karl Fischer) % 0.22 Cloud point [degrees]C 7 ([+ or -] 1) Pour point [degrees]C 5 ([+ or -] 2) Flash point [degrees]C >320 ([+ or -] 5) Fire point [degrees]C >320 ([+ or -] 5) Oxidative stability (DSC) [degrees]C 179 Kinematic viscosity cSt 45.9 (40[degrees]C) Kinematic viscosity cSt 9.4 (100[degrees]C) Viscosity index n/a 195
Edward Kresge, a pioneer in EP viscosity index modifiers, polyolefin TPEs and tailored MWD EPDMs, was awarded the 2011 Charles Goodyear Medal from the Rubber Division, ACS, at its Spring Technical meeting.
viscosity index, go-synthetic.com/properties/properties.htm.
The viscosity index is calculated based on the cinematic viscosity at 37.8 [degrees]C and 98.9 [degrees]C or at 40 or 100 [degrees]C.
Using a commercial shear rate-controlled rheometer and a commercial texture analyzer, the researchers measured dark chocolate rheological properties (yield stress and apparent viscosity) and textural properties (firmness, viscosity index and hardness).
It also allows quick determination of the viscosity index. Grabner Instruments GmbH www.grabner-instruments.
Viscosity index improvers: These help oils to flow better, particularly when cold.
Soybean oil is a natural lubricant and has a high viscosity index, much better than mineral oil, and is low in volatility, which are ideal traits for lubricants.