Results 241 to 250 of about 302,026 (291)

Viscosity index. I. Evaluation of selected copolymers incorporating n‐octadecyl acrylate as viscosity index improvers

Journal of Applied Polymer Science, 1978
AbstractCompositionally and structurally varied copolymers all containing n‐octadecyl acrylate were prepared and evaluated as viscosity index improvers in a common base oil under conditions of low shear. Systems evaluated over a range of copolymer and blend composition were: copolymers of n‐octadecyl acrylate with, respectively, methyl methacrylate, 2 ...
Edmund F. Jordan, Steven Smith, Ronald E. Koos, Winfred E. Parker, Bohdan Artymyshyn, A. N. Wrigley   +5 more
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Latitudes of Viscosity Index Values

Journal of Testing and Evaluation, 1977
Abstract An alternative and simple procedure for the evaluation of numerical precisions of viscosity index values is developed. The procedure extends the former mathematical treatment of Marmin and Sommelet, resulting in greatly simplified equations.
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Boundary Film Formation by Viscosity Index Improvers

Tribology Transactions, 1996
Ultrathin film interferometry has been used to measure the film-forming properties of a range of viscosity index improver (VII) solutions in rolling, concentrated contacts. It has been shown that some VIIs form boundary lubricating films of thickness 10 to 30 nm in contacts.
Matthew Smeeth, Hugh Spikes, Selda Gunsel   +2 more
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A Rating System for Viscosity Index Improvers

SAE Technical Paper Series, 1973
<div class="htmlview paragraph">The purpose of the work reported in this paper was to develop a simple and reliable method of comparing the relative merits of various polymers in a homogeneous sytem of base oils that might be used in multigraded motor oil applications.
J. V. Brancato, Wildrick Hart
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Standard Methods for Calculating Viscosity Index from Kinematic Viscosity

1972
This Standard is issued under the fixed designation D 2270: the number immediately following the designation indicates the year of original adoption or. in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.
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Production and Application Properties of Dispersive Viscosity Index Improvers

Industrial & Engineering Chemistry Research, 2012
Polymeric dispersive viscosity index improvers of lubricating mineral oils based on styrene, dodecyl-methacrylate, octadecyl methacrylate and N, N-dimethylaminoethyl methacrylate (d-PSAMA) were produced by performing copolymerizations isothermally up to the high-conversion in mineral base oil solution, using monofunctional or bifunctional peroxide ...
Šoljić Jerbić, Ivana, Parlov Vuković, Jelena, Jukić, Ante   +2 more
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Table IV. Values for Calculating Viscosity Index from Saybolt Universal Viscosity

1957
This table gives the values of L and D for calculating Viscosity Index from Saybolt Universal viscosities in the range of 40.0 to 350 sec. The values given are based upon Table II of the Standard Method for Calculating Viscosity Index (ASTM Designation: D 567), and are for substitution in Eq 2 of Method D 567.
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Table III. Basic Values for Calculating Viscosity Index from Kinematic Viscosity

1957
Table III gives the basic values of L and D for calculating Viscosity Index from kinematic viscosities in the range of 2.000 to 75.0 cs at 210 F. The values given in Table III are based upon those in Table I of the Standard Method for Calculating Viscosity Index (ASTM Designation: D 567), and are for substitution in Eq 2 of Method D 567.
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Laboratory shearing tests for viscosity index improvers

Tribotest, 1996
AbstractThe relative resistance of VI improvers to breakdown depends on internal structural parameters (chemical type, ratio of monomers, degree of branching) as well as on external factors (test type, duration, severity).Of the many bench tests available to screen shear stability, the 30 cycle CEC injector test is most commonly used for engine oils ...
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Mechanism of action of viscosity index improvers

Tribology International, 1978
Abstract One reason for using polymeric additives is to obtain a product which has better viscosity-temperature characteristics than a comparable pure mineral oil. Measurements of the viscosity-temperature behaviour of motor oils with and without polymer addition show the necessity of a revision of the generally accepted concept of the mechanism of ...
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