400 Commonwealth Drive, Warrendale, PA 15096-0001 U.S.A. Tel: (724) 776-4841 Fax: (724) 776-5760 SAE TECHNICAL PAPER SERIES 2001-01-1994 Viscometric Characteristics of Viscosity Index Improvers - Structural Changes in PAO Solutions at Low Temperature Noely Francisca Pereira and Maria Adelina Santos Araújo PETROBRAS Research and Development Center Alberto Cláudio Habert Universidade Federal do Rio de Janeiro International Spring Fuels & Lubricants Meeting & Exhibition Orlando, Florida May 7-9, 2001Downloaded from SAE International by Stony Brook Univ, Sunday, August 12, 2018The appearance of this ISSN code at the bottom of this page indicates SAE’s consent that copies of the paper may be made for personal or internal use of specific clients. This consent is given on the condition, however, that the copier pay a $7.00 per article copy fee through the Copyright Clearance Center, Inc. Operations Center, 222 Rosewood Drive, Danvers, MA 01923 for copying beyond that permitted by Sec- tions 107 or 108 of the U.S. Copyright Law. This consent does not extend to other kinds of copying such as copying for general distribution, for advertising or promotional purposes, for creating new collective works, or for resale. SAE routinely stocks printed papers for a period of three years following date of publication. Direct your orders to SAE Customer Sales and Satisfaction Department. Quantity reprint rates can be obtained from the Customer Sales and Satisfaction Department. To request permission to reprint a technical paper or permission to use copyrighted SAE publications in other works, contact the SAE Publications Group. No part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without the prior written permission of the publisher. ISSN 0148-7191 Copyright 2001 Society of Automotive Engineers, Inc. Positions and opinions advanced in this paper are those of the author(s) and not necessarily those of SAE. The author is solely responsible for the content of the paper. A process is available by which discussions will be printed with the paper if it is published in SAE Transactions. For permission to publish this paper in full or in part, contact the SAE Publications Group. Persons wishing to submit papers to be considered for presentation or publication through SAE should send the manuscript or a 300 word abstract of a proposed manuscript to: Secretary, Engineering Meetings Board, SAE. Printed in USAAll SAE papers, standards, and selected books are abstracted and indexed in the Global Mobility DatabaseDownloaded from SAE International by Stony Brook Univ, Sunday, August 12, 201812001-01-1994 Viscometric Characteristics of Viscosity Index Improvers - Structural Changes in PAO Solutions at Low Temperature Noely Francisca Pereira PETROBRAS Research and Development CenterMaria Adelina Santos Araújo Alberto Cláudio Habert Universidade Federal do Rio de Janeiro Copyright © 2001 Society of Automotive Engineers, Inc. ABSTRACT The evaluation of the effect of a Viscosity Index Improver (VII) in a mineral oil formulation at low temperaturesbecomes difficult when wax crystallization occurs,which modifies the oil viscosity-temperature behavior. In this work, we studied the isolated influence of VII´s in rheological characteristics of lubricants, using polyalphaolefin (PAO-4) as a wax free base oil.Brookfield viscosity results of the pure PAO-4 werecompared to those of the VII solutions, in fourconcentrations, from –10ºC to –40ºC. The VII thickening power was determined for two commercial polymers from their reduced and intrinsicviscosities in PAO-4 solutions. These parameters werethen used to analyze the low temperature behavior offormulated ATF’s with two kinds of base oils, one Group II and one Group III. The studied VII’s are available in Brazil for the formulation of ATF fluids. INTRODUCTION The specifications for Automatic Transmission Fluids (ATF) have become more and more rigorous, in terms oflow temp