Synthesis, Characterization, and Evaluation of Polyisobutylene-Based Imido-Amine-Type Dispersants Containing Exclusively Non-Nucleophilic Nitrogen

Document Type

Article

Publication Date

8-1-2018

Department

Polymers and High Performance Materials

Abstract

Lubricating oils for gasoline and diesel engines are formulated to include amphiphilic dispersants for soot particle stabilization and prevention of particle aggregation. Primary and secondary amines used within the polar group of traditional dispersants provide basic nitrogen, which is able to neutralize acidic by‐products from combustion and does not contribute to sulfated ash. However, these active‐hydrogen‐containing amines present significant problems for fluoroelastomer seals and metals in terms of degradation and corrosion. Polyisobutylene (PIB)‐based dispersants containing only tertiary amines, intended to remediate these problems, were synthesized from primary‐bromide‐terminated PIB, 1‐(2‐aminoethyl)piperazine, and an anhydride such as phthalic anhydride. Intermediates and final dispersant molecules were characterized by NMR, GPC, TGA, and MALDI‐TOF MS. Using Langmuir adsorption studies with carbon black as a surrogate for soot, a direct dependence on the affinity for adsorption of the dispersant with respect to the number of phenyl rings present was identified. Performance testing revealed increased compatibility of the dispersants, including limited degradation of seals and corrosion of metals, while retaining total base number. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1657–1675

Publication Title

Journal of Polymer Science Part A: Polymer Chemistry

Volume

56

Issue

15

First Page

1657

Last Page

1675

Link to Full Text

Share

COinS