Borate Ester Functional Fluid for High Boiling, Low Precipitation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing brake fluids with high borate ester content face issues of borate precipitation and adverse lubrication and noise behavior, failing to meet high wet boiling points and other performance criteria.
Innovation Solution
A functional fluid composition comprising alkoxyglycol borate esters, alkoxyglycol ethers, and cycloalkylamine alkoxylates, with specific ethoxylation and propoxylation ratios, along with additives for corrosion inhibition, stability, and lubrication, achieving high wet and dry boiling points and low noise.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If high weight percent of borate ester is used to meet DOT 4 and DOT 5.1 criteria with very high wet boiling point, then wet equilibrium reflux boiling point is improved, but tendency for gel formation or precipitation increases due to salt formation of inorganic boron salts
Solution Approach 1:
Cycloalkylamine alkoxylates act as intermediary substances that complex with boron salts, preventing direct salt formation and precipitation. The additive package containing cycloalkylamine alkoxylates serves as a mediator between the borate ester component and the aqueous environment, maintaining solubility and preventing gel formation while preserving the high wet boiling point property
Solution Approach 2:
The invention changes the chemical parameters of the system by introducing specific additives (cycloalkylamine alkoxylates with specific molecular weights and structures) that alter the solubility characteristics of boron salts. This parameter change allows the system to maintain high borate ester content for high wet boiling point while preventing precipitation through modified chemical interactions
2Reliability
If conventional additives are used in brake fluids with high borate ester content, then corrosion resistance is improved, but noise behavior deteriorates due to poor lubrication properties
Solution Approach 1:
The additive package employs a composite formulation combining cycloalkylamine alkoxylates with specific molecular weights and structures that provide both corrosion inhibition and superior lubrication properties. This composite approach allows simultaneous achievement of corrosion resistance and noise reduction, overcoming the limitation of conventional single-function additives
Solution Approach 2:
The cycloalkylamine alkoxylates serve multiple functions simultaneously: they provide corrosion resistance, improve lubrication properties for noise reduction, and maintain stability with high borate ester content. This multi-functionality resolves the contradiction by eliminating the need to trade off between corrosion protection and noise performance
3Temperature
If low-molecular-weight secondary amines are used with high proportion of borate ester, then wet boiling point is improved, but precipitation tendency increases as demonstrated in THF precipitation test
Solution Approach 1:
The invention fundamentally changes the molecular weight parameter and chemical structure of the amine component by using cycloalkylamine alkoxylates with higher molecular weights and specific cyclic structures. This parameter change transforms the system from one prone to precipitation with low-molecular-weight amines to one with high stability, while maintaining the high wet boiling point through the borate ester-cycloalkylamine complex
Data Source
AI summary
The invention relates to a functional fluid composition comprising (A) 74 - 94 wt.% of an alkoxyglycol borate ester of the formula (I) [R1-O-(CH2CH2-O)n]3B (I) wherein R1 represents a C1- to C4-alkyl group or a mixture of such alkyl groups, and n has a value of 2 to 6, (B) from 3 to 23 wt.% of an alkoxyglycol ether of the formula (II) R2-O-(CH2CH2O)mH (II) wherein R2 represents H, a C1- to C4-alkyl radical or a mixture of such alkyl radicals, and m is a number from 2 to 6, (C) from 2 to 5 wt.% of a cycloalkylamine alkoxylate of the formula (III) wherein R3 represents a cycloalkyl radical having 5 to 7 carbon atoms, R is a methyl group or H, and p and q independently of one another represent a number between 1 and 15, (D) at least one additive selected from the group consisting of corrosion inhibitors, alkalinity agents, stabilizers, defoamers, dyes and lubricants.