Ester Polyol Esters for Lubricants via One-Step Excess Acid Synthesis

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current methods for producing ester polyol esters for lubricant applications face challenges such as high pour points and susceptibility to oxidation, particularly when using saturated fatty acids from tropical resources, which limits their performance and temperature range.

Innovation Solution

A one-step method using excess acid in the reaction mixture to esterify polyols with dicarboxylic and monocarboxylic acids, optimizing the hydroxyl to carboxyl group ratio and difunctional to monofunctional ratio to produce ester polyol esters with improved viscosity, pour point, and oxidative stability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If polyol esters are produced from saturated fatty acids derived from tropical resources, then the lubricant can be used in tropical climates, but the pour point becomes too high for use in lower temperature conditions

Engineering Contradiction:
Improvelubricant performance in tropical climateVSAvoidpour point
Core Design Contradiction:
ReliabilityVSTemperature

Solution Approach 1:

The patent applies parameter changes by modifying the chemical composition parameters of the ester polyol esters through controlled esterification reactions. By adjusting the ratio of polyol to acid components and controlling the degree of esterification, the patent produces esters with optimized molecular structures that have lower pour points while maintaining tropical climate performance. This involves changing parameters such as hydroxyl value, acid value, and molecular weight distribution to achieve the desired temperature range performance.

Inventive Principle:
Principle #35Parameter changes

2Adaptability or versatility

If double bonds are present in fatty acid components of polyol esters, then the structure is more flexible, but oxidation reactions occur at these double bonds leading to oil degradation

Engineering Contradiction:
Improvemolecular structure flexibilityVSAvoidoxidative stability
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The patent converts the harmful effect of double bonds (susceptibility to oxidation) into a benefit by using ozonolysis to cleave the double bonds and form carboxylic acid groups. This transformation eliminates the oxidation vulnerability while the resulting dicarboxylic and monocarboxylic acids provide structural flexibility when esterified with polyols. The harmful unsaturation is converted into useful functional groups that contribute to the desired molecular structure and performance characteristics.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

3Reliability

If a two-step synthesis method is used to produce ester polyol esters, then products of superior performance characteristics are obtained, but the reaction time is extended

Engineering Contradiction:
Improveperformance characteristicsVSAvoidreaction time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent merges the two-step synthesis method into a single-step process by combining the esterification of polyol with dicarboxylic acid and the subsequent esterification with monocarboxylic acid into one simultaneous reaction. This is achieved by adding both types of acids to the reaction mixture at the beginning and using excess acid to drive the reaction to completion. The merging eliminates the intermediate isolation step and reduces total reaction time while maintaining the performance benefits of having both diester and monoester groups in the final product.

Inventive Principle:
Principle #5Merging (Combining)

4Temperature

If fractionation is used to remove saturated components from ester mix, then the pour point is reduced, but the separation step does not adequately remove all saturates to meet stringent requirements

Engineering Contradiction:
Improvepour pointVSAvoidsaturate removal efficiency
Core Design Contradiction:
TemperatureVSManufacturing precision

Solution Approach 1:

The patent applies preliminary action by designing the esterification reaction to produce the desired molecular structure in advance, eliminating the need for subsequent fractionation. By using excess acid in the esterification reaction and controlling the reaction conditions, the patent directly produces ester polyol esters with the appropriate balance of saturated and unsaturated components, achieving the desired pour point without requiring post-reaction separation. This preliminary structuring of the molecules prevents the formation of excessive saturated components that would require removal.

Inventive Principle:
Principle #10Preliminary action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The one-step process significantly reduces reaction time while producing ester polyol esters with lower pour points and broader viscosity profiles, enhancing their applicability and thermal stability, potentially eliminating the need for pour point depressants and polymeric viscosity modifiers.

Implementation Method 1

oxidative ozonolysis of fatty acids

Methodology Applied
Scientific EffectOxidative ozonolysis: Ozone

Implementation Method 2

oxidative cleavage using ozone as the preferred cleavage reagent so that all double bonds are cleaved

Methodology Applied
Scientific EffectOxidation: Oxidation

Implementation Method 3

esterification reaction between ozone acids and at least one primary polyol

Methodology Applied
Scientific EffectEsterification: Chemical Bonding

Data Source

PatentEP2961729B1The preparation of biopolyol esters for lubricant application
Publication Date: 2019.06.26 PETROLIAM NASIONAL BHD
  • EP2961729B1 patent drawingFigure 1
  • EP2961729B1 patent drawingFigure 2
  • EP2961729B1 patent drawingFigure 3

AI summary

Ester polyol esters are a unique class of lubricants that have adjustable molecular weights, viscosities, and pour points based on the character of their reaction materials and relative ratios. There is provided a method for preparing at least one ester polyol ester, the method comprising the method comprising preparing a reaction mixture comprising at least one polyol compound; at least one dicarboxylic acid; and at least one monocarboxylic acid, wherein the at least one polyol compound is esterified with the at least one dicarboxylic acid and the at least one monocarboxylic acid, wherein the reaction mixture has a hydroxyl group to carboxyl group ratio (HCR) corresponding to a ratio of moles of hydroxyl groups to moles of carboxyl groups, and the HCR is less than about 1.