Lubricating Oil Defoaming Agent Composition for Shear Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional lubricating oils with silicone defoaming agents suffer from precipitation and concentration unevenness during storage and use, leading to reduced defoaming performance due to centrifugal effects and high shear stress, causing increased foaming and deterioration of lubricating properties.
Innovation Solution
A lubricating oil composition incorporating a first polymer with a polysiloxane structure and a second polymer, along with a silicone defoaming agent, which are finely dispersed to maintain stability and effectiveness under high centrifugal and shear conditions, using specific polymerization degrees and molecular weights to prevent segregation and precipitation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional silicone defoaming agent is incorporated into lubricating oil, then defoaming performance is improved, but the defoaming agent precipitates and concentrates unevenly during storage and use, leading to deterioration of defoaming performance over time
Solution Approach 1:
The invention uses a composite defoaming agent system comprising both a silicone defoaming agent and a fluorinated defoaming agent. The silicone defoaming agent (polydimethylsiloxane) provides primary defoaming performance, while the fluorinated defoaming agent (polyfluoroalkyl methacrylate) prevents precipitation and maintains uniform distribution. This composite approach leverages the complementary properties of both materials to achieve both high defoaming performance and long-term stability.
Solution Approach 2:
The fluorinated defoaming agent acts as an intermediary substance that prevents the silicone defoaming agent from precipitating and concentrating unevenly. The fluorinated compound maintains the uniform distribution of the silicone defoaming agent throughout the lubricating oil during storage and use, thereby preventing deterioration of defoaming performance over time.
2Force
If the lubricating oil is subjected to high centrifugal effect (e.g., in torque converters or CVT pulleys), then the silicone defoaming agent separates and concentrates in specific positions, but this leads to decreased defoaming agent concentration in circulating oil and increased foaming
Solution Approach 1:
The fluorinated defoaming agent serves as an intermediary that counteracts the centrifugal separation of the silicone defoaming agent. It maintains uniform distribution of the defoaming agent even under high centrifugal effects in torque converters and CVT pulleys, preventing concentration in specific positions and ensuring consistent defoaming performance throughout the circulating oil.
3Stress or pressure
If the lubricating oil undergoes high shear stress (e.g., in sliding parts or high-speed bearings), then the silicone defoaming agent molecules are cut and molecular weight decreases, but this results in deteriorated defoaming performance in the endurance stage
Solution Approach 1:
The fluorinated defoaming agent acts as a protective intermediary that prevents the degradation of the silicone defoaming agent under high shear stress conditions. It maintains the molecular integrity and effectiveness of the silicone defoaming agent even in high-stress environments like sliding parts and high-speed bearings, ensuring sustained defoaming performance throughout the lubricating oil's service life.
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 composition effectively suppresses defoaming performance deterioration, maintaining long-term effectiveness and preventing foaming issues even under high stress conditions, ensuring consistent lubrication and hydraulic pressure control.
Implementation Method 1
Molecules of the silicone defoaming agent compound incorporated in the lubricating oil as a defoaming agent are cut due to high shear stress
Implementation Method 2
the silicone defoaming agent compound used as a defoaming agent is separated by such centrifugal effect, and concentrates in a specific position of the machinery
Implementation Method 3
a lubricating oil composition formed by incorporating (a) polydimethylsiloxane having a kinematic viscosity at 25° C. of 300,000 to 1,500,000 mm2/s, and (b) fluorinated polysiloxane having a kinematic viscosity at 25° C. of 500 to 9,000 mm2/s
Data Source
AI summary
A lubricating oil composition including: a lubricating base oil; (A) a first defoaming agent, the first defoaming agent being (A1) a first polymer, or (A2) a second polymer, or any combination thereof; and (B) a second defoaming agent, the second defoaming agent being a silicone defoaming agent, the (A1) first polymer including: a first polymer chain including a polysiloxane structure, the polysiloxane structure having a polymerization degree of 5 to 2000 and being represented by the following general formula (1); and a second polymer chain bonded with the first polymer chain, the second polymer chain including a repeating unit represented by the following general formula (2), the (A2) second polymer being a copolymer of a first monomer component and a second monomer component, the first monomer component represented by the general formula (7) or (8), the second monomer component represented by the general formula (9).