Elastomer Masterbatch Silica Dispersion Process
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing rubber compositions face challenges in achieving optimal reinforcement and hysteresis properties for tire treads due to the tendency of inorganic fillers like silica to agglomerate, limiting dispersion and processability, especially when compared to carbon black, which affects wear resistance and rolling resistance.
Innovation Solution
A rubber composition based on a diene elastomer with a masterbatch containing carbon black and silica, where the silica is incorporated along with a second elastomer, improving dispersion and maintaining good filler distribution in the elastomeric matrix, achieved by a process involving coagulation and drying in a coagulation reactor.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If inorganic filler (silica) is used to reduce rolling resistance and improve hysteresis, then fuel efficiency and environmental performance are improved, but the filler tends to agglomerate which limits dispersion and increases consistency
Solution Approach 1:
The patent applies preliminary action by pre-dispersing silica filler in water to create an aqueous dispersion before incorporating it into the elastomer matrix. This pre-dispersion step prevents agglomeration during subsequent mixing operations, ensuring uniform distribution of silica particles throughout the rubber composition while maintaining the desired reduction in rolling resistance and hysteresis.
2Reliability
If inorganic filler (silica) is used to improve hysteresis properties, then wear resistance and grip are improved, but the consistency of the rubber composition increases making processing more difficult
Solution Approach 1:
The patent uses water as an intermediary medium to disperse silica filler. By first creating an aqueous dispersion of silica and then incorporating this dispersion into the elastomer, the water acts as a mediator that facilitates uniform distribution of silica particles without causing excessive agglomeration. This approach maintains good processability while achieving the desired wear resistance and hysteresis properties.
3Stability of the object's composition
If carbon black is used as filler, then good dispersion and reinforcement are achieved, but hysteresis and rolling resistance are higher compared to inorganic fillers
Solution Approach 1:
The patent applies parameter changes by transitioning from using carbon black (organic filler) to using silica (inorganic filler) as the reinforcing filler. This fundamental change in filler type alters the hysteresis characteristics of the rubber composition, reducing energy loss and rolling resistance while maintaining adequate dispersion through the aqueous dispersion method. The parameter change from carbon black to silica directly addresses the hysteresis issue while the dispersion technique maintains compositional stability.
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 solution enhances hysteresis properties and maintains good dispersion of fillers, leading to improved wear resistance and reduced rolling resistance without compromising the reinforcement, thus addressing the limitations of using silica in rubber compositions.
Implementation Method 1
the mixing of these two fluids being sufficiently energetic to allow the elastomer latex to coagulate almost completely with the filler before the outlet of the coagulation reactor
Implementation Method 2
and then to dry the coagulum obtained
Data Source
AI summary
The invention relates to a rubber composition based on at least one diene elastomer, a reinforcing filler comprising at least carbon black and an inorganic filler with an amount of inorganic filler of less than or equal to 50 parts by weight per hundred parts of elastomer, characterized in that the composition is obtained from a first masterbatch comprising at least one first diene elastomer and carbon black, and exhibiting a dispersion of the carbon black in the elastomeric matrix having a Z score greater than or equal to 90, to which the inorganic filler and at least one second elastomer, identical to or different from the first elastomer, is added, and also to the process for preparing such a composition.