Functionalized Diene Elastomer Silane Coupling for Tire Tread Dispersion
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 to agglomerate, limiting dispersion and reinforcing properties, which complicates the reduction of rolling resistance and maintenance of wear resistance.
Innovation Solution
A rubber composition combining a high molecular weight diene elastomer with a functionalized low molecular weight diene elastomer containing alkoxysilyl groups, optionally hydrolyzed to silanol, and an amine function linked to the silicon atom, which improves the dispersion and incorporation of reinforcing inorganic fillers like silica, enhancing the material's mechanical and dynamic properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If inorganic fillers are used to reinforce tire tread, then wear resistance is improved, but filler agglomeration occurs limiting dispersion and reinforcing properties
Solution Approach 1:
The patent introduces a silane coupling agent as an intermediary substance that chemically bonds to both the inorganic filler particles and the elastomer matrix. This coupling agent has reactive groups that interact with the filler surface and compatible groups that integrate with the polymer, thereby preventing filler agglomeration and improving dispersion homogeneity while maintaining wear resistance enhancement.
Solution Approach 2:
The patent creates a composite material system consisting of elastomer, inorganic filler, and silane coupling agent. This composite structure allows the combination of materials with complementary properties, where the coupling agent acts as a bridge between the inorganic and organic phases, achieving both reinforcement and uniform distribution throughout the matrix.
2Strength
If high quantities of reinforcing filler are used, then reinforcement is improved, but rolling resistance increases
Solution Approach 1:
The silane coupling agent serves as a mediator that reduces the interfacial friction and energy dissipation between filler particles and the matrix. By improving the interfacial adhesion and reducing filler-agglomerate formation, the coupling agent allows high filler loads to be used without the proportional increase in rolling resistance that would otherwise occur.
Solution Approach 2:
The patent changes the chemical and physical parameters of the filler-matrix interface by introducing the coupling agent. This modifies the surface properties of the filler, changing the interaction mechanisms from physical adhesion to chemical bonding, thereby reducing energy loss through hysteresis and improving the reinforcement-to-rolling-resistance ratio.
3Strength
If inorganic fillers are incorporated into elastomer matrix, then reinforcing properties are improved, but filler agglomeration through strong interactions limits dispersion
Solution Approach 1:
The silane coupling agent acts as a molecular-level intermediary that interferes with the direct strong interactions between filler particles. By forming a chemical bridge, it prevents the fillers from aggregating through van der Waals forces or other strong interactions, thereby achieving uniform dispersion while maintaining the reinforcing network.
Solution Approach 2:
The coupling agent provides local quality improvement at the filler-matrix interface. Rather than uniformly modifying the entire system, it specifically targets the interfacial region where filler particles contact the matrix, creating localized zones of enhanced adhesion and controlled interaction that prevent agglomeration while preserving reinforcement.
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 achieves improved dispersion and reinforcing properties of silica, reducing material rigidity and rolling resistance while maintaining wear resistance, even at high filler loads, thus optimizing tire performance.
Implementation Method 1
comprising a blend of a functionalized low molecular weight diene elastomer comprising within its structure at least one alkoxysilyl group, optionally partially or totally hydrolyzed to silanol
Implementation Method 2
the alkoxysilyl group carrying an amine function linked to the silicon atom directly or via a spacer group
Implementation Method 3
the alkoxysilyl group carrying an amine function linked to the silicon atom directly or via a spacer group
Data Source
AI summary
The present invention relates to a rubber composition comprising at least: an elastomer matrix including (i) a first diene elastomer having a number average molecular weight, Mn, greater than or equal to 100000 g/mol, and (ii) a second functionalised diene elastomer comprising within its structure at least one alkoxy silyl group, optionally partially or fully hydrolysed to silanol, bound to the elastomer by means of the silicon atom, the alkoxy silyl group bearing an amine function bound to the silicon atom directly or via a spacer group, said functionalised diene elastomer having a number average molecular mass, Mn, less than or equal to 80000 g/mol; and an inorganic reinforcing filler. A good performance compromise can be obtained with the rubber composition of the invention, reducing hysteresis and reducing the stiffness of the composition even with a high content of inorganic reinforcing filler. The present invention also relates to a finished or semi-finished article comprising such a composition, a tyre tread comprising such a composition, a semi-finished product or tyre comprising such a composition.