Silica-Reinforced Diene Elastomer Composition for Low Rolling Resistance

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current diene rubber compositions reinforced with silica face challenges in achieving a balance between low rolling resistance and good wear resistance, as silica fillers tend to clump, limiting their dispersion and reinforcing properties compared to carbon black.

Innovation Solution

A rubber composition comprising a copolymer with ethylene units exceeding 50 mol% of its monomer units, a specific 1,3-dipolar compound, and a radical crosslinking system, along with predominantly silica as a filler, and a crosslinking system including (meth)acrylate compounds, is used to enhance dispersion and reinforcing properties.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If silica filler is used to reduce rolling resistance, then rolling resistance is improved, but wear resistance deteriorates due to poor dispersion

Engineering Contradiction:

Improverolling resistanceVSAvoidwear resistance

Core Design Contradiction:

Loss of energyVSStrength

Solution Approach 1:

The patent introduces silane coupling agents as intermediaries between silica filler particles and the rubber matrix. These coupling agents have dual functionality: one end bonds to silica surface hydroxyl groups while the other end interacts with rubber polymer chains, thereby improving interfacial adhesion and dispersion of silica without compromising wear resistance

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent modifies the surface chemistry parameters of silica filler through silane treatment, changing its surface energy and chemical reactivity. This parameter change enables better compatibility with the rubber matrix, improving dispersion quality while maintaining the low rolling resistance property of silica

Inventive Principle:

Principle #35Parameter changes

2Loss of energy

If silica filler is used to reduce rolling resistance, then rolling resistance is improved, but dispersion quality worsens due to agglomeration

Engineering Contradiction:

Improverolling resistanceVSAvoiddispersion homogeneity

Core Design Contradiction:

Loss of energyVSStability of the object's composition

Solution Approach 1:

Silane coupling agents serve as intermediary substances that prevent direct aggregation of silica particles by creating a molecular bridge to the rubber matrix, thereby maintaining homogeneous dispersion throughout the composite material

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent changes the surface energy parameters of silica through chemical modification with silanes, reducing particle-particle attraction and enhancing particle-matrix interaction, which prevents agglomeration and ensures uniform distribution

Inventive Principle:

Principle #35Parameter changes

3Strength

If carbon black is used to improve wear resistance, then wear resistance is improved, but rolling resistance worsens due to high hysteresis

Engineering Contradiction:

Improvewear resistanceVSAvoidrolling resistance

Core Design Contradiction:

StrengthVSLoss of energy

Solution Approach 1:

The patent creates a composite filler system combining silica and carbon black in specific ratios. This composite approach leverages the low rolling resistance of silica while using carbon black to provide wear resistance, achieving a balance that neither filler can achieve alone

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent adjusts the compositional parameters of the filler system by varying silica-to-carbon black ratios, optimizing the balance between rolling resistance and wear resistance based on specific application requirements

Inventive Principle:

Principle #35Parameter changes

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

This composition improves the performance compromise between wear resistance and rolling resistance, rivalling conventional carbon black reinforcement while maintaining lower hysteresis and improved processability.

Implementation Method 1

a crosslinking system comprising at least one radical polymerization initiator, and a co-crosslinking agent selected from the group consisting of (meth)acrylate compounds

Methodology Applied

Scientific EffectRadical polymerization: Photopolymerisation

Implementation Method 2

a 1,3-dipolar compound corresponding to the formula (I)

Methodology Applied

Scientific Effect1,3-dipolar interaction: Chemical Bonding

Implementation Method 3

to be incorporated in the matrix during the mixing with the elastomer and to deagglomerate and, on the other hand, to disperse homogeneously in this matrix

Methodology Applied

Scientific EffectDispersion: Dispersion (of waves)

Data Source

PatentUS20230391994A1Rubber composition based on a highly saturated diene elastomer

Publication Date: 2023.12.07 MICHELIN & CO (CIE GEN DES ESTAB MICHELIN)

AI summary

A rubber composition is based on at least: an elastomer matrix comprising more than 50 phr of a copolymer containing ethylene units and 1,3-diene units, the ethylene units in the copolymer representing more than 50 mol % of the monomer units of the copolymer; a specific 1,3-dipolar compound; a filler comprising predominantly silica and a crosslinking system comprising at least one radical polymerization initiator, and a co-crosslinking agent selected from the group consisting of (meth)acrylate compounds, maleimide compounds, allyl compounds, vinyl compounds and mixtures thereof.