Rubber Composition for Tire Treads with Low-Tg Plasticizer

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Snow tires face a trade-off in grip performance, where improved wet braking capability often compromises snow traction, and existing solutions fail to enhance wet grip without degrading snow performance.

Innovation Solution

A novel rubber composition for tire treads incorporating a reinforcing filler, a liquid plasticizer with a low glass transition temperature, and a crosslinking system, along with an elastomer matrix containing at least 20 mol% of a specific methacrylic acid ester, which enhances wet grip without compromising snow traction.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If snow tires use rubber compositions with low glass transition temperature to improve snow grip, then snow traction is improved, but wet ground grip performance deteriorates

Engineering Contradiction:
Improvesnow gripVSAvoidwet ground grip
Core Design Contradiction:
ReliabilityVSReliability

Solution Approach 1:

The patent applies parameter changes by carefully controlling the glass transition temperature of the rubber composition to be between -60°C and -100°C, and by specifying precise compositional parameters including at least 20 mol% methacrylic acid ester units and 5-20 phr liquid plasticizer. These parameter optimizations enable the rubber to maintain appropriate flexibility on snow while providing sufficient grip on wet ground, thus resolving the contradiction between snow and wet ground performance

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent employs composite materials by combining multiple rubber components including diene rubber, polyene rubber, and specifically methacrylic acid ester-containing elastomers in a formulated composition. This composite approach allows the tire tread to exhibit dual characteristics: low-temperature flexibility for snow grip and adequate adhesion for wet ground performance, thereby resolving the performance trade-off

Inventive Principle:
Principle #40Composite materials

2Reliability

If snow tires use rubber compositions with higher glass transition temperature to improve wet ground grip, then wet ground grip is improved, but snow traction deteriorates

Engineering Contradiction:
Improvewet ground gripVSAvoidsnow grip
Core Design Contradiction:
ReliabilityVSReliability

Solution Approach 1:

The patent resolves this contradiction by precisely controlling the glass transition temperature parameter within the optimal range of -60°C to -100°C, avoiding both extremes. Additionally, the patent specifies quantitative compositional parameters including 20-40 phr diene rubber, 10-30 phr polyene rubber, and 5-20 phr liquid plasticizer, which collectively optimize the rubber's performance across both wet and snowy conditions

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

The rubber composition significantly improves wet grip performance while maintaining or even enhancing snow traction, as demonstrated by higher friction coefficients on both wet and snowy surfaces compared to conventional snow tires.

Implementation Method 1

more than 35 phr of a liquid plasticizer exhibiting a Tg of less than -65°C

Methodology Applied
Scientific EffectGlass transition:

Implementation Method 2

a crosslinking system; an elastomer matrix reactive to the crosslinking system

Methodology Applied
Scientific EffectCrosslinking: Chemical Bonding

Implementation Method 3

a low friction coefficient, which leads to the development of snow tires

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP3303428B1A rubber composition
Publication Date: 2020.02.19 MICHELIN & CO (CIE GEN DES ESTAB MICHELIN)

AI summary

The present invention relates to a rubber composition based on a reinforcing filler, on more than 35 phr of a liquid plasticizer exhibiting a Tg of less than -65°C, on an elastomer matrix that is reactive to the crosslinking system, which elastomer matrix comprises an elastomer A comprising monomer units of a first methacrylic acid ester which represent at least 20 mol% of the monomer units of the elastomer A, and on a crosslinking system. The rubber composition makes it possible to improve the wet grip of tires whose tread consists of the rubber composition, without degrading, or even while improving, the snow grip of tires.