Tire Tread Composition Using Thermoplastic Elastomer Block Copolymers
Solution Overview
Problem
Conventional tire treads face a performance trade-off between improving grip on wet surfaces and reducing rolling resistance, as enhancing grip increases hysteretic losses while reducing rolling resistance decreases grip, and maintaining good wear resistance is also a challenge.
Innovation Solution
A tire tread composition based on a thermoplastic elastomer block copolymer with a specific molecular weight range and glass transition temperature, combined with carbon black and a plasticizer, optimizing the balance between grip, rolling resistance, and wear resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the tread composition uses conventional diene elastomers and increases carbon black content to improve grip on wet surfaces, then grip performance is improved, but rolling resistance increases due to higher hysteretic losses
Solution Approach 1:
The patent changes the fundamental parameter of elastomer type from conventional diene elastomers to thermoplastic elastomers with specific glass transition temperatures. This parameter change allows the material to provide both high grip (through appropriate Tg selection for wet surface adhesion) and low rolling resistance (through reduced hysteresis of the thermoplastic elastomer structure), thereby resolving the contradiction between grip and energy loss
Solution Approach 2:
The patent employs composite material strategy by combining thermoplastic elastomer blocks with specific glass transition temperatures in a multi-block copolymer structure. This composite approach allows optimization of both grip (via Tg selection) and rolling resistance (via structural design), achieving performance that neither single elastomer type could provide alone
2Loss of energy
If the tread composition is optimized for low rolling resistance by reducing hysteretic losses, then rolling resistance is reduced, but grip performance deteriorates
Solution Approach 1:
The patent applies parameter changes by selecting thermoplastic elastomers with specifically controlled glass transition temperatures. This allows the material to exhibit low hysteresis (low rolling resistance) while maintaining adequate adhesion properties (grip performance) through the Tg selection, resolving the contradiction between energy efficiency and traction
3Duration of action of stationary object
If the tread uses high levels of carbon black to improve wear resistance, then wear resistance is improved, but the balance between grip and rolling resistance is compromised
Solution Approach 1:
The patent extracts the wear resistance function from the carbon black reinforcement role and assigns it to the thermoplastic elastomer matrix itself. By designing the TPE with appropriate block structures and glass transition temperatures, the material inherently provides both wear resistance and optimized grip/rolling resistance balance, reducing dependence on carbon black loading and thus resolving the performance balance contradiction
Data Source
AI summary
The present invention relates to a tire including a tread, a crown having a crown reinforcement, two sidewalls, two beads, a carcass reinforcement anchored to the two beads and extending from one sidewall to the other, characterized in that the tread contains at least one thermoplastic elastomer and a carbon black volume content of 5 to 30%, said thermoplastic elastomer being a block copolymer including at least one block elastomer and at least one thermoplastic block, and the total thermoplastic elastomer content being within the range of 65 to 100 pce (parts by weight per one hundred parts of elastomer).