Tire Tread Thermoplastic Elastomer Rolling Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional tires face a compromise between reducing rolling resistance and maintaining wet grip, with existing thermoplastic elastomer treads not achieving sufficient reductions in rolling resistance.
Innovation Solution
A tire tread comprising a block copolymer thermoplastic elastomer with a butadiene/styrene random copolymer elastomer block and a styrene thermoplastic block, with a specific molecular weight range and glass transition temperature configuration, along with optional polyphenylene ether units, to achieve enhanced rolling resistance reduction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If conventional diene elastomers are used in the tread, then wet grip is maintained, but rolling resistance cannot be sufficiently reduced
Solution Approach 1:
The patent changes the chemical composition parameters of the elastomer by using a specific block copolymer structure with styrene and butadiene blocks in defined ratios (styrene content 10-60%, butadiene content 40-90%). This parameter change enables simultaneous achievement of low rolling resistance and adequate wet grip, resolving the contradiction between energy loss and reliability.
Solution Approach 2:
The patent employs a composite block copolymer material combining styrene blocks (thermoplastic, crystalline) and butadiene blocks (elastomeric, amorphous) in a specific architecture. This composite structure at the molecular level allows the material to exhibit both low hysteresis (reducing rolling resistance) and sufficient adhesion (maintaining wet grip), thus resolving the technical contradiction.
2Loss of energy
If existing thermoplastic elastomer treads are used, then rolling resistance is reduced, but the reduction is not sufficient compared to conventional treads
Solution Approach 1:
The patent optimizes specific parameters of the thermoplastic elastomer including the styrene content (10-60%), butadiene content (40-90%), molecular weight (30,000-500,000 g/mol), and block copolymer architecture. These parameter changes achieve a rolling resistance reduction that is significantly greater than conventional thermoplastic elastomer treads, thereby improving productivity/performance efficiency.
3Strength
If the thermoplastic elastomer has high molecular weight, then mechanical strength is improved, but processing difficulty increases
Solution Approach 1:
The patent specifies an optimized molecular weight range of 30,000-500,000 g/mol for the block copolymer. This parameter change balances the contradiction between mechanical strength (which improves with higher molecular weight) and processing ease (which improves with lower molecular weight), enabling both adequate strength and manufacturability.
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 provides a significant reduction in rolling resistance compared to conventional and existing thermoplastic elastomer treads, while maintaining performance across various vehicle types and conditions.
Implementation Method 1
the elastomer block(s) of the block copolymer are chosen from elastomers having a glass transition temperature of less than 25° C.
Implementation Method 2
the thermoplastic styrene block(s) of the block copolymer are chosen from polymers having a glass transition temperature of greater than 80° C.
Data Source
AI summary
The present invention relates to a tire comprising a tread, a crown with a crown reinforcement, two sidewalls, two beads, a carcass reinforcement anchored to the two beads and extending from one sidewall to the other, in which the tread comprises at least one thermoplastic elastomer, said thermoplastic elastomer being a block copolymer comprising at least one elastomer block of optionally hydrogenated butadiene/styrene random copolymer type and at least one thermoplastic block of styrene type, and the total content of thermoplastic elastomer being within a range varying from 65 to 100 phr (parts by weight per hundred parts of elastomer).