Tire Sidewall Elastomeric Composition for Crack Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional metallic protective plies for tyre sidewalls are expensive, heavy, and have reduced manufacturing rates due to high twist requirements, making them unsuitable for passenger vehicles, and they also have suboptimal resistance to cracking and external attacks.
Innovation Solution
A tyre external sidewall composition featuring an elastomeric matrix with diene elastomers, thermoplastic elastomers without polyisobutylene blocks, a liquid plasticizer with a glass transition temperature below -70°C, and a reinforcing filler, which enhances resistance to external attacks and reduces weight and manufacturing costs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If metallic protective plies are used in tyre sidewalls, then resistance to external attacks is improved, but weight increases
Solution Approach 1:
The patent changes the material parameters by using elastomeric compositions with specific glass transition temperatures (≤-50°C for diene elastomers, ≤-60°C for protective plies) and specific plasticizer content (5-30 phr), transforming the sidewall material from conventional rubber to a specialized elastomeric composite that achieves protective performance without metallic reinforcement
Solution Approach 2:
The patent creates a composite elastomeric material combining diene elastomers, protective plies with different Tg characteristics, liquid plasticizers, and reinforcing fillers to achieve both flexibility and resistance to external attacks, replacing the need for metallic protective plies
2Strength
If metallic protective plies with high twist are used, then elasticity and resistance to external attacks are improved, but manufacturing rate decreases
Solution Approach 1:
The patent extracts the protective function from the metallic cord structure and transfers it to the elastomeric composition itself through careful selection of materials with appropriate glass transition temperatures and plasticizer content, eliminating the need for complex metallic strand twisting processes
Solution Approach 2:
The patent replaces the mechanical metallic cord reinforcement system with a chemically formulated elastomeric system where the protective properties arise from the molecular characteristics of the elastomer and plasticizer rather than from physical metallic structures
3Ease of manufacture
If conventional rubber compositions are used in sidewalls, then ease of manufacture is maintained, but resistance to cracking is insufficient
Solution Approach 1:
The patent modifies the chemical parameters of the rubber composition by specifying diene elastomers with glass transition temperatures ≤-50°C and incorporating liquid plasticizers at 5-30 phr levels, which fundamentally changes the material's resistance to cracking while maintaining compatibility with conventional manufacturing processes
Solution Approach 2:
The patent applies different functional characteristics to different components of the sidewall composition: the diene elastomer provides base flexibility, the protective plies with specific Tg provide crack resistance, and the liquid plasticizer enhances overall durability, creating a multi-functional composite material
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 improved resistance to external attacks, reduced weight, and lower production costs, while maintaining flexibility and comfort, making it suitable for passenger vehicles.
Implementation Method 1
a liquid plasticizer exhibiting a glass transition temperature of less than −70° C.
Implementation Method 2
an elastomeric matrix comprising at least one diene elastomer selected from the group consisting of butadiene polymers having a glass transition temperature of less than or equal to −50° C.
Implementation Method 3
a crosslinking system
Data Source
AI summary
A tire is provided with an external sidewall, said external sidewall comprising a composition based on at least one elastomeric matrix comprising at least one diene elastomer selected from the group consisting of butadiene polymers having a glass transition temperature of less than or equal to −50° C., and a thermoplastic elastomer comprising at least one elastomer block and at least one thermoplastic block, the thermoplastic elastomer not comprising a polyisobutylene block; a liquid plasticizer exhibiting a glass transition temperature of less than −70° C.; a crosslinking system; and a reinforcing filler.