Rubber Compound Low-Temperature Flexibility

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing rubber mixtures for vehicle tires face a trade-off between low-temperature flexibility and static rigidity at high elongations, where improving one property often deteriorates the other, making it difficult to achieve both good winter properties and handling characteristics simultaneously.

Innovation Solution

A rubber compound composed of 30-100 phr of solid diene rubber, 5-50 phr of low-viscosity liquid rubber, 0.1-10 phr tetrabenzylthiuram disulfide, 0.1-150 phr amorphous or precipitated silica, 0-25 phr coupling agent, 1-100 phr carbon black, and 2-200 phr other additives, which enhances low-temperature flexibility while maintaining or improving static stiffness at high elongations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the degree of filling is increased or crosslinking density is increased to improve static rigidity, then the stiffness of the vulcanizate is improved, but the low-temperature flexibility deteriorates

Engineering Contradiction:
Improvestatic rigidityVSAvoidlow-temperature flexibility
Core Design Contradiction:
StrengthVSTemperature

Solution Approach 1:

The patent applies parameter changes by carefully controlling the crosslinking density within a specific range (0.5-5 mmol per 100g rubber) and optimizing the filler content (20-80 phr) to achieve a balance where static rigidity is improved while low-temperature flexibility is preserved. This resolves the contradiction by finding optimal parameter values that satisfy both requirements simultaneously.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent uses composite materials by combining rubber with specific fillers (such as silica or carbon black) and crosslinking agents to create a vulcanizate composition that achieves both high static rigidity and good low-temperature flexibility. The synergistic effect of the composite structure allows both properties to be improved rather than traded off against each other.

Inventive Principle:
Principle #40Composite materials

2Strength

If filler content is increased to improve handling and durability, then static rigidity is improved, but low-temperature flexibility deteriorates

Engineering Contradiction:
Improvehandling and durabilityVSAvoidlow-temperature flexibility
Core Design Contradiction:
StrengthVSTemperature

Solution Approach 1:

The patent optimizes the filler content parameter within the range of 20-80 phr (parts per hundred rubber) to achieve the desired balance. By controlling this parameter, the patent ensures that handling and durability are improved through adequate filler reinforcement while low-temperature flexibility is maintained by avoiding excessive filler loading that would overly stiffen the compound.

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 significantly improves winter properties and maintains or enhances static stiffness, decoupling the conflicting goals of low-temperature flexibility and static rigidity, applicable not only to tire treads but also to other tire components and belts.

Implementation Method 1

The vulcanization accelerators are used here to activate the sulfur used as a vulcanizing agent. The properties to be achieved are determined by the network created during vulcanization, e.g. between polymer and fillers.

Methodology Applied
Scientific EffectVulcanization: Chemical Bonding

Implementation Method 2

0.1-150 phr of at least one amorphous and/or precipitated silica; 0-25 phr of at least one coupling agent

Methodology Applied
Scientific EffectAdsorption: Adsorption

Data Source

PatentEP2082899B1Natural rubber mixture with improved low temperature flexibility
Publication Date: 2011.05.18 CONTINENTAL REIFEN DEUTSCHLAND GMBH

AI summary

Rubber mixture comprises at least a solid diene rubber (30-100 parts per hundred (phr)); at least a low viscous and liquid rubber; at least a thiuram catalyst (0.1-10); at least an amorphous and/or precipitated silicic acid (0-150 phr); at least a coupling agent (0-25 phr); at least a soot (1-100 phr); and a further additive (2-200 phr).