Pneumatic Tire Silica Rubber Composition Heat Build-Up
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing tire technologies face challenges in achieving low heat build-up and abrasion resistance simultaneously, with silica fillers often resulting in poor dispersion and processability issues due to hydrogen bonding and hydrophilicity, and carbon black reducing reinforcing properties when used alone.
Innovation Solution
A rubber composition combining low molecular weight aromatic vinyl compound-diene copolymer with structural precipitated silica and a silane coupling agent, along with carbon black, to enhance compatibility and reinforcing properties, while controlling particle size and surface area for improved processability and heat management.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If silica is used as a filler to reduce heat build-up, then low heat build-up is improved, but dispersion and processability deteriorate due to hydrogen bonding and hydrophilicity
Solution Approach 1:
A silane coupling agent is introduced as an intermediary substance between silica particles and rubber molecules. The silane coupling agent has affinity for both silica (through silanol groups) and rubber (through organic functional groups), acting as a bridge that improves interfacial adhesion and dispersion without compromising the low heat build-up properties of silica
Solution Approach 2:
The surface properties of silica are modified by controlling the hydrophobicity treatment to maintain appropriate surface characteristics. The silane coupling agent changes the surface chemistry of silica, reducing excessive hydrophilicity while preserving the low heat build-up mechanism through controlled parameter modification
2Strength
If carbon black is used as a reinforcing filler to improve abrasion resistance, then abrasion resistance is improved, but reinforcing property and grip on wet road are reduced when compounding amount is reduced or particle diameter is increased
Solution Approach 1:
The invention uses a composite filler system combining silica and carbon black in specific ratios. This composite approach leverages the low heat build-up properties of silica while incorporating enough carbon black to maintain adequate abrasion resistance and wet grip, achieving a balanced performance through material composition
3Temperature
If precipitated silica is used to enhance low heat build-up, then low heat build-up is improved, but dispersion into rubber is inferior due to surface aggregation
Solution Approach 1:
The silane coupling agent serves as a mediating substance that prevents silica particle aggregation by forming a protective interface layer. This intermediary reduces the tendency of silica particles to aggregate through hydrogen bonding while maintaining their dispersibility in the rubber matrix
Solution Approach 2:
The harmful effect of surface silanol groups is extracted or neutralized by reacting them with the silane coupling agent. This removes the excessive hydrophilicity and aggregation tendency while preserving the core low heat build-up mechanism of silica
4Stability of the object's composition
If silica surface is treated with hydrophobicity-providing agent to improve dispersion, then dispersion is improved, but surface silanol groups disappear and reinforcing property is reduced
Solution Approach 1:
The hydrophobicity of silica surface is controlled at an optimal level rather than completely eliminated. The silane coupling agent provides moderate hydrophobicity improvement for better dispersion while preserving enough silanol groups to maintain reinforcing interactions with rubber molecules
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 achieves a balance between low heat build-up and abrasion resistance, improving tire performance and reducing fuel consumption, thereby contributing to energy saving.
Implementation Method 1
A silane coupling agent having a specific structure is used in combination with the low molecular aromatic vinyl compound-diene compound copolymer and the structural precipitated silica
Implementation Method 2
a silane coupling agent having a specific structure is used in combination with the low molecular aromatic vinyl compound-diene compound copolymer and the structural precipitated silica
Data Source
AI summary
A pneumatic tire prepared by using a rubber composition prepared by compounding precipitated silica with a rubber component comprising 100 parts by mass of a rubber component (A) comprising at least one of a natural rubber and a synthetic diene base rubber and 5 to 60 parts by mass of an aromatic vinyl compound-diene compound copolymer (B) having a weight average molecular weight of 4,000 to 250,000 which comprises 0 to 80 % by mass of the aromatic vinyl compound and in which a vinyl bond content in the parts of the diene compound is 0 to 80 % by mass, wherein a cetyltrimethylammonium bromide-adsorbing specific surface area (CTAB) (m2/g) of the precipitated silica and the mode Aac (nm) in diameters of primary aggregates thereof determined by acoustic measurement of particle size distribution satisfy equation (I) shown below: Aac≧-0.76×CTAB+274 and an ignition loss (mass reduction % when heated at 750°C for 3 hours) of the precipitated silica and a heating loss (mass reduction % when heated at 105°C for 2 hours) thereof further satisfy an equation ignition loss-heating loss≦3