Precipitated Silica Dispersion in Elastomers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current precipitated silica products have limitations in achieving a desirable blend of properties for effective dispersion and reinforcement in elastomer applications, requiring the development of silica with specific surface area, structure, and surface activity characteristics.
Innovation Solution
A precipitated silica with a BET/CTAB ratio of 0.8-1.35, DBP oil absorption of 240-320 ml/100 g, and CDBP coefficient of 0.4-0.9 is developed, which improves dispersibility in elastomer matrices through a synthesis process involving an aqueous solution of metal silicate, mineral acid, and a surfactant solution, allowing for optimal particle aggregation and surface modification.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If precipitated silica is used as reinforcing filler in elastomer, then reinforcement properties and stiffness are improved, but dispersibility in elastomer matrix deteriorates
Solution Approach 1:
The patent applies parameter changes by precisely controlling the BET/CTAB ratio (1.05-1.20), DBP absorption (260-300 ml/100g), and Sears number (20-30 ml/5g) of precipitated silica. These parameter optimizations balance the silica's surface area, pore structure, and surface activity, enabling both good dispersibility in elastomer and effective reinforcement properties.
Solution Approach 2:
The patent creates a composite effect by combining specific silica properties (controlled aggregation structure, optimized pore volume, and regulated surface chemistry) to achieve a filler material that simultaneously provides good dispersion and strong reinforcement in the elastomer matrix.
2Strength
If silica aggregate concentration is increased to improve reinforcement, then inter-particle interaction increases, but formation of bigger agglomerates occurs reducing dispersibility
Solution Approach 1:
The patent controls the structure parameter (DBP absorption) within 260-300 ml/100g and maintains BET/CTAB ratio between 1.05-1.20, which optimizes the aggregate concentration and prevents excessive agglomeration while maintaining reinforcement effectiveness.
3Strength
If high surface area silica is used to improve filler-elastomer interaction, then reinforcement is enhanced, but surface activity increases causing poor dispersibility
Solution Approach 1:
The patent optimizes surface activity by controlling the Sears number (20-30 ml/5g) and BET surface area (380-450 m²/g) parameters. This balanced approach ensures sufficient surface activity for good elastomer interaction while preventing excessive surface reactivity that would cause poor dispersibility.
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 developed silica exhibits enhanced dispersibility and reinforcement properties in elastomers, improving the durability and interaction between rubber and filler, leading to improved mechanical properties and performance in elastomer compositions.
Implementation Method 1
a precipitated silica having a BET/CTAB in a range of 0.8-1.35... improves dispersibility in elastomer matrices through a synthesis process involving an aqueous solution of metal silicate, mineral acid, and a surfactant solution, allowing for optimal particle aggregation and surface modification
Implementation Method 2
Silica synthesis process follows the condensation of primary particles into aggregates of typical dimensions of 100-200 nm, which are the real reinforcing species in rubber compounds
Data Source
AI summary
A precipitated silica is disclosed. Said precipitated silica has a BET/CTAB in a range of 0.8-1.35; a DBP oil absorption in a range of 240-320 ml/100 g; and a CDBP coefficient (DA) in range of 0.65 to 0.9. The precipitated silica has a micro pore area ranging from 6 to 35 m2/g and a micro pore volume ranging from 0.01 to 0.06 cm3/g.