Modified Conjugated Diene Polymer Branching Control

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional methods for modifying conjugated diene-based polymers to improve their physical properties and processability face challenges in controlling the degree of branching and Mooney viscosity, leading to unstable modification processes and insufficient reproducibility.

Innovation Solution

A method involving the polymerization of conjugated diene-based monomers using a rare earth metal catalyst composition, followed by the addition of a specific compound represented by Formula 1 and sulfur chloride, which controls the modification reaction rate and reproducibility, thereby achieving stable and reproducible physical property changes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Shape

If sulfur chloride is added as a modifier to introduce branch structure, then the linearity of polymer decreases and Mooney viscosity increases, but the reaction rate becomes difficult to control due to aluminum component in catalyst system, leading to unstable modification process

Engineering Contradiction:

Improvelinearity of polymerVSAvoidstability of modification process

Core Design Contradiction:

ShapeVSStability of the object's composition

Solution Approach 1:

A rare earth metal catalyst composition is introduced as an intermediary between the sulfur chloride modifier and the conjugated diene-based polymer. This catalyst system mediates the modification reaction, enabling controlled introduction of branch structures while maintaining stable and reproducible modification processes, overcoming the uncontrollable reaction rate caused by aluminum components in conventional catalyst systems

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The invention changes the catalyst system parameters from conventional aluminum-based catalysts to a specific rare earth metal catalyst composition. This parameter change allows precise control over the modification reaction rate, enabling stable control of degree of branching and Mooney viscosity increase while maintaining process stability and reproducibility

Inventive Principle:

Principle #35Parameter changes

2Adaptability or versatility

If conventional modification methods are used to improve physical properties, then dispersibility of inorganic filler is increased, but the improving effects on abrasion resistance and processability are insufficient

Engineering Contradiction:

Improvedispersibility of inorganic fillerVSAvoidabrasion resistance

Core Design Contradiction:

Adaptability or versatilityVSStrength

Solution Approach 1:

The invention creates a composite modified polymer structure by introducing branch structures through controlled modification with sulfur chloride using rare earth metal catalysts. This composite approach combines the benefits of improved inorganic filler dispersibility with enhanced mechanical properties including abrasion resistance and processability, achieving synergistic effects that conventional single-method modifications cannot accomplish

Inventive Principle:

Principle #40Composite materials

3Ease of manufacture

If degree of branching is controlled by conventional modifiers, then Mooney viscosity increases, but control of overall modification reaction rate becomes difficult, making stable modification process unachievable

Engineering Contradiction:

ImproveMooney viscosity controlVSAvoidmodification reaction rate control

Core Design Contradiction:

Ease of manufactureVSProductivity

Solution Approach 1:

The rare earth metal catalyst composition provides feedback control mechanisms for the modification reaction. The catalyst system responds to reaction conditions and adjusts the modification rate accordingly, enabling precise control of both Mooney viscosity increase and degree of branching while maintaining stable and reproducible modification processes throughout production

Inventive Principle:

Principle #23Feedback

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 approach allows for precise control of the physical properties of the modified conjugated diene-based polymer, enhancing its tensile strength, viscoelasticity, and processability while maintaining consistent Mooney viscosity increases, thus improving compounding properties and modification reproducibility.

Implementation Method 1

a step of polymerizing a conjugated diene-based monomer in the presence of a rare earth metal catalyst composition to prepare an active polymer

Methodology Applied

Scientific EffectCatalysis: Catalysis

Implementation Method 2

a step of adding an additive including compound (1) and sulfur chloride to perform modification

Methodology Applied

Scientific EffectChemical reaction: Chemical Bonding

Data Source

PatentUS11713365B2Method for preparing modified conjugated diene-based polymer

Publication Date: 2023.08.01 LG CHEM LTD

AI summary

A method for preparing a modified conjugated diene-based polymer is provided. The method is characterized in adding a polyoxyethylene phosphate ester-based compound having a specific structure together with sulfur chloride modifier during modification, by which modification reproducibility may be markedly improved, stable process may be performed, the changing degree of the physical properties, specifically a Mooney viscosity increasing ratio and the degree of branching of a modified conjugated diene-based polymer according to modification conditions may be anticipated, and the changing degree of a Mooney viscosity increasing ratio and the degree of branching may be easily controlled by controlling modification conditions.