Bis-phenoxy-ether Ligands for High-Temperature Olefin Polymerization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current catalyst systems for olefin polymerization struggle to efficiently produce polymers with high molecular weights and narrow molecular weight distributions, particularly at high temperatures and pressures.
Innovation Solution
The development of a catalyst system comprising metal-ligand complexes, specifically those with a metal center of titanium, zirconium, or hafnium, and ligands such as bis-phenoxy-ether ligands, which form complexes with 6 or fewer metal-ligand bonds, enhancing polymerization efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional catalyst systems are used for olefin polymerization, then polymerization can proceed under standard conditions, but the efficiency is insufficient to produce high molecular weight polymers with narrow molecular weight distributions at high temperatures
Solution Approach 1:
The patent employs parameter changes by modifying the ligand structure (using bis-phenoxy-ether ligands with specific R1-R6 substituents) and metal center composition (titanium, zirconium, or hafnium) to achieve high polymerization efficiency at elevated temperatures (≥150°C), transforming the catalyst's chemical parameters to maintain activity under harsher conditions
Solution Approach 2:
The catalyst system uses composite material principles by combining metal centers (Ti, Zr, or Hf) with specifically designed bis-phenoxy-ether ligand structures, creating a composite catalyst complex that exhibits enhanced thermal stability and activity, allowing efficient polymerization at high temperatures while producing high molecular weight polymers
2Manufacturing precision
If conventional catalyst systems are used, then polymerization can occur, but the molecular weight distribution of the produced polymer is broad rather than narrow
Solution Approach 1:
The patent applies local quality principles through the specific ligand structure design where different substituents (R1-R6) at various positions on the bis-phenoxy-ether ligand create localized electronic and steric environments that control monomer insertion rates, resulting in narrow molecular weight distributions while maintaining high overall polymerization efficiency
Solution Approach 2:
The catalyst system exhibits dynamic behavior through the labile ligand exchange capability and flexible coordination sphere of the metal center with the bis-phenoxy-ether ligand, allowing the catalyst to adapt its structure during polymerization to maintain consistent activity and produce polymers with narrow molecular weight distributions across different conversion levels
3Stability of the object's composition
If the number of metal-ligand bonds is increased to enhance stability, then complex stability improves, but polymerization efficiency decreases due to excessive coordination
Solution Approach 1:
The patent applies partial action by forming metal-ligand complexes with 6 or fewer bonds, using just enough coordination to stabilize the complex while leaving sufficient coordination sites open for substrate binding and catalytic activity, avoiding excessive coordination that would deactivate the catalyst
Solution Approach 2:
The bis-phenoxy-ether ligand structure serves multiple functions simultaneously: it provides thermal stability through strong metal-ligand bonding, maintains appropriate coordination geometry, and allows necessary ligand exchange for substrate binding, achieving both stability and high polymerization efficiency through multi-functional design
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 catalyst system achieves high efficiency in polymerizing ethylene and alpha-olefins, producing polymers with high molecular weights and narrow molecular weight distributions, even at elevated temperatures and pressures.
Implementation Method 1
catalyst system comprising one or more metal-ligand complexes according to formula (I)... polymerizing ethylene and alpha-olefins that operate at high efficiencies... producing polymers with high molecular weights
Data Source
AI summary
Catalyst systems comprising one or more metal-ligand complexes according to formula (I).