Zieg-Natta Catalyst Oxalic Diamide Stereo-Specificity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current Ziegler-Natta catalyst systems for polypropylene production do not achieve sufficient isotacticity, particularly for highly crystalline propylene impact copolymers, necessitating a catalyst system with enhanced stereo-specificity.
Innovation Solution
A Ziegler-Natta catalyst system incorporating oxalic acid diamides and silane compounds, in combination with internal electron donors such as phthalate, diether, or malonate compounds, to improve the stereo-specificity of polypropylene production.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional Ziegler-Natta catalyst systems are used, then polypropylene can be produced, but the isotacticity and stereospecificity are insufficient
Solution Approach 1:
The patent employs a composite electron donor system combining oxalic acid diamide with traditional electron donors (phthalate, diether, or malonate compounds). This composite approach creates a synergistic effect where oxalic acid diamide enhances the stereospecificity and isotacticity of the catalyst system beyond what single donors can achieve, directly resolving the contradiction between manufacturing precision and reliability in polypropylene production
2Manufacturing precision
If electron donating compounds are incorporated to increase stereo-specificity, then isotacticity improves, but catalyst system complexity increases
Solution Approach 1:
The patent modifies the chemical composition parameter of the catalyst system by introducing oxalic acid diamide with specific molecular structure characteristics. This parameter change enhances the electron donation capability and stereospecificity of the catalyst without requiring complex structural modifications to the catalyst support or titanium compound, thus improving stereo-specificity while controlling system complexity
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 catalyst system achieves significantly higher isotacticity and stereospecificity in polypropylene production, as demonstrated by increased heptane insolubles and melt flow rate, while maintaining high activity and hydrogen response in both bulk and slurry polymerization processes.
Implementation Method 1
electron donating compounds have been incorporated into the Ziegler-Natta catalyst component during catalyst preparation, which is used as an internal electron donor
Implementation Method 2
Ziegler-Natta catalyst systems for polyolefin polymerization are well known in the art
Data Source
AI summary
Disclosed are a catalyst component for olefin polymerization comprising titanium, magnesium, a halogen, internal donors, in combination with a silane and oxalic acid diamides of the following formula:An olefin polymerization catalyst system consisting of the solid catalyst component, an organoaluminum compound, and an optional external electron donor compound is also disclosed. Employment of both oxalic acid diamides and silane component in the presence of internal electron donors as an elements of solid Ziegler-Natta type catalyst composition enhances stereo-specificity while maintaining excellent catalyst activity and hydrogen response, in which the modified catalyst composition produces polypropylene with good productivity and higher stereo-specificity than catalyst composition without such modification.