Functionalized Elastomer Synthesis via Neodymium Catalyst
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for producing stereoregular polymers with polar functional groups are limited due to catalyst sensitivity towards heteroatom-containing substrates, and existing techniques for stereoregular poly(dienes) do not provide access to polymers with functional groups in the main chain and end-groups simultaneously.
Innovation Solution
The use of polar functionalized organo-metal activators in combination with neodymium-based catalysts, such as Nd(BH4)3.(THF)3, allows for the synthesis of chain-end functionalized stereoregular dienes through direct copolymerization with functionalized dienes, enabling the introduction of functional groups into the polymer backbone and chain-ends, including hetero-telechelic and in-chain functionalization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional catalysts are used for stereoregular polymerization, then stereoregularity is achieved, but the catalyst is sensitive towards heteroatom-containing substrates and cannot incorporate polar functional groups
Solution Approach 1:
The patent employs a two-component catalyst system where a lanthanide complex serves as the primary catalyst and an organometallic compound acts as an activator/mediator. This intermediary component enables the catalyst to tolerate and incorporate heteroatom-containing functional groups while maintaining stereoregular polymerization, resolving the contradiction between catalyst sensitivity and functional group incorporation capability
Solution Approach 2:
The invention creates a composite catalyst system combining lanthanide complexes with organometallic activators. This composite approach integrates the stereoselectivity of the lanthanide catalyst with the functional group tolerance and activation capabilities of the organometallic component, enabling simultaneous achievement of stereoregularity and polar functional group incorporation
2Ease of manufacture
If existing polymerization methods are used for poly(dienes), then polymerization occurs, but functional groups cannot be introduced simultaneously in the main chain and end-groups
Solution Approach 1:
The patent applies local quality by introducing different functional groups at different locations of the polymer chain. The organometallic activator imparts specific functionality at the chain end, while the catalyst system simultaneously enables incorporation of functional groups within the main chain through copolymerization, achieving site-specific functionalization with different chemical characteristics at different positions
Solution Approach 2:
The organometallic compound performs preliminary action by activating the lanthanide catalyst and simultaneously introducing the initial functional group at the chain end before polymerization begins. This pre-functionalization step ensures that functional groups are present at both chain ends and enables subsequent incorporation of additional functional groups in the main chain
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 enables the production of stereoregular poly(dienes) with functional groups at both chain ends and in the main chain, maintaining stereoregularity and allowing for high-cis or high-trans polymers, thus overcoming the limitations of previous methods.
Implementation Method 1
polymerizing a conjugated diene monomer in the presence of a lathanide-based coordination polymerization catalyst
Implementation Method 2
activated with a magnesium compound of formula (I)
Data Source
AI summary
The present invention is directed to a method of making a functionalized elastomer, comprising the step of polymerizing monomers comprising a conjugated diene monomer in the presence of a lathanide-based coordination polymerization catalyst activated with a magnesium compound of formula 1where R1 is phenylene, or a linear or branched alkane diyl group containing 2 to 10 carbon atoms, or a combination of one or more phenylene groups and one or more linear or branched alkane diyl groups containing 1 to 10 carbon atoms;Q is of formula 2 or 3where R2 is phenyl, or a linear or branched alkyl group containing 2 to 10 carbon atoms;where R3 and R4 are independently phenyl or a linear or branched alkyl group containing 1 to 10 carbon atoms, or R2 and R3 taken together with the nitrogen atom represent a nitrogen containing heterocyclic group containing from 4 to 12 carbon atoms.