Fluoroelastomer Curing with Bis Phthalonitrile
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
There is a need to improve the heat aging properties and identify novel curing systems for fluoropolymers, as existing technologies do not effectively address these requirements.
Innovation Solution
A curable composition comprising a partially fluorinated polymer with carbon-carbon double bonds, a bis phthalonitrile compound of specific Formula I, and optionally a polyhydroxy curative, or a fluorinated elastomeric gum with a peroxide curing system, which includes a peroxide and a coagent, to form a fluoroelastomer with enhanced properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If existing curing systems are used for fluoropolymers, then the curing process is simple, but the heat aging properties are insufficient
Solution Approach 1:
The patent uses a composite curing system combining peroxide and bis phthalonitrile compounds with fluoropolymer containing multiple functional groups (iodine, bromine, nitrile). This composite approach creates synergistic effects where the peroxide initiates crosslinking and the bis phthalonitrile compounds enhance the curing network, resulting in improved heat aging properties while maintaining manageable process complexity.
2Strength
If conventional fluoropolymer compositions are used, then the material composition is simple, but the physical properties such as elongation and strength are limited
Solution Approach 1:
The patent modifies the chemical composition parameters by incorporating bis phthalonitrile compounds with specific molecular structures containing multivalent benzene groups linked by oxygen or sulfur. These parameter changes in the curing agent structure enable enhanced crosslinking density and improved physical properties including elongation and tensile strength, while the systematic approach to composition maintains manufacturability.
3Stability of the object's composition
If traditional curing agents are used, then the curing process is straightforward, but the thermal aging resistance is inadequate
Solution Approach 1:
The bis phthalonitrile compounds act as intermediary substances that mediate between the peroxide curing system and the fluoropolymer matrix. These intermediaries facilitate enhanced crosslinking reactions and improve the thermal stability of the cured network, providing better thermal aging resistance while maintaining a systematic and manageable curing process.
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 described compositions result in fluoroelastomers with improved thermal aging and physical properties, such as increased elongation and retained strength, making them suitable for various industrial applications like hoses, seals, and gaskets.
Implementation Method 1
a peroxide curing system comprising a peroxide and a coagent
Implementation Method 2
wherein the backbone of the partially fluorinated polymer comprises carbon-carbon double bonds or is capable of forming carbon-carbon double bond
Implementation Method 3
a compound of Formula I wherein X1 and X2 are independently selected from O or S, and L comprises at least one multivalent benzene group
Data Source
AI summary
Described herein are fluoropolymer compositions comprising a bis phthalonitrile-containing compound. In one embodiment, the bis phthalonitrile-containing compound is used to crosslink a dehydrohalogenated polymer, and optionally with a polyhydroxy curative. In another embodiment, the bis phthalonitrile-containing compound is added to a composition comprising (i) a fluorinated elastomeric gum, wherein the fluorinated elastomeric gum comprises a fluoropolymer having a cure-site and (ii) a peroxide curing system.