Shape Memory Polyphenylene Sulfide for Downhole Sealing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current shape memory polymers (SMPs) lack sufficient thermal and chemical stability and are costly, limiting their effectiveness in downhole applications such as sealing and constricting boreholes.
Innovation Solution
A process for producing shape memory polyphenylene sulfide involves curing polyphenylene sulfide in the presence of oxygen, followed by comminution, molding, and heat treatment to create cured polyphenylene sulfide particles with enhanced thermal stability, chemical resistance, and improved shape memory properties, including rapid recovery and near-quantitative recovery of pre-compression dimensions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional shape memory polymers are used, then shape memory functionality is achieved, but thermal stability and chemical resistance are insufficient
Solution Approach 1:
The patent changes the chemical composition parameters by using polyphenylene sulfide as the base polymer and incorporating specific crosslinking agents. The curing process transforms the polymer from a thermoplastic state to a thermosetting state with enhanced thermal stability. This parameter change in material composition directly resolves the contradiction by achieving high thermal stability while maintaining manufacturability through established curing processes.
Solution Approach 2:
The patent creates a composite material system by combining polyphenylene sulfide with crosslinking agents to form a cured network structure. This composite approach integrates the shape memory functionality with the thermal and chemical stability of the crosslinked polyphenylene sulfide matrix, resolving the contradiction between reliability and ease of manufacture.
2Reliability
If conventional shape memory polymers are used, then shape memory functionality is achieved, but chemical resistance is insufficient
Solution Approach 1:
The patent modifies the chemical resistance parameters by selecting polyphenylene sulfide, which inherently possesses excellent chemical resistance, and enhancing it further through crosslinking. The curing process creates a dense crosslinked network that resists chemical penetration and degradation, achieving high chemical resistance while maintaining ease of manufacture through standard curing procedures.
3Reliability
If shape memory polymers are used in downhole applications, then sealing and constricting functions are achieved, but cost is excessive
Solution Approach 1:
The patent employs a cost-effective approach by using polyphenylene sulfide, a relatively inexpensive engineering polymer, as the base material. The material is designed for single-use downhole applications where it provides reliable sealing and constricting functions. After deployment, the material is discarded, eliminating the need for expensive recovery or reuse infrastructure. This disposable strategy resolves the contradiction between high performance and low cost.
Solution Approach 2:
The patent changes the material selection parameters from expensive specialty shape memory polymers to cost-effective polyphenylene sulfide. By optimizing the curing and crosslinking parameters, the patent achieves the required downhole performance at a lower material cost, resolving the contradiction between reliability and cost.
4Reliability
If polyphenylene sulfide is cured to enhance thermal stability, then thermal stability improves, but shape memory properties are lost
Solution Approach 1:
The patent applies partial curing to the polyphenylene sulfide, maintaining sufficient uncured polymer chains to preserve shape memory functionality while developing enough crosslinked structure to provide thermal stability. This partial action approach resolves the contradiction by achieving both thermal stability and shape memory properties simultaneously, rather than complete curing which would eliminate shape memory.
Solution Approach 2:
The patent optimizes the curing parameters including temperature, time, and crosslinking agent concentration to achieve the right balance. By controlling these parameters, the patent creates a material with both thermal stability from crosslinking and shape memory properties from remaining polymer chain mobility, resolving the contradiction between these two properties.
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 resulting shape memory polyphenylene sulfide exhibits improved thermal stability, chemical resistance, and rapid shape recovery, making it suitable for demanding downhole applications with enhanced performance compared to conventional SMPs.
Implementation Method 1
Shape memory polymers (SMPs) are polymers that regain their original shape when heated above their glass transition temperature (Tg)
Implementation Method 2
Shape memory polymers (SMPs) are polymers that regain their original shape when heated above their glass transition temperature (Tg)
Data Source
AI summary
Disclosed is a process for making shape memory polyphenylene sulfide, comprising: curing polyphenylene sulfide to produce cured polyphenylene sulfide; comminuting the cured polyphenylene sulfide to form cured polyphenylene sulfide particles; disposing the cured polyphenylene sulfide particles in a mold; heating the mold for flowing the cured polyphenylene sulfide; compressing, by applying a compressive force, the cured polyphenylene sulfide; cooling the cured polyphenylene sulfide; relieving the compressive force; and de-molding the cured polyphenylene sulfide to produce the shape memory polyphenylene sulfide.