Azo Initiator Surface-Functionalized Proppants for Fracturing Fluids

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In hydraulic fracturing, there is a challenge in retaining polymeric materials within fracture networks to prevent environmental contamination, as they can migrate to groundwater sources and the surface, posing a significant environmental risk due to their slow degradation and toxicity.

Innovation Solution

A polymerization initiator with azo-groups and anchoring agents is used to surface-functionalize particles, such as silica or ceramic proppants, allowing for high-density polymer growth that adheres to the particles, preventing polymer migration through 'grafting-to' or 'grafting-from' polymerization schemes, thereby retaining polymers within the fracture networks.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If polymeric materials are used in fracturing fluids for viscosity modification, then fluid viscosity is improved, but polymer migration to groundwater and surface occurs causing environmental contamination

Engineering Contradiction:

Improveviscosity modificationVSAvoidenvironmental contamination

Core Design Contradiction:

Use of energy by moving objectVSObject-affected harmful factors

Solution Approach 1:

The patent introduces proppant particles as intermediary carriers that bind polymeric materials to their surfaces through surface functionalization. This mediator prevents direct migration of polymers into groundwater while maintaining their viscosity-modifying function in the fracturing fluid.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent segments the polymeric material by attaching it to individual proppant particles rather than using free polymer chains in the fluid. This segmentation confines the polymer function to specific locations within the fracture network, preventing migration.

Inventive Principle:

Principle #1Segmentation

2Use of energy by moving object

If high molecular weight polymers are used for effective viscosity modification, then fluid viscosity is improved, but polymer degradation and migration increase

Engineering Contradiction:

Improveviscosity modificationVSAvoidpolymer stability

Core Design Contradiction:

Use of energy by moving objectVSStability of the object's composition

Solution Approach 1:

Proppant particles serve as stable intermediary carriers that anchor high molecular weight polymers, preventing their degradation and migration while maintaining their viscosity-modifying capabilities throughout the fracturing operation.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent applies preliminary surface functionalization to proppant particles before introducing polymers, creating pre-prepared anchoring sites that securely bind polymers and prevent subsequent migration or degradation.

Inventive Principle:

Principle #10Preliminary action

3Ease of operation

If friction reducers are added to prevent turbulence, then fluid flow is improved, but polymer migration occurs reducing effectiveness

Engineering Contradiction:

Improvefluid flowVSAvoidpolymer retention

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The patent uses proppant particles with surface-bound polymers as intermediaries that maintain friction reduction benefits while eliminating polymer migration, thereby improving fluid flow reliability without sacrificing polymer retention.

Inventive Principle:

Principle #24Intermediary (Mediator)

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 solution effectively prevents the migration of polymeric additives from fracturing fluids, ensuring they remain in the fracture networks, reducing environmental contamination risks while maintaining high molecular weight polymers for effective viscosity modification.

Implementation Method 1

an initiator can include an azo-group and first and second anchoring agents on different ends of the azo-group

Methodology Applied

Scientific EffectFree radical generation: Decomposition (biological)

Implementation Method 2

first and second anchoring agents on different ends of the azo-group

Methodology Applied

Scientific EffectCovalent bonding: Chemical Bonding

Data Source

PatentUS10400054B2Initiator for surface-based polymerization and use thereof

Publication Date: 2019.09.03 UNIVERSITY OF SOUTH CAROLINA

AI summary

Disclosed are polymerization initiators as may be utilized for addition of polymers to a substrate surface. The initiators are azo-based initiators that include multi-functionality through addition of multiple anchoring agents to an inner azo group. Disclosed polymerization initiators can be utilized to form high density and high molecular weight polymers on a surface such as a particulate surface. Formed materials can be beneficial in one embodiment in fracking applications, providing composite proppant/polymer materials that can prevent leakage of polymers from a subterranean geologic formation.