Phosphonate Polymer Viscosity Reducer for Drilling Fluids

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing viscosity reducers for drilling fluids degrade in high temperature aging conditions, particularly in salt water and high-density drilling fluids, failing to maintain effective viscosity reduction and rheological properties.

Innovation Solution

A phosphonate-containing polymer with specific structural units, formulated through olefinic solution polymerization, is used as a viscosity reducer, comprising monomers such as 2-acrylamide-2-methyl propanephosphonic acid, 2-acrylamide-2-methyl propane sulfonic acid, and acrylic acid, which maintains excellent temperature tolerance and salt resistance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If traditional polymers (acrylic acid and vinylsulfonic acid) or organic phosphates are used as viscosity reducers, then temperature tolerance performance is improved, but viscosity reducing effect degrades in salt water drilling fluids and high-density drilling fluids after high temperature aging

Engineering Contradiction:

Improvetemperature toleranceVSAvoidviscosity reducing effect

Core Design Contradiction:

TemperatureVSReliability

Solution Approach 1:

The patent uses a composite polymer structure containing both phosphonate groups and sulfonic acid groups. The phosphonate groups provide salt resistance and maintain viscosity reducing effect in salt water and high-density drilling fluids, while the sulfonic acid groups contribute to temperature tolerance. This composite structure resolves the contradiction by combining the advantages of different functional groups.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent changes the chemical composition parameters of the polymer by introducing phosphonate-containing monomers (such as 2-acrylamide-2-methyl propanephosphonic acid) alongside traditional acrylic acid and vinylsulfonic acid. This parameter change in molecular structure enables the polymer to maintain both temperature tolerance and effective viscosity reduction in challenging drilling fluid conditions.

Inventive Principle:

Principle #35Parameter changes

2Temperature

If organic phosphates are used as viscosity reducers, then temperature resistance is improved, but maintenance interval is shortened and application range is narrowed

Engineering Contradiction:

Improvetemperature resistanceVSAvoidmaintenance interval

Core Design Contradiction:

TemperatureVSDuration of action of moving object

Solution Approach 1:

The patent modifies the chemical structure from traditional organic phosphates to phosphonate-containing polymers. This structural parameter change provides superior thermal stability and extends the maintenance interval while broadening the application range to include salt water and high-density drilling fluids, overcoming the limitations of conventional organic phosphates.

Inventive Principle:

Principle #35Parameter changes

3Temperature

If polymers containing carboxyl and sulfonic acid groups are used, then temperature tolerance is improved, but viscosity reducing effect degrades in salt water and high-density drilling fluids

Engineering Contradiction:

Improvetemperature toleranceVSAvoidsalt water and high-density drilling fluid degradation

Core Design Contradiction:

TemperatureVSObject-affected harmful factors

Solution Approach 1:

The patent creates a composite polymer incorporating phosphonate groups alongside carboxyl and sulfonic acid groups. The phosphonate groups specifically address the harmful effect of salt water and high-density drilling fluids by providing electrostatic repulsion and steric hindrance that prevent polymer collapse, while maintaining the temperature tolerance provided by the other functional groups.

Inventive Principle:

Principle #40Composite materials

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 phosphonate-containing polymer achieves a viscosity reducing rate of 95.2% or higher and reduced filter loss, even after aging at 220°C, in various drilling fluid bases, outperforming traditional polymers and organic phosphates in maintaining fluid properties.

Implementation Method 1

the phosphonate-containing polymer achieves a viscosity reducing rate of 95.2% or higher... in various drilling fluid bases

Methodology Applied

Scientific EffectViscosity reduction:

Implementation Method 2

maintains excellent temperature tolerance and salt resistance... after aging at 220°C

Methodology Applied

Scientific EffectTemperature tolerance:

Implementation Method 3

maintains excellent temperature tolerance and salt resistance... in salt water drilling fluids

Methodology Applied

Scientific EffectSalt resistance:

Data Source

PatentUS9206342B2Phosphonate-containing polymer and use thereof and phosphonate-containing polymer viscosity reducer for drilling fluid

Publication Date: 2015.12.08 CHINA PETROLEUM & CHEMICAL CORP

AI summary

The present invention provides a phosphonate-containing polymer and use thereof and a phosphonate-containing polymer viscosity reducer for drilling fluid. The phosphonate-containing polymer comprises structural units expressed by formula (1), structural units expressed by formula (2), and structural units expressed by formula (3) and/or structural units expressed by formula (4), wherein, the ratio of the mole number of the structural units expressed by formula (1), mole number of the structural units expressed by formula (2), and total mole number of the structural units expressed by formula (3) and structural units expressed by formula (4) is 10-85:10-75:5-55. The phosphonate-containing polymer still has outstanding viscosity reducing effect after high-temperature aging when it is applied in brine drilling fluids and high-density drilling fluids.