Fluorinated Polyurethane Membrane for Sensor Film Reproducibility

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing compositions for forming synthetic membranes face challenges in reproducibility and analyte diffusivity, often requiring strong solvents that pose health and safety concerns and can dissolve polymer layers, limiting their use in sensor applications.

Innovation Solution

A composition comprising 90-99.5% solvent and 0.5-10% polymer mixture, where the polymer mixture consists of 85-99.5% polyurethane and 0.5-15% free hydrophilic polymer, with the polyurethane having a backbone or endgroups comprising C2-C16 fluoroalkyl or C2-C16 fluoroalkyl ether, enhancing mechanical properties and compatibility with sensors.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If strong high boiling point organic solvents such as DMAc or DMF are used to overcome microphase separation and improve film formation, then film quality and reproducibility are improved, but health and safety concerns arise and solvent removal becomes difficult

Engineering Contradiction:
Improvefilm formation reproducibilityVSAvoidhealth and safety concerns
Core Design Contradiction:
Manufacturing precisionVSObject-affected harmful factors

Solution Approach 1:

The patent changes the solvent parameters by selecting solvents with specific boiling points and polarities that balance film formation quality with ease of removal. The composition uses solvents that can dissolve the fluorinated polyurethane and hydrophilic polymer blend adequately while being safer and easier to remove than traditional strong solvents like DMAc or DMF.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent uses a composite polymer system consisting of fluorinated polyurethane blended with hydrophilic polymers (such as polyvinylpyrrolidone, polyethylene oxide, or polyacrylic acid). This composite approach allows the use of milder solvents while maintaining film quality, as the hydrophilic polymer component aids in film formation and stability without requiring strong solvents.

Inventive Principle:
Principle #40Composite materials

2Manufacturing precision

If strong high boiling point organic solvents such as DMAc or DMF are used to overcome microphase separation and improve film formation, then film quality and reproducibility are improved, but the solvents may dissolve polymer layers on sensors

Engineering Contradiction:
Improvefilm formation reproducibilityVSAvoidcompatibility with sensor polymer layers
Core Design Contradiction:
Manufacturing precisionVSAdaptability or versatility

Solution Approach 1:

The patent changes the solvent parameters to select solvents with appropriate solvating power that is sufficient to form high-quality films from the fluorinated polyurethane blend but not so strong as to dissolve the polymer layers on sensor surfaces. This parameter optimization ensures compatibility with various sensor types while maintaining film formation quality.

Inventive Principle:
Principle #35Parameter changes

3Reliability

If blends of dissimilar polymers such as hydrophilic polymer and hydrophobic polyurethane are used, then analyte flux control is improved, but microphase separation occurs reducing reproducibility

Engineering Contradiction:
Improveanalyte flux controlVSAvoidfilm formation reproducibility
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The patent uses a composite material system where fluorinated polyurethane (hydrophobic component) is blended with hydrophilic polymers in specific ratios. The fluorinated polyurethane provides the hydrophobic matrix for analyte flux control, while the hydrophilic polymer components (such as PVP, PEO, or polyacrylic acid) provide hydrophilic domains that control analyte diffusion. This composite approach maintains phase separation necessary for flux control while achieving reproducible film formation through optimized composition ratios.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The patent creates local quality variations within the membrane by forming hydrophilic domains dispersed in a hydrophobic matrix. The hydrophilic polymer segments create localized hydrophilic regions that control analyte diffusion pathways, while the fluorinated polyurethane backbone provides the overall hydrophobic structure. This local quality differentiation enables simultaneous control of analyte flux and reproducible film formation.

Inventive Principle:
Principle #3Local quality

4Strength

If fluorinated polyurethane with specific backbone or endgroup modifications is used, then mechanical properties and anti-fouling are improved, but composition complexity increases

Engineering Contradiction:
Improvemechanical propertiesVSAvoidpolymer composition complexity
Core Design Contradiction:
StrengthVSDevice complexity

Solution Approach 1:

The patent applies local quality modification by introducing fluorinated groups at specific locations in the polyurethane structure - either in the backbone or as endgroups. This localized fluorination provides anti-fouling properties and enhanced mechanical characteristics without requiring complete structural redesign of the entire polymer. The fluorinated segments are concentrated in specific regions, providing the desired functionality while keeping the overall composition relatively simple.

Inventive Principle:
Principle #3Local quality

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 improves film formation reproducibility, mechanical properties, anti-fouling, health and safety, and solvent removal, while maintaining analyte permeability and oxygen permeability, making it suitable for a wider range of solvents and sensor applications.

Implementation Method 1

The surface modifying endgroups and backbone are such that the surface activity of such a polyurethane reflects the surface activity of the surface modifying endgroups rather than the backbone

Methodology Applied
Scientific EffectSurface activity: Surfactant

Implementation Method 2

the blend allows membranes having hydrophilic domains that control the diffusion of an analyte therethrough dispersed in a hydrophobic matrix

Methodology Applied
Scientific EffectDiffusion: Diffusion

Implementation Method 3

A composition for forming a membrane comprises from 90 to 99.5 wt %, based on the total weight of the composition, of a solvent and from 0.5 to 10 wt %, based on the total weight of the composition, of a polymer mixture

Methodology Applied
Scientific EffectEvaporation: Evaporation

Data Source

PatentUS11649353B2Synthetic membrane composition comprising a fluorinated polyurethane
Publication Date: 2023.05.16 DSM IP ASSETS BV

AI summary

Disclosed are compositions that may be useful for forming synthetic membranes, methods of forming membranes therefrom, and membranes. In an embodiment, a membrane comprises a free hydrophilic polymer and a polyurethane, the polyurethane comprising a backbone comprising the reaction product of a diisocyanate, a polymeric aliphatic diol, and, optionally, a chain extender, wherein the backbone comprises a C2-C16 fluoroalkyl or C2-C16 fluoroalkyl ether, or the polyurethane comprises an endgroup comprising a C2-C16 fluoroalkyl or C2-C16 fluoroalkyl ether.