Electrically Dissipative Polyurethane Foam for Pipeline Protection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing polyurethane (PU) foams lack electrical resistivity in the static dissipative range and often act as electrical shields, making them unsuitable for cathodic protection systems, particularly in trench breakers and pipeline pillows, due to limitations with carbon-based fillers that aggregate and affect mechanical properties.

Innovation Solution

A PU foam formulation comprising an isocyanate component, a polyether polyol with specific functionality and OH value, carbon black with a defined BET surface area, a blowing agent, and an amine catalyst, with carbon black content between 1.0 wt.% to 15.0 wt.%, to achieve electrical resistivity in the static dissipative range and maintain acceptable mechanical properties.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If carbon-based fillers are added to PU foam to achieve electrical conductivity, then electrical resistivity is improved, but mechanical properties deteriorate due to filler aggregation

Engineering Contradiction:
Improveelectrical resistivityVSAvoidmechanical properties
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The patent applies parameter changes by precisely controlling the BET surface area of carbon black particles (between 600-2000 m²/g) and adjusting carbon black content (1.0-15.0 wt.%). This optimization of physical parameters prevents particle aggregation while achieving the target electrical resistivity range of 1.0×10² to 1.0×10⁹ Ω.m, thereby maintaining mechanical properties.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite material system combining PU foam matrix with specifically controlled carbon black particles. The composite structure leverages the electrical conductivity of carbon black while the PU foam matrix maintains mechanical integrity, achieving both electrical and mechanical performance requirements simultaneously.

Inventive Principle:
Principle #40Composite materials

2Reliability

If conventional PU foam is used in cathodic protection systems, then insulation properties are maintained, but electrical resistivity is insufficient for static dissipative functionality

Engineering Contradiction:
Improveelectrical resistivityVSAvoidinsulation properties
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent modifies the electrical parameters of PU foam by incorporating carbon black with controlled surface area and content, transforming the material from a pure insulator to a static dissipative material with resistivity in the range of 1.0×10² to 1.0×10⁹ Ω.m, enabling cathodic protection functionality while maintaining appropriate insulation.

Inventive Principle:
Principle #35Parameter changes

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 formulated PU foam exhibits electrical resistivity within the static dissipative range (1.0×10^2 Ω.m to 1.0×10^9 Ω.m) and maintains acceptable mechanical properties, making it suitable for applications in trench breakers and pipeline pillows, enhancing cathodic protection systems.

Implementation Method 1

These materials allow the flow of static electric charges intermediate to those of anti-static and conductive materials

Methodology Applied
Scientific EffectElectrical conduction: Conduction (electrical)

Implementation Method 2

Polyurethanes, defined as polymeric substances having multiple urethane linkages

Methodology Applied
Scientific EffectPolyaddition reaction: Chemical Bonding

Data Source

PatentEP4149986B1Electrically dissipative polyurethane foams and use thereof in trench breakers or pipeline pillows
Publication Date: 2024.08.07 BASF SE

AI summary

The present invention relates to an electrically dissipative polyurethane foam (PU foam) and its use in trench breakers or pipeline pillows.