Insulation Panel Fire Barrier Using Expandable Graphite

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Solution Overview

Problem

There is a need for building insulation products that combine excellent thermal insulation with improved fire behavior, as highly insulated buildings pose challenges for passive fire protection, and existing solutions with metal facings may not be feasible or desirable in all applications.

Innovation Solution

The development of insulation panels with a non-steel based facing, such as a combustible material or low melting point thin metal foil, and a fire barrier layer containing a dispersion of expandable graphite in a polyisocyanate polymer matrix, which enhances fire behavior by protecting the insulating foam from flame impingement and preventing fast flame propagation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a non-steel based facing (combustible material or low melting point thin metal foil) is used, then the panel achieves good thermal insulation and adaptability, but the fire behavior deteriorates

Engineering Contradiction:
ImproveadaptabilityVSAvoidfire behavior
Core Design Contradiction:
Adaptability or versatilityVSObject-affected harmful factors

Solution Approach 1:

A fire barrier layer is introduced as an intermediary component between the non-steel based facing and the insulating foam layer. This barrier layer, containing expandable graphite dispersed in a polymer matrix, prevents direct flame contact with the combustible facing and foam, thereby protecting the thermal insulation performance while improving fire behavior to meet Euroclass Bs1d0 classification.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The fire barrier layer is constructed as a composite material system combining expandable graphite particles dispersed in a polymer matrix (polyester, polyacrylonitrile, polyvinylidene fluoride, or polytetrafluoroethylene). This composite structure provides both fire protection functionality and maintains the flexibility of non-steel facings, enabling the panel to achieve both adaptability and improved fire behavior.

Inventive Principle:
Principle #40Composite materials

2Object-affected harmful factors

If a fire barrier layer with expandable graphite is added, then the fire behavior improves, but the device complexity increases

Engineering Contradiction:
Improvefire behaviorVSAvoiddevice complexity
Core Design Contradiction:
Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The fire barrier layer is applied locally only at the critical interface between the facing and the insulating foam, rather than throughout the entire panel. This localized application provides fire protection precisely where it is most needed (at the flame exposure surface) while minimizing the overall complexity and material usage of the panel structure.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The fire barrier layer utilizes parameter changes in the expandable graphite material - specifically, its ability to undergo rapid volume expansion when exposed to fire temperatures. This phase change behavior allows the barrier to automatically activate and provide fire protection only when needed, without requiring complex control systems or additional structural elements.

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 proposed solution meets Euroclass Bs1d0 classification standards by reducing fire growth rate, smoke production, and heat release, while maintaining excellent thermal insulation properties, making it suitable for various construction applications.

Implementation Method 1

The fire barrier layer includes a dispersion of expandable graphite in a polyisocyanate polymer matrix and the amount of expandable graphite per unit area is 200-1250g/m2

Methodology Applied
Scientific EffectExpandable graphite expansion: Intumescent Materials

Implementation Method 2

Insulating products that include polymer foams provide good thermal insulation

Methodology Applied
Scientific EffectThermal insulation: Thermal Insulation

Data Source

PatentEP3132099B1Panel with fire barrier
Publication Date: 2018.12.26 DOW GLOBAL TECHNOLOGIES LLC
  • EP3132099B1 patent drawingFigure 1
  • EP3132099B1 patent drawingFigure 2
  • EP3132099B1 patent drawing

AI summary

An insulation panel includes a first non-steel based facing that is a combustible material, a glass-fleece based material, or a low melting temperature thin metal foil; an insulating foam layer; and a fire barrier layer adjacent to the first non-steel based facing and between the first non-steel based facing and the insulating foam layer. The fire barrier layer includes a dispersion of expandable graphite in a polyisocyanate polymer matrix and the amount of expandable graphite per unit area is at least 50 g/m2.