INUMESCENT TECHNOLOGY FOR THERMOSET RESINS
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INUMESCENT TECHNOLOGY FOR THERMOSET RESINS PHILIP S. RHODES BROADVIEW TECHNOLOGIES NOV. 14-15, 2005
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INUMESCENT TECHNOLOGY FOR THERMOSET RESINS. PHILIP S. RHODES BROADVIEW TECHNOLOGIES NOV. 14-15, 2005. INTUMESCENT TECHNOLGY. Provides fire protection by building a continuous char foam layer on the polymer surface when exposed to heat or flame. Different types of fire retardants. - PowerPoint PPT Presentation
Transcript of INUMESCENT TECHNOLOGY FOR THERMOSET RESINS
INUMESCENT TECHNOLOGY FOR THERMOSET RESINS
PHILIP S. RHODESBROADVIEW TECHNOLOGIES
NOV. 14-15, 2005
INTUMESCENT TECHNOLGY
Provides fire protection by building a continuous char foam layer on the polymer surface when exposed to heat or flame.
Different types of fire retardants
Halogenated additives and resins
Water releasing additivesIntumescing agents/ char formers
Activated intumescing agents
Halogenated additives and resins
PROS
Cost effectiveEfficient at low loading levels
CONS
Harmful thermal decomposition products
Dioxins produced when burned in resource recovery plants
Water releasing additives
PROS
Low cost
CONS
High loading levelsOnly provides short term protection
Intumescent agents
PROS
Non hazardous thermal decomposition products
Long term fire and thermal protection
CONS
High loading levels
Only work with select resins
May require synergists
Activated intumescent agents
PROS
Long term thermal protection
Low-moderate loading levels
Work with a wide variety of resins
CONS
Moderately expensive
Still require the right resin-intumescent agent match
Intumescent agents
How do they work?
Intumescent agents are catalysts for char formation
They convert to mineral acids when heated but are non acidic at temperatures below 200 C
Catalyze dehydration reactionsWork best with organic compounds that can undergo dehydration reactions
Classic dehydration reaction
R-OH + R’OH + ACID = R-O-R’ + HOH
= R-O-R + HOH
=R’-O-R’ + HOH
What types of compounds readily undergo dehydration
reactionsStarchesSugarsCellulosicsPentaerythritol
Starch
(C6 H10 O5)n
Pentaerythritol
C5 H10 O4
Can intumescent agents work if the carbons do
not contain a oxygen/nitrogen
functional group?
The answer is YES.
Two approaches to overcome a low number of functional groups
The addition of additives that contain a high number of functional groups such as pentaerythritol and melamine
Use of an activated intumescent agent
What is an activated intumescent agent?
An intumescent agent that will help add functional
groups onto hydrocarbons when they do not exist.
When polymers start thermal decomposition
what happens?Hydrogens are stripped off forming carbon-carbon double bonds
The hydrogen combines with oxygen in the vapor phase to produce water vapor and heat
The carbon bonds break and low molecular weight alkenes enter the vapor phase
These alkenes are further split and oxidized to produce CO, COO and HOH
What happens in the presence of an
activated intumescentHydrogens are stripped off forming carbon-carbon double bonds
The hydrogen combines with oxygen in the vapor phase to produce water vapor and heat
The water vapor adds back across the double bonds via a catalytic route
The hydroxyls formed combine to form thermally stable ether linkages that produce char
During this dehydration reaction water is released cooling the polymer via a ablative mechanism
Epoxy exampleFormulation
DER 331 10ANC. 350A 4.5
INTU. AC2BG 1.5
PROPERTIES(5 mil coating)Char yield 66%Char ht(mil) 1000Expansion 200 xProtection 40 m
Urethane exampleFormulation
Poly diol61
TMP 2.5Int AC2hph36.5
MDI 22.5
Properties(5 mil coating)Char yield 62%Char ht 250Expansion 50xProtection 29 m
Styrene acrylicFormulation
RH TR (50%s) 10Intu AC3WM 3
Properties(5 mil dry coating)Char yield 76%Char ht 450Expansion 90xProtection 36 m
PolypropyleneFormulation
Polpropylene 10Plasticizer
1Intu AC-3
3
Properties (5 mil film on steel) Char yield 70% Char ht 60 Expansion 12x Protection 18 m
