THERMAL ANALYSIS OF POLYMER FLAMMABILITY

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(No Transcript)
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RANKING FLAMMABILITY USING SMALL SCALE TEST
OUTLINE OF TALK

• Flammability
• Ignition Resistance (0?, 90?, 60?,45? Bunsen
  burner)
• Fire Behavior (OSU, seat cushion test, radiant
  panel)
• Microscale Combustion Calorimetry
• Operation and Theory
• Comparison of Results for Hidden Materials
• Heat Release Rate (OSU)
• Bunsen Burner tests
• Smoke Density
• Radiant Panel
• 1/4-scale tests

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FAA FLAMMABILITY TESTS
Bunsen Burner Tests
OSU HRR Test
Seat Cushion Oil Burner Test
Radiant Panel Test
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SCALES OF FLAMMABILITY TESTING
Microscale Combustion Calorimetry
Flame Tests
Fire Tests
Bench-Scale
Component-Scale
Metric Ton
Gram
Milligram
Kilogram
SAMPLE SIZE
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STEADY BURNING Nylon 6 data
2000
PA6
1500
Slopes HRP
1000
Heat Release Rate, kW/m2
HRR0 (kW/m2)
Ignitability
500
HRP
230
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Intercepts HRR0
148
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Fire Response
0
20
40
60
80
100
120
External Heat Flux, kW/m2
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IGNITABILITY UL 94 vs. HRR0
41 polymers, blends, and composites.
HB
V2
UL 94 Rating
Self-Propagating
Self-Extinguishing
V1
V0
-400
-200
0
200
400
600
HRR0, kW/m2 (in cone calorimeter)
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HEAT RELEASE RATE AND HEAT RELEAE CAPACITY
The Heat Release Capacity (HRC), is related to
the heat release rate (HRR) in flaming combustion
HRR (????) HRC ? HRC

• Flaming combustion
• efficiency

? Density
? Pyrolysis depth
? Surface heating rate
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HEAT RELEASE CAPACITY AND FLAMMABILITY
IGNITABILITY
Self extinguishing when
HRR0 ? HRR HRC
HEAT RELEASE RATE
For a particular heat flux (e.g., 3.5 W/cm2)
HRR ? HRC
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MEASURING HEAT RELEASE CAPACITY
Gas Scrubber

Gas Flow- meter
O2 Meter
Exhaust
Combustion
O2
DAQ
N2
Pyrolysis
Sample
Pyrolysis-Combustion Flow Calorimetry (PCFC)
Flaming Combustion
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FLAMMABILITY TESTING OF MILLIGRAM SAMPLES
FAA/Galaxy Invention
TGA Combustion Accessory
Stand Alone Device
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HEAT RELEASE CAPACITY FROM PCFC
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PCFC DATA FIRE TESTS
Relevant FAA Flammability Test
Combustion Calorimetry Data

• OSU HRR
• Bunsen Burner Ignition
• Radiant Panel
• Oil Burner Seat Test

PMMA
Burning Rate
Heat of Combustion
Heat Release Rate (W/g)

• Oxygen Bomb Calorimeter

• Setchkins Furnace
• Glow Wire Ignition

Ignition Temperature
Temperature (C)
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IGNITION RESISTANCE (UL 94) AND HRC
UL 94
Rating
HB
V2
Flammability
V1

V0
10

100

1000

10,000

Heat Release Capacity, J/g-K
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IGNITION RESISTANCE (LOI) AND HRC
100

80

60

Limiting Oxygen Index (LOI), O2
40

20

0

10
100
1000
10,000


Heat Release Capacity, J/g-K

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12 SECOND VERTICAL BURN TEST AND HRC
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Hidden Materials
8
6
Burn Time (seconds)
4
Burn Length (cm)
2
0
-2
HRC (J/g-K)
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FIRE (HRP) AND MATERIAL (HRC) PROPERTIES
Engineering Plastics
Commodity Plastics
Hidden Area Components
????
HRP

q?net
HRC
?
HEAT RELEASE PARAMETER
?
cp
Slope should be relatively constant for plastics
for well-ventilated burning
HRC (J/g-K)
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HRR (OSU PEAK) AND HRC
Engineering Thermoplastics (0.060 inch sheet)
OSU Peak HRR, kW/m2
R 0.72
Heat Release Capacity, J/g-K
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NBS SMOKE DENSITY AND HRC
Hidden Materials
s
Smoke Density, D
HRC (J/g-K)
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RADIANT PANEL TEST AND HRC
Hidden Materials
BURN TIME, seconds
HRC (J/g-K)
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TEMPERATURE RISE AND HRC OF INSULATION BAGS
INTERMEDIATE SCALE TEST AND HRC
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HIDDEN MATERIALS Accident Investigation
Metalized Mylar Bag
Hook Loop (married)
Cockpit Headliner
F L A MMA B L E
GRP Duct
Plastic Conduit
Ceiling Panel (back)
Flexside Duct
Pass OSU HRR
Pass Bunsen Burner
Ceiling Panel (face)
Silicone Rubber
Foam Core Duct
HRC (J/g-K)
SwissAir 111 Database
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FLAMMABILITY (HRC) RANKING BY COST
1000
Common Plastics
PE
PP
ABS
PS
NYLON 66
PPO
Flammable
Epoxy
PU
Polyarylate
PET
PMMA
Polysulfone
PC
(J/g-K)
PVF (TEDLAR)
PVC (rigid)
PES
POM
PPS
PEEK
100
PEI
LCP's
PEK
Phenolic
PPSF
PAI
Current Aircraft
Specialty Plastics
Flammability
(KAPTON) PI
10
Resin

Plastic

FAA Research Plastics
FAA Goal
0.1
1
10
100
Price of Plastic (/lb)
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CONCLUSIONS
Heat release capacity HRC is a qualitative
predictor of fire performance and flammability of
aircraft materials Swelling, dripping, and
barrier formation influence flame/fire tests but
do not effect HRC.