1

B. Roduit (1), P. Guillaume (2), S. Wilker (3), P. Folly (4), A. Sarbach (4), B. Berger (4),

J. Mathieu (4), M. Ramin (5), B. Vogelsanger (5)

(1) AKTS AG, http://www.akts.com, TECHNOArk 3, 3960 Siders, Switzerland(2) PB Clermont s.a., http://www.pbclermont.be, Rue de Clermont 176, 4480 Engis, Belgium(3) Bundeswehr Institute for Materials (WIWEB), Grosses Cent, 53913 Swisttal-Heimerzheim, Germany(4) armasuisse, Science and Technology, http://www.armasuisse.ch, 3602 Thun, Switzerland(5) Nitrochemie Wimmis AG, http://www.nitrochemie.com, 3752 Wimmis, Switzerland

www.akts.com

ESTAC - 10ESTAC - 1022 - 27 August 201022 - 27 August 2010

Rotterdam – The NetherlandsRotterdam – The Netherlands

Estimation of Life Assessment of Energetic Estimation of Life Assessment of Energetic Materials Materials

using Advanced Kinetic Elaboration of HFC using Advanced Kinetic Elaboration of HFC SignalsSignals

www.armasuisse.ch www.nitrochemie.com www.pbclermont.bewww.pbclermont.be www.bwb.org

2

TheThe preciseprecise prediction prediction of the degradationof the degradation of materialsof materials

TGTG DSCDSC

HFCHFC CLCLHPLCHPLC

3

TheThe preciseprecise prediction prediction of the degradationof the degradation of materialsof materials

TGTG DSCDSC

HFCHFC CLCLHPLCHPLC

Temperature (°C)230220210200190180170160150

He

atF

low

(W

/g)

8

6

4

2

0

-2

Exo

Heat : -121.682 (J/g)

.

4

More preciseMore precise measurementmeasurement of theof the

thermal agingthermal aging of of

energetic materialsenergetic materials

-Applications of Applications of isothermal microcalorimetryisothermal microcalorimetry

(HFC)(HFC)

5

TheThe preciseprecise prediction prediction of the degradationof the degradation of materialsof materials

TGTG DSCDSC

HFCHFC CLCLHPLCHPLC

Temperature (°C)230220210200190180170160150

He

atF

low

(W

/g)

8

6

4

2

0

-2

Exo

Heat : -121.682 (J/g)

.

6

TheThe preciseprecise prediction prediction of the degradationof the degradation of materialsof materials

TGTG DSCDSC

CLCLHPLCHPLC

Temperature (°C)230220210200190180170160150

He

atF

low

(W

/g)

8

6

4

2

0

-2

Exo

Heat : -121.682 (J/g)

.

7

Experimentally :Experimentally :Just few temperaturesJust few temperatures

8

reaction progress

temperature

timepredictions??experiments

APPLICATION OF HFCAPPLICATION OF HFC

50°C < T < 100°C50°C < T < 100°C

T1

T2

T3

days < t < monthsdays < t < months

0 % < 0 % < < 5 % < 5 %

The use of HFC enables to gain advanced The use of HFC enables to gain advanced knowledge on the reaction rate at the early stage knowledge on the reaction rate at the early stage

of the decomposition of the decomposition

9

7 years !7 years !

Reaction Reaction raterate

Reaction Reaction progressprogress

Well Well defineddefined

Well Well defineddefined

Because baseline is well defined Because baseline is well defined

50°C50°C

10

Isoconversional methodsIsoconversional methods

Uncertainity of thermokinetic analysis : the stages and physico-chemical reaction pathways are generally unknown

Observed thermal event can be the sum of thermal events created during certain stages of the reaction which are not always known

Temperature (°C)300280260240220200

He

atF

low

|-b

s (W

/g)

2.75

2.5

2.25

2

1.75

1.5

1.25

1

0.75

0.5

0.25

0

Exo

3-Methyl-4-nitrophenol_DSC_dyn_2G

??What do you see below? Young women? Old man? Or both?

11

Isoconversional method

Reaction rate expressed by the Arrhenius equation

Reaction rate at a given reaction progress

is only a function of the temperature

A’() and E() are the pre-exponential factor and apparent activation energy

Isoconversional methods (model free): Three main modifications of isoconversional method are applied in the literature: - Differential (Friedman) - Integral (Flynn-Ozawa-Wall) - Advanced integral based on non-linear procedure (Vyazovkin)

Differential isoconversional method

=

12

100

110

120

130

140

150

160

0.1 1 10 100 1000heat release Q /J·g -̂1

acti

vati

on e

nerg

y E

/kJ·

mol

^-1 A

EE = 138 kJ/mol = 138 kJ/mol

Activation energy E as a function of the heat releaseActivation energy E as a function of the heat release

13

1.E-09

1.E-08

1.E-07

1.E-06

1.E-05

1.E-04

1.E-03

0.0001 0.001 0.01 0.1 1 10 100time /year

heat

flo

w /W

·g^-

1

30°C

40°C

50°C60°C

70°C

80°C89°C

20°C10°C

Ia

1.E-09

1.E-08

1.E-07

1.E-06

1.E-05

1.E-04

1.E-03

0.0001 0.001 0.01 0.1 1 10 100time /year

heat

flo

w /W

·g^-

1

50°C60°C

70°C

80°C89°CIa

1.E-09

1.E-08

1.E-07

1.E-06

1.E-05

1.E-04

1.E-03

0.0001 0.001 0.01 0.1 1 10 100time /year

heat

flo

w /W

·g^-

1

50°C60°C

70°C

80°C89°CIa

1.E-09

1.E-08

1.E-07

1.E-06

1.E-05

1.E-04

1.E-03

0.0001 0.001 0.01 0.1 1 10 100time /year

heat

flo

w /W

·g^-

1

60°C

70°C

80°C89°CIa

1.E-09

1.E-08

1.E-07

1.E-06

1.E-05

1.E-04

1.E-03

0.0001 0.001 0.01 0.1 1 10 100time /year

heat

flo

w /W

·g^-

1

60°C

70°C

80°C89°CIa

1.E-09

1.E-08

1.E-07

1.E-06

1.E-05

1.E-04

1.E-03

0.0001 0.001 0.01 0.1 1 10 100time /year

heat

flo

w /W

·g^-

1

70°C

80°C89°CIa

1.E-09

1.E-08

1.E-07

1.E-06

1.E-05

1.E-04

1.E-03

0.0001 0.001 0.01 0.1 1 10 100time /year

heat

flo

w /W

·g^-

1

70°C

80°C89°CIa

THERMAL AGING

14

THERMAL AGING

0.01

0.1

1

10

100

1000

0.001 0.01 0.1 1 10 100time /year

heat

rel

ease

/J·g

^-1

30°C40°C

50°C60°C70°C80°C89°C

20°C10°C

Ib

15

STANAG 2895STANAG 2895A2 (Hot dry)A2 (Hot dry)

Beijing Beijing

0

10

20

30

40

50

60

0 2 4 6 8 10time /year

tem

pera

ture

/°C

16

The assumption that the reaction rate the reaction rate da/dtda/dt

at a given reaction progress at a given reaction progress is only a function of the temperatureis only a function of the temperature

(differential isoconversional analysis) is acceptable.is acceptable.

It can be applied for a precise life assessment of energetic materials

=

17

fast experimentsfast experiments

(<(<10 hours)10 hours)

very precise predictionsvery precise predictions((±± 0.1%)

long term predictionslong term predictions

(>(>1 year)1 year)

ConclusionConclusion

Temperature (°C)230220210200190180170160150

He

atF

low

(W

/g)

8

6

4

2

0

-2

Exo

Heat : -121.682 (J/g)

.

DSCDSCHFCHFC

??

18

fast experimentsfast experiments

(<(<10 hours)10 hours)

very precise predictionsvery precise predictions((±± 0.1%)

long term predictionslong term predictions

(>(>1 year)1 year)

ConclusionConclusion

If you want to perform fast experiments (DSC) and get long term predictions using thermokinetics do not expect very precise predictions.

If you want to perform fast experiments (DSC) and get very precise predictions using thermokinetics do not expect long term predictions.

If you want to achieve long term predictions and expect very precise predictions using thermokinetics do not perform fast experiments (DSC). Do long term isothermal microcalorimetric measurements (HFC) and perform thermokinetics.

19

fast experimentsfast experiments

(<(<10 hours)10 hours)

very precise predictionsvery precise predictions((±± 0.1%)

long term predictionslong term predictions

(>(>1 year)1 year)

ConclusionConclusion

Temperature (°C)230220210200190180170160150

He

atF

low

(W

/g)

8

6

4

2

0

-2

Exo

Heat : -121.682 (J/g)

.

DSCDSCHFCHFC

??

20AAdvanceddvanced KKinetics and inetics and TTechnologyechnology SSolutionsolutions

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