Measuring Thermal Conductivity using a Student-built Apparatus and Modulated Differential Scanning

Calorimeter

Shera Demchak Research Advisors Dr. Bill Heffner & Dr. Ray Pearson

WHAT IS HEAT FLOW? Heat flow is the transfer of heat

energy from a warmer region to a colder region

Modes of Heat Transfer: Convection, Radiation, Conduction

Differential Scanning Calorimetry is a method for measuring Thermal Conductivity as recommended by American Society for Testing and Materials (ASTM)

PRICES $$$

Q2000 TA Instruments DSC

Student-Built Apparatus

~ $ 115,000 (retail) ~ $ 65,000 (ed. discount)

________?

PRICES $$$

Q2000 TA Instruments DSC

Student-Built Apparatus

~ $ 115,000 (retail) ~ $ 65,000 (ed. discount)

< $ 100

The Student-Made Apparatus

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VOLTAGE DATA

First Peak: Aluminum

Second Peak: PMMA

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delta

T

delta

Q

time (min)

RAW DATA

dQ dT

Conceptually: Conductors have a HIGH dQ and LOW dT,. Insulators have a LOW dQ and HIGH dT.

*dQ and dT are in digital units.

THE STUDENT-BUILT APPARATUS

dQ = k * (A/L) * ΔT

ΔT = change in temperature (K) (A/L) = area of sample / length (m) k = Thermal Conductivity Constant (W / K m) dQ = Heat Flow (W)

-0.2

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0 0.2 0.4 0.6 0.8 1 1.2

Expe

rim

enta

l K v

alue

s

Literature K Values

Student-Built Compared to Literature

Student-built Apparatus

Polymethyl Methacrylate

Teflon

Pyrex

High-density Polyethylene

Foam

MODULATED DIFFERENTIAL SCANNING CALORIMETER (MDSC)

REFERENCE DISC

SAMPLE DISC

THERMOCOUPLE

EXPERIMENTAL THERMAL CONDUCTIVITY

k

k

HOW THE DIFFERENTIAL CALORIMETER SCANNER WORKS

-0.2

0

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1.2

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0 0.2 0.4 0.6 0.8 1 1.2

Expe

rim

enta

l K v

alue

s

Literature K Values

Comparing the Student-Built Apparatus with the DSC

DSC

Student-built Apparatus

Polymethyl Methacrylate

Teflon

Pyrex

High-density Polyethylene

Foam

The student-built apparatus is cheaper, simpler, and faster!

Acknowledgments I would like to thank the following people for training me,

mentoring me, bandaging me, and offering me their advise during my hours in the lab.

Dr. Heffner and Dr. Pearson Lauren Bacigalupo Maria Salamon Marisa Sanders Amelia Labak Steve Antalics

Further Reading: ASTM Standard E1952, 2011, "Thermal Conductivity and Thermal Diffusivity by Modulated Temperature Differential Scanning Calorimetry," ASTM International, West Conshohocken, PA, 2011, wwwastm.org. Hatakeyama, T. and F. X. Quinn"Thermal Analysis: Fundamentals and Applications to Polymer Science." 2nd Edition. John Wiley & Sons. 1999.

Thank you to the International Materials

Institute for its support!