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Pyroelectricity

GLY 4200 – Lecture 4 –Fall, 2012

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Pyroelectricity Effect Diagram

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Polarization

• Pi = pi ΔT

• where Pi is the polarization vector,

pi are the pyroelectric coefficients, and

ΔT is the temperature change

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PVDF

• Polymers - such as Polyvinylidenefluoride (PVDF) - consist of long chains of  molecules, as is shown in the image above

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Pyroelectricity in Polymers

• Certain molecular groups act as dipoles and can be oriented in an electric field• When the poled polymer is exposed to heat, the sample expands, causing the

dipole spacing to change, and generating a charge