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Pyroelectricity. GLY 4200 – Lecture 4 –Fall, 2014. Pyroelectricity Effect Diagram. Polarization. P i = p i Δ T where P i is the polarization vector, p i are the pyroelectric coefficients, and Δ T is the temperature change. PVDF.
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Pyroelectricity GLY 4200 – Lecture 4 –Fall, 2014
Polarization • Pi = pi ΔT • where • Pi is the polarization vector, • pi are the pyroelectric coefficients, and • ΔT is the temperature change
PVDF • Polymers - such as Polyvinylidenefluoride (PVDF) - consist of long chains of molecules, as is shown in the image above
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