Pyroelectricity

1
Pyroelectricity

• GLY 4200 Lecture 4 Fall, 2012

2
Pyroelectricity Effect Diagram
3
Polarization

• Pi pi ?T
• where
• Pi is the polarization vector,
• pi are the pyroelectric coefficients, and
• ?T is the temperature change

4
PVDF

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

5
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