Electron irradiation

Electron irradiation is a process which involves using electrons, usually of high energy, to treat an object for a variety of purposes. This may take place under elevated temperatures and nitrogen atmosphere. Possible uses for electron irradiation include Sterilization (microbiology) and to cross-link polymers.

Electron energies typically varies from the keV to MeV range, depending on the depth of penetration required. The irradiation dose is usually measured in Gray (unit) but also in Mrads. Where 1Gy is equivalent to 100rad.

In polymers, an electron beam may be used on the material to induce effects such as chain scission (which makes the polymer chain shorter) and cross linking. The result is a change in the properties of the polymer which is intended to extend the range of applications for the material. The effects of irradiation may also include changes in crystallinity as well as microstructure. Usually, the irradiation process degrades the polymer. The irradiated polymers may sometimes be characterized using DSC, XRD, FTIR, or SEM.

In poly(vinylidene fluoride-trifluoroethylene) copolymers, high-energy electron irradiation lowers the energy barrier for the ferroelectric-paraelectric phase transition and reduces polarization hysteresis losses in the material [1] .

ee also

# Electron beam lithography
# Beta Particle
# Beta decay
# Sterilization (microbiology)

Examples of Irradiation

# Z.Y. Cheng, V. Bharti, T. Mai, T.-B. Xu, Q. M. Zhang, T. Ramotowski, K. A. Wright, R. Ting, "Effect of High Energy Electron Irradiation on the Electromechanical Properties of Poly(vinylidene Fluoride-Trifluoroethylene) 50/50 and 65/35 Copolymers", "IEEE Trans. on Ultrasonics, Ferroelectrics and Frequency Control", 47 (6), 1296-1307, Nov 2000.