Figure 5. Relative radiation resistance of thermosetting resins

DOE-HDBK-1132-99

As the saturation level in the body of the bulk material is reached, the dissolved

tritium begins to emerge from the unexposed side of the material surface,

where it then begins to move through the mono-molecular layers of water vapor

on that side. In the initial stages, the pattern of the tritium moving into these

mono-molecular layers tends to resemble the reverse of that described in the

surface contamination model described above (i.e., the tritium is incorporated

first into the very tightly bound, near-surface layers, then into the intermediate

layers, and finally into the loosely bound, outer layers). As the tritium saturation

levels in the body of the bulk material gradually reach steady-state, the tritium

levels moving into the mono-molecular layers gradually build over time, and the

Damage

Utility of Plastic

Incipient to mild

Nearly always usable

Mild to moderate

Often satisfactory

Moderate to severe

Limited use

Phenolic, glass laminate

Phenolic, asbestos filled

Phenolic, unfilled

Epoxy, aromatic-type curing agent

Polyurethane

Polyester, glass filled

Polyester, mineral filled

Diallyl Phthalate, mineral filled

Polyester, unfilled

Mylar

Silicone, glass filled

Silicone, mineral filled

Silicone, unfilled

Furane, resin

Melamine-formaldehyde

Urea-formaldehyde

Aniline-formaldehyde

105

106

107

108

109

1010

Gamma Exposure Dose, Rads (C)

FIGURE 5. Relative radiation resistance of thermosetting resins.

I-108