The purpose of this paper is to describe recent developments toward manufacturing plastic direct drive targets containing (approximately)50 atm (at 25(degrees)C) deuterium tritium (D-T). Contemporary plastic microballoons are typically composed of three layers. The first layer is a thin polystyrene mandrel, the second is a thin Poly(vinyl alcohol) (PVA) coating used as the hydrogen permeation barrier, and the third is a thick plasma polymer coating (CH(sub 1.3)) that acts as both the structural support and the ablater for these targets. Although the PVA layer provides an adequate permeation barrier for D(sub 2) gas, the radiation damage from tritium degrades the permeation characteristics of PVA. In this paper we will describe: (1) measurements of the D(sub 2) leak rate into and out of plastic targets, (2) the effect heat treatment has on the permeability of plastic targets, (3) a nonlinear dependence of the permeability on the pressure gradient across the shell due to internal and external D(sub 2) pressure, (4) an efficient D(sub 2) gas fill procedure, (5) measurements of the D-T leak rate out of targets that were filled using previous fill procedures, (6) measurements of the D-T leak rate out of targets that were filled using a new fill procedure that reduces the free radical decomposition of the PVA, (7) radiation catalyzed exchange and surface damage of the targets, and (8) a proposed procedure for delivering D-T filled plastic targets
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