Progress and challenges in the fabrication of DPS shells for ICF

To improve the quality of deuterated polystyrene (DPS) shells, the synthesis and purification of DPS as well as the fabrication of DPS shells are investigated. The molecular weight and molecular weight distribution, measured by GPC-MALLS, are about 350 kg mol(-1) and less than 2.0, respectively. The results of TG and GC-MS indicate that the residual solvent is almost completely removed. DPS shells with similar to 300 mu m -2500 mu m diameter and similar to 10 mu m-100 mu m wall thickness are successfully prepared by a microfluidic device. The monodispersity of the diameter is much better than that of the wall thickness in a batch of DPS shells. The vacuoles can be suppressed by both reducing hydrophilic residues in DPS and adding some salts into the outer water phase (W2). The defects appearing during the drying process decrease by heat treatment, ethanol exchange, and lowered drying temperature. The results presented in this work not only provide guidelines for the preparation of DPS shells of better quality, but also indicate challenges for the future. (C) 2019 Author(s).