聚苯乙烯相对分子量对薄壁聚苯乙烯空心微球质量的影响

Investigation into preparation of thin-walled polystyrene hollow microspheres for ICF

激光惯性约束聚变(ICF)作为探索受控核聚变的有效途径,有望获得清洁无污染的能源,而薄壁聚苯乙烯(PS)空心微球是ICF物理实验中亟需的一类微球。针对薄壁空心微球因径厚比(直径/壁厚)增大导致其在干燥、使用中易开裂的问题,研究了PS原料对薄壁微球质量的影响,探讨了其影响机制。结果表明:当油相PS质量分数为4%时,随着油相粘度增加,W1/O/W2复合乳粒稳定性逐渐提高;当油相质量分数不低于8%时,复合乳粒稳定性良好。PS原料对微球表面粗糙度影响较小,微球球形度和壁厚均匀性随初始油相粘度的增大而降低,在干燥过程中微球开裂率随原料力学性能提高而减小。在外水相中引入氟苯(FB)液滴,延缓固化速率,可减小油相粘度增加对微球球形度和壁厚均匀性的不利影响。

As an effective way to explore controlled nuclear fusion, laser inertial confinement fusion(ICF) is expected to obtain clean and pollution-free energy. Thin-walled polystyrene(PS) hollow microspheres are a type of microspheres urgently needed in ICF physics experiments. Thin-walled hollow microspheres are easy to crack while drying and being used due to the increase in diameter-to-thickness ratio(diameter/wall thickness). In this work, the influence of the PS materials on the quality of thin-walled microspheres was studied, and the mechanism was discussed. The results show that when the oil phase(PS) mass fraction was 4%, the stability of W1/O/W2 composite emulsion particles gradually increased with the increase of oil phase viscosity;when the oil phase mass fraction was not less than 8%, the stability of compound droplets was fine. There is no significant difference in the surface roughness of the corresponding microspheres. The sphericity and wall thickness uniformity of microspheres decreased with the increase of initial oil phase viscosity. In the drying process, the cracking rate of microspheres decreased with the increase of oil phase viscosity. The rate of microsphere cracking decreases as the mechanical properties of the raw material improves. To compensate for the adverse effect of the increase in oil phase viscosity on the sphericity and uniformity of the wall thickness of the microspheres, fluorobenzene(FB) droplets were introduced into the external water phase to reduce the solidification rate.