以ICF实验塑料靶丸保气的需求为背景,研究了水蒸气在低压等离子体聚合碳氢(CH)膜、聚乙烯醇(PVA)膜、聚苯乙烯( PS)膜中的扩散渗透行为.根据实验数据,算出在40℃ 90%相对湿度下,水蒸气在三种样品膜中的渗透系数分别为1.906×10^-13,5.950×10^-15,3.342×10^-14 mol·m/(m²·s·Pa),并借助多层复合膜模型的近似算法,算出在40 ℃ 90%相对湿度的外界环境下,类似多层塑料微球结构的三层复合膜中,PVA阻气层所处环境的相对湿度为53.06%,推导出PVA所处环境的相对湿度与外层CH层厚度的关系式.研究表明:CH烧蚀层越厚,PVA所处环境的相对湿度越小,保气性能越好.

Considering gases retention in plastic microsphere in ICF experiment,the diffusion and permeation behavior of water vapor in hydrocarbon (CH) film,polyvinyl alcohol (PVA) film and polystyrene (PS) film at 40 ℃ 90% relative humidity was studied in this paper. On the basis of experimental data, the permeatibility coefficients of water vapor in three films were worked out,which are separately 1.907×10^-13,5.950×10^-15,3.342×10^-15 mol·m/(m²·s·Pa).And the relative humidity of middle layer (PVA) of 53.06% in three-layer structure, which is analogous to multilayer plastic microsphere's, under 40 ℃ 90% relative humidity environmental condition was figured out using an approximate model of multilayer packaging structure. Moreover,the relationship between thickness of CH film and relative humidity of middle layer (PVA) was deduced, that is, the thicker CH film is,the lower relative humidity of PVA is,and the better gas barrier property is.