用超临界CO_2对经~(60)Co γ-射线辐照的PMMA进行发泡,制得了微孔PMMA泡沫.研究了辐照剂量、饱和压力和温度对所得泡沫的孔形貌和结构的影响.结果表明,所得泡沫都具有封闭的球形泡孔结构,泡孔尺寸比较均一;经~(60)Co γ-射线辐照的样品的孔密度均比未经辐照的高;随饱和压力的增大,平均孔径减小,孔密度增大;饱和温度对所得泡沫的孔径和孔密度的影响比较复杂.“,”Microcellular PMMA foams were prepared by supercritical CO_2 foaming of ~(60)Co γ-ray irradiated PMMA. The effects of radiation dose, saturation pressure and temperature on the cell morphology and structure of the obtained foams were studied. The results showed that the foams possessed spherically closed cell structure with uniform cell size; the γ-ray irradiated samples had a higher cell density than those unirradiated, the average cell size decreased and the cell density increased with an increase of saturation pressure, and the saturation temperature had a complicated effect on the cell size and cell density of the obtained foams.