Migration experiments with expanded polystyrene were performed in one-sided contact with distilled water and 95%(V/V) ethanol water as the food simulants at various temperatures(25, 45 and 65℃) and the styrene migrating to the food simulants was tested from 1 to 240 h. The results show that styrene could hardly be measured in distilled water and the amount of styrene in the 95%(V/V) ethanol water was obviously greater than that of in distilled water. The diffusion coefficients of styrene in expanded polystyrene were 5.08×10-9,1.29×10-8 and 6.78×10-8 cm2/s at various tempera-tures(25,45 and 65℃) and the corresponding activation energy of the migration process was 53.9kJ/mol.%采用单面浸泡的方式，以蒸馏水和体积分数为95%的乙醇为食品模拟液，研究发泡聚苯乙烯（EPS）中苯乙烯（ST）在不同温度（25,45,65℃）和不同浸泡时间（1～240 h）下的迁移情况。结果表明：在蒸馏水食品模拟液中，很难检测到苯乙烯的迁移；在体积分数为95%的乙醇食品模拟液中，苯乙烯的迁移量要明显高于其在蒸馏水中的迁移量；25,45,65℃条件下，EPS中ST在体积分数为95%的乙醇食品模拟液中的扩散系数分别为5.08×10-9,1.29×10-8,6.78×10-8 cm2/s，对应的活化能为53.9kJ/mol。
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