Figure 2From: New photostabilizers for polystyrene based on 2,3-dihydro-(5-mercapto-1,3,4-oxadiazol-2-yl)-phenyl-2-(substituted)-1,3,4-oxazepine- 4,7-dione compounds The relationship between the hydroxyl index and irradiation time for PS films (40 μm thickness). Containing different additives concentration of additives are fixed at 0.5% by weight.Back to article page