Abstract
2-Ethylhexyl 2, 3-dihyroxypropyl phthalate [GOP (o) ] and its isomers [isophthalate (GOP (iso) ) and terephthalate (GOP (tere) )] were prepared to examine the synergetic effects on the thermal stabilization of poly (vinylchloride) with unpoisonous synergetic metal soaps (Zn stearate/Ca stearate).
1) These phthalates slowed down the abrupt discoloration (zinc burning) of poly (vinyl chloride) films and showed marked synergetic effects. The order of masking ability was as follows :
GOP (o) >GOP (iso) ≈GOP (tere)
2) The best synergetic effect of GOP (o) in the three isomers shoud be due to the masking effect of their vicinal hydroxyl groups and -COO- segments near the hydroxyl groups.
