Effect of Simulated Acid Rain on Release of Plasticizer in PVC Film

One kind of PVC was selected to investigate the effect of simulated acid rain on the release of plasticizer in the film.The results showed that the plasticizer was di-(2-ethylhexyl) phthalate(DEHP) and the released material mainly was DEHP in PVC film under simulated acid rain treatment.When the pH value of acid rain solution was 6.5 and 5.6,the released amount of DEHP reached a peak at 30 day treatment(about 2.66% and 2.38%).The released amount of DEHP was moderate solutions with pH 7.0 and 2.5(1.46% and 1.52% within 30 days).The reducing rates of DEHP remained the least at pH 3.0 and 4.0 solutions(about 1.33% and 1.22% within 30 days).DEHP was easy to disperse and degrade in weak acid solutions and PVC was prone to have crevice on its surface.The solutions of pH 5.6 and 6.5 made DEHP easy to release from PVC films.