Spray the stain with amyl acetate. Test colored fabrics to be sure dye will not bleed. If sponging the stain does not remove the plastic, cover the stain with a pad moistened with solvent and leave it until the plastic has softened. Then sponge with solvent until all traces of plastic have been removed.
Always read the care label before trying any stain removal method. Do not use any products or procedures prohibited by the care label.
Be careful any time a commercial product or combination of cleaning supplies are used.
Always pretest each cleaning agent on an inconspicuous area first to determine colorfastness.
Be sure to store and dispose of products/cans/containers as recommended. Keep out of reach of children.
When using caustic or commercial cleaning solutions, be certain to provide for adequate ventilation.