I haven't had that particular beer, but I'd say you probably got a bad six pack. I've never tasted anything plastic-like in any of the ESBs I've tried.
Next: House Dark Mild, ESB, and Best Bitter
Primary: Wheat Dark Mild, English IPA, House Ordinary Bitter
Souring: Brett C Old Ale, '15 Lambic, '14 Lambic, Flemish Red, Flemish Pale, Oud Bruin, Session Kriek
Bottled: Gose, Lichtenhainer, Gruit, Honey Porter, Wit, Kitchen Sink Tripel-ish-thing, Belgian Blond, Oat Dark Mild
Cellar: Brett B Tripel, '11 Lambic, Brett C Barleywine, Quad, Sour Stout, Brett C Bitter, Wild Cider, Wee Heavy, Brett B Red, Brett L Kriek, Bière de Garde