Polyolefin rhymes with:
olefin, olefin, cyrofin, dystrophin, hanafin, olefin, sarafin, serafin, alfin, alphin, buffin, chaffin, chafin, chalfin, coffin, cyrofin, daffin, dauphin, delfin, diffin, duffin, dystrophin, elfin, endorphin, gaffin, giffin, goffin, golphin, griffin, guffin, hanafin, hanifin, hannifin, kniffin, laffin, morfin, murfin, myotrophin, olefin, rofin, ruffin, sarafin, serafin, serfin, superfon, sutfin, sutphin, threadfin, tiffin, woodfin
Polyolefin sounds like:
pavlovian, philbin, philippine, philippino, phillabaum, phillipine, playpen, plebeian, plybon, polyphony