Polyester rhymes with:
amvestor, bester, brester, chester, ester, esther, fester, hester, investor, ivester, jester, kester, leicester, lester, mclester, mester, mestre, molester, nester, nestor, pester, questar, requester, rester, semester, sequester, silvester, sylvester, sylvestre, tester, testor, trester, trimester, vestar, vester, westar, wester
Polyester sounds like:
pelster, pilaster, plaster, plasterer, policastro, pollster, polster