I use 100% cotton most of the time. But, 32 years ago, my mother made me a blanket with a single piece of lavender polyester for the top and a single piece of navy polyester for the backing. She put polyester batting inside and tied it with yarn. 32 years late, that quilt looks the exact same as it did the day she gave it to me. You just can't kill polyester! It's not the prettiest quilt, but it has lasted. She made a double wedding ring out of cotton for my wedding and it is in tatters. She made my daughter a Holly Hobby out of cotton and it is in tatters. So who knows? I love them all, but I can only use the polyester blanket.