HOW DOES POLYFILL INSULATION WORK? Polyfill for outerwear has historically been an effective insulator, partly because of the fibers themselves, plus the fibers ability to trap air (up to 97% of its volume). Technical polyester fibers will produce a soft hand feel and durable garment.Click to see full answer. Similarly, you may ask, is stuffing a good insulator? Clothing and Garments Because of its resistance to solvents and its low thermal conductivity, fiberfill stuffing is often used as insulation for clothing garments. The product is light so it does not weigh down garments, even while it provides a lot of insulation.Secondly, what is the best insulating fabric? Wool. Wool is a traditional winter fabric that is used in sweaters, clothing linings and accessories to provide insulation. Down. Down, the soft, fluffy feathers from ducks and geese, is another natural insulating material used in garments and home goods to maintain warmth. Polyester Fleece. Polyester Fiberfill. Accordingly, how do you use fiberfill? How to Stuff a Pillow With No Lumps Turn the pillow fabric right side out. Pull out a small handful of polyester fiberfill. Tease it apart into a fluffy cloud to eliminate clumping. Push the fiberfill into the pillow, shoving it into the far corners of the pilow. What is polyfill made of?A synthetic material used as cushioning in pillows and bedding, poly-fill is soft, durable, extremely fluffy, and widely used in the mattress industry. Made from polyester, the material is commonly referred to as polyester fiber, fiberfill, or, simply, stuffing.