Dacron or taffeta from fabric store. May be the same stuff.
Here's a hint. Take a piece a foot or so square. Iron it smooth. Using a light pencil and straight edge, draw out a grid using whatever size hinges you want; 1/2" by 1" or whatever.
Next, take a striping brush and run a narrow line of dope over the pencil lines. Let dry and cut on a cutting board using a straight edge and sharp razor. I like the double edged blades broken in half. They seem to work well on the fabric. A number 11 blade tends to snag the threads. Or better use a fabric cutting wheel.
You now have nice uniform hinges and the edges wont fray when you handle them.