I found this pattern for a reusable sandwich wrapper and it calls for polyurethane laminated fabric that they didn't carry at my Hancock Fabrics. Buying it online seemed like an additional expense that I didn't need to incur, just to make a reusable product. At the same time I had also been fusing plastic bags with an iron, for some strange reason, not really knowing what I would do with the fabric it creates.
It hit me while I was at the fabric store, sew the plastic "fabric" as the interior lining of the sandwich wrapper. I found that I had some scraps of fabric that I could use. It takes about 1/6 of a yard, but you may like them so much you need a new yard for 6 of them, like I apparently do.
You have to enlarge the pattern to 200% which is kind of hard to do, even on a commercial copier beacuse you need 11"x17" paper and then you have to line it up right, so I just cut and pasted some of the pieces together. Then there's the fusing. It is recommended you use the number 2 plastic bags and about 2 layers of a nice clear or plain white bag fused together is the right thickness. So it takes one big bag, not just a grocery bag, to cut all the pieces. My favorite was a large Macy's bag that I cut all the white parts from. Target bags would work well too, but I just don't like the patterns on the inside of my creation. Plus you have to fuse the bag inside out so the ink side fuses on itself, you don't want it touching your sandwich. Place the bag between two sheets of parchment paper, or just regular paper, set the iron on a medium setting (you will have to experiment to get it right though) and iron over the bag, moving the iron constantly.
Zig zag stitch the plastic to the fabric around the edges and continue to sew as the pattern describes. I actually have not tried it yet, but tomorrow it will be in the field.