How can I make a bow out of plastic canvas without the plastic breaking?

I am trying to make a bow from plastic canvas. I took a piece of plastic canvas 6 holes wide by 49 holes long, stitched it with yarn and connected the ends to make a circle. Then I took another piece of plastic canvas 5 holes wide by 23 holes long, stitched it and connected the ends to make a small circle. Holding the smaller circle vertically, and the larger one horizontally, I slipped the smaller one over the larger one to make it look like a bow. The smaller one is supposed to be the knot. My problem is that the plastic canvas on both pieces broke. I am making small boxes from plastic canvas that I have stitched to look like packages and I want to make bows to put on top of the boxes. Does anybody have any ideas on a different way I can make the bows so the canvas does not break? Any help will be greatly appreciated. Thank you!