Last year I got a heap of vintage millinery items, including two strands of white cellophane-braid. Braided cellophane was popular for hats between the 1920s-50s. Today it´s nearly impossible to find.
Unfortunately the material is delicate and don´t get along with sunlight or dampness. Accordingly to this, both strands where in a poor condition, parts of them half rotten. However, I tried to make a hat in a 1920s style, to practice the handling of difficult material. I had to damp it, keep it wet in a cloth and sew it carefull with needle and thread over a hat block, without ripping the braid or dissolve it. After that I stiffed it with starch and millinery wire at the edge.
To my own astonishment it worked! The hat may be a little eccentric and every touch makes a crackling sound like withered leaves (no wonder, cellophane is made of cellulose), but it is wearable at all!