social design project 2 in progress

Been working on refining my idea and prototyping. I was trying to figure out a way to tie in the idea of trash into the overall form of the bracelet (starting there, will expand out), and I hit on the idea of using a plastic bag as the form. I did a quick prototype out of a bag from a roll of vellum.



Overall, I think it conveys the idea, but I want a more crinkly look- like you get from the cheap grocery bags. Those were too wide, but I found a couple bags that I thought would work. I decided to fill them with alginate so that they would hold the right volume and form for when I mold them.
Here are the 2 bags I used all alginated up.

Not sure which one will work better yet, but I'm planning to do the silicone mold Monday and go from there. Potential Casting materials so far are: slipcasting plastic (translucent), a flexible rubber, I'd also like something that is totally green. The plastic references the actual bags, the rubber would be sanitary and easy to clean, so I'd like something that is completely biodegradable as well- I'm thinking maybe corn starch?