I don’t really have any idea of these would work or if it even makes sense as a sponge. BUT…its a neat idea for recycling or upcycling all those awful plastic bags that everyone has lying around.
For 1 sponge you will need about 10 plastic shopping bags (medium size), fold them, cut into loops, then connect them and make your “plastic yarn” and begin crocheting using some simple pattern for making flower- make a ring from 5 chains and then you can double your stitches as often as you like.
Here’s the article
Plastic bags into dishwashing sponge