Hello everyone. I want to know how to make grow-in-water toys. I have experience using silicone and resin and I have a 3d printer to work with. I already have the matrix for the toy, but I don't really know wich material I must use and how. I can't find any intructions of making it and wikipedia says they are made from a superabsorbent polymer, but doesn't say wich one. My only source says they are maded of polyacrylonitrile, ethylene glycol and glycerol, but -again- doesn't say how to combine them.
Can someone help me or direct me with a link?
Update: I find a new recipe:
"[...] a mixture of sodium polyacrylate, polyvinyl acetate (a polymer used as a binder) and ethylene vinyl acetate (a polymer used to mold the toy into whatever shape it’s supposed to be)."
>>931259
I think they are just regular foam, compressed and coated with a glycerol and ethylene glycol shell (which dissolves in water). I could be thinking of a different one.
>>931318
thanks for the response
>>931318
you're wrong. they shrink again when you dry them out.
>>931433
Any grow-in-water toy that I know shrinks again when it comes out the water, but it takes about one entire day.
>>931307
I was interested in this a while back.
I think EVA plays a key part because higher concentrations of Vinyl/Acetate in an Elastomer will increase water permeability.
I wondered if Silicone might work, it has a water permeability of 1% its volume. Although it isn't as inert as EVA.
