|MadSci Network: Engineering|
Sorry, I don't know the details of the method by which cellulose sponges are made, other than they are made by regeneration of cellulose from a derivative (presumably cellulose xanthate), and that the holes are made by carring out the regeneration in the presence of coarse sodium sulfate which is then leached out by water. I'm not familiar with the term "Pop up". Moderator's note: Also, sponges are manufactured in huge blocks the size of a Volkswagen, then cut down to size. You should try the following resources for more information: Patent search for O-Celo or cellulose sponge Literature search for Gerard Murray, inventor of cellulose sponge in 1946-ish Contact major manufacturers like 3M or DuPont for more information Good luck!
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