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Are there any material that contact with water and expand?

  1. Jan 28, 2014 #1
    Are there any material that contact with water and expand? I can think of sodium polyacrylate, but I can't use it. Thanks.
  2. jcsd
  3. Jan 28, 2014 #2
    Anything that's been dehydrated comes to mind such as dried peas. Just thought of something else but I dont know what its called. It comes in powder form and when water is added it expands to a soggy jelly. You can add it to the soil in plant pots to maintain the moisture level.Try your local plant nursery. I guess there are loads of other things.
  4. Jan 28, 2014 #3
    I think the soggy jelly that you mention is SAP(Super absorbent polymer) which is sodium polyacrylate that I mention, but I can't use it. Basically I need a material that significantly increase in volume when hydrate or being stimulate. Thanks.
  5. Jan 28, 2014 #4
    I'm guessing there are safety issues with SAP. How about dehydrated foodstuffs? If powdered these can probably rehydrate in a short time.
  6. Jan 28, 2014 #5


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  7. Jan 28, 2014 #6


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    There are these polysaccharide powders used for gel permeation chromatography (separation on a molar mass basis) sold under the name Sephadex, they swell 10 or more times in volume on adding water.
  8. Jan 28, 2014 #7
    Thanks for every answers.
  9. Jan 29, 2014 #8


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  10. Jan 29, 2014 #9
    Polyacrylamide and bentonite clays (sodium bentonite in particular). They are pretty swell :)
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