Firstly, it is a polymer -this kind of polymer can absorb liquid so much! It can absorb about 200-2000 times weight purified water and turn to be water gel. But it will be about 50 times in the saline solution.
It can be used in Hygienic products (like diapers) as an absorbent material and industry production (like waterproof ,anti-flood bag and so on). Another side, the water gel can provide plants water. Actually, this kind of absorbent crystal can help plant keeping water and increase yield in the arid season. ( details... )
It depends on the application. For example, the absorbent rate is an important item in hygienic products but the situation will be changed for agriculture application.
There will be a big difference in a different application. But it usually can be USD 1.8-3.5 per kilogram.
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