A game-changing diaper?

Why it is in news?
  • A team at IIT Madras develops a biodegradable, super-absorbent polymer.
What it made of? and problems associated with it.
  • Diapers contain super-absorbing polymers, or SAPs, which can absorb and retain a large quantity of liquid.
  • They are made of synthetic materials that are non-biodegradable.
  • Safe disposal of used diapers is thus becoming a major environmental problem.
Solution by scientists
  • scientists from the Department of Chemistry at the Indian Institute of Technology, Madras have developed a biodegradable super-absorbent polymer using chitosan (a kind of sugar extracted from seafood waste), citric acid and urea.
  •  This super-absorbent has capacity — it can absorb 1,250g of water for each gram of the polymer.
A comparison
  • The researchers used chitosan obtained from seafood waste source, and two easily available sustainable chemicals — citric acid and urea.
  • Water absorbing material from a commercial baby diaper was used for comparison.
  • The materials (chitosan, citric acid and urea) were mixed in a weight ratio of 1:2:2.
  • The mixture was heated in aqueous medium to 100º C in a closed container to form a highly viscous and porous, cross-linked gel denoted as CHCAUR (from chitosan, citric acid and urea).
  • The gel was then dried to remove residual solvent and powdered for further study.
  • It was found that the water absorption capacity of CHCAUR was about eight times more when compared to super absorbing polymers used in commercial diapers.
Other applications
  • It can also find applications in agriculture, especially as a controlled releasing agent of micro- and macro-nutrients to soil.
  • The study also mentions that when applied to soil, CHCAUR was found to decrease water evaporation rate significantly.
  • The research team is now working on similar biodegradable polymers as a substitute for polyurethane and polystyrene packaging materials that do not degrade.
Source
The Hindu
 
Posted by Jawwad Kazi on 5th Aug 2018