Sustainable and reversible 3D printing method uses minimal ingredients and steps

https://phys.org/news/2024-08-sustainable-reversible-3d-method-minimal.html

"poly(N-isopropylacrylamide) polymer ink, extruded through needle into calcium chloride salt solution, instantly solidifies since salt ions draw water molecules out of polymer solution... ambient conditions, no: additional steps, specialized equipment, toxic chemicals, heat, pressure... reversible, solids easily dissolved in fresh water recycling ink... printed electrical circuit using this ink mixed with carbon nanotubes, which powered a light bulb, and then circuit was then dissolved back into ink"

Related: Surprising breakthrough in carbon nanotube recycling, paving way for sustainable materials
https://news.rice.edu/news/2025/rice-researchers-unveil-surprising-breakthrough-carbon-nanotube-recycling-paving-way