Locking organic solvents by crystallization-induced polymer network

Organogels that lock organic solvents within a polymer network shows promising applications in ice-phobicity, anti-biofouling, conserving cultural heritage etc. However, the synthesis of organogels by versatile and cost-effective methods still remain challenging. Here, we introduce a novel and economical approach to organogel preparation via crystallization-induced polymer precipitation, which involves the straightforward blending of carbonyl contained polymer, nano Ca(OH)₂, and excess ethyl acetate (EA). During the formation, nano Ca(OH)₂ reacts with EA to produce ethanol and calcium acetate, in which Ca²⁺ ionically bonds with carbonyl of polymer. Due to the low solubility in EA and ethanol, calcium acetate initiates crystallization. The interaction between Ca(CH₃COO)₂ and polymer induces the separation of polymer from the solvent, thereby forming a network that locks the surplus EA and ethanol. More importantly, the organogel is capable not only of encapsulating 12 organic solvents within its precursor but also of effectively removing various aged polymeric coatings from wall paintings without leaving residues. This innovative organogel system marks a significant forward in the realm of organogel with applications in conservation and surface engineering.