Intercalation of ε-caprolactam Ions into Inorganic Hosts

Abstract

The intercalation reaction of ε-caprolactam anion (ε–CL-) into hydrotalcite heated up to 500 °C to expel in its double hydroxide gallery and also that of ε-caprolactam cation (ε–CL+) into mica were successfully performed in their aqueous solutions. The intercalation reaction of ε–CL- into 500 °C heated hydrotalcite was completed within 1 h at 60 °C, and the resultant intercalation compound had the interlayer spacing of 0.77 nm. The intercalation of ε–CL+ into mica, on the other hand, proceeded rather slowly in two steps, which was due to the presence of two species, Na+ and hydrated Na+ in the mica gallery, and gave the intercalation compound with the interlayer spacing of 1.47 nm.

Inorganic nanolayers: structure, preparation, and biomedical applications

“…2,18 This is a very useful method, especially for the intercalation of organic molecules, and many different anions have been successfully incorporated in LDHs, such as caprolactam, organic chromospheres, dyes, surfactants, and metal complex anions, and this is even a very useful method for the intercalation of nonionized species, eg, sugar molecules like pentoses. [29][30][31][32][33] The whole process of rehydration should be carried out under an inert nitrogen atmosphere.…”