Synthesis of a kaolinite-poly(β-alanine) intercalation compound

A kaolinite-poly(β-alanine) intercalation compound (kaolinite/poly(β-alanine)) was synthesized by in-situ polycondensation of preintercalated β-alanine, which is an initial step toward the extension of the variety of host materials for polymer-clay nanocomposites. β-Alanine was intercalated into kaolinite by a displacement method using kaolinite/ammonium acetate as the intermediate. Zwitterionic β-alanine was ordered in a monolayer arrangement between the layers, which was confirmed by powder XRD, IR and NMR. Although β-alanine was mostly polymerized by thermal treatment of kaolinite/β-alanine at 250°C for 10 h under an N₂ atmosphere, a part of the guest species was decomposed. Kaolinite/poly(β-alanine) had a higher thermal stability than bulk poly(β-alanine), as evidenced by TG-DTA.