3-(Methylamino)propylamine as a templating agent in the synthesis of phosphate-based inorganic polymers

Abstract

3-(Methylamino)propylamine (MPA) was studied as a structuredirecting agent (template) in the synthesis of open-framework phosphate-based materials. The influence of temperature, mole ratio of reactants, crystallization time and presence of fluoride ions on the crystallization of aluminophosphate, transition metal-substituted aluminophosphate (transition metal -Mn(II), Cr(III) and Co(II)) and zincophosphate was also investigated. MPA exhibited a templating role and in all the as-synthesized crystalline products, it is entrapped in an inorganic lattice interacting with the framework via hydrogen or/and electrostatic interactions. According to detailed thermal analysis, the type of interactions seems to be crucial for the thermal behavior of MPA and for the thermal stability of the organic-inorganic crystal system. Structural analysis suggested that the formed crystalline structures had no mutual structural analogy. This indicates that the precise role of the organic (guest) component in nucleation process for the open-framework phosphates (host) is very complex as is the nucleation process itself. Copyright 2013 (CC) SCS.