Layered calcium phenylphosphonate: a hybrid material for a new generation of nanofillers

Abstract

The use of nanosheets of layered calcium phenylphosphonate as a filler in a polymeric matrix was investigated. Layered calcium phenylphosphonate (CaPhP), with chemical formula CaC6H5PO3∙2H2O, is a hybrid organic–inorganic material that exhibits a hydrophobic character due to the presence of phenyl groups on the surface of the layers. In this paper, various CaPhP synthesis methods were studied with the aim of obtaining a product most suitable for its subsequent exfoliation. The liquid-based approach was used for the exfoliation. It was found that the most promising technique for the exfoliation of CaPhP in an amount sufficient for incorporation into polymers involved using propan-2-ol with a strong shear force generated in a high-shear disperser. The filler was tested both in its unexfoliated and exfoliated forms for the preparation of polymer composites, for which a low molecular weight epoxy resin based on bisphenol A was used as a polymer matrix. The prepared samples were characterized by powder X-ray diffraction, atomic force microscopy, optical and scanning electron microscopy, and dynamic mechanical analysis. Flammability and gas permeation tests were also performed. The addition of the nanofiller was found to influence the composite properties – the exfoliated particles were found to have a higher impact on the properties of the prepared composites than the unexfoliated particles of the same loading

Synthesis and Exfoliation of Calcium Organophosphonates for Tailoring Rheological Properties of Sodium Alginate Solutions: A Path toward Polysaccharide-Based Bioink

“…The synthesis of mixed calcium phosphonate–phosphate follows the same route as preparation of CaPhP which has been described in our previous works. , Whereas for obtaining pure CaPhP, keeping the pH > 9 is the only necessary condition, for material with combined phosphonate and phosphate groups there are other important factors influencing the properties of the final product. The molar ratio of the reacting acids determines not only the composition but also the basal spacing of the final product.…”

“…The synthesis and exfoliation of CaPhP, as well as its use for preparation of polymer–inorganic nanocomposites, were described in our previous work. 41 To increase possible interactions and compatibility with water-based systems, such as hydrogels, new material was synthesized where part of the phenyl groups was replaced by phosphate, followed by characterization, exfoliation, and optimization of the nanocomposites with NaAlg solution for 3D printing.…”

“…An appropriate solvent that possesses good compatibility with the material submitted to exfoliation can act as an exfoliating as well as a stabilizing agent for nanoplatelets formed during the process. 44 The suitability of the combination of material and solvent can be tested by the simple procedure described by Kopecká et al, 41 in which a small amount of material in solvent is treated by ultrasound for 1 h. The stability of the obtained dispersion is observed and the presence of NPs is verified by Tyndall scattering. 45 In the present work, four solvents were tested: water, isopropyl alcohol, ethylene glycol, and glycerol.…”

Advanced hybrid nanomaterials

“…Exfoliated nanosheets of layered calcium phenylphosphonate assisted by solvent were used in "Layered calcium phenylphosphonate: a hybrid material for a new generation of nanofillers" to promote the mechanical properties and improve the barrier effect for applications such as fire retardancy and gas permeation in a low molecular weight epoxy resin [28].…”