Surface properties of calcium and magnesium oxide nanopowders grafted with unsaturated carboxylic acids studied with inverse gas chromatography.
Inverse gas chromatography (IGC) was applied at infinite dilution to evaluate the surface properties of calcium and magnesium oxide nanoparticles and the effect of surface grafted unsaturated carboxylic acid on the nanopowder donor-acceptor characteristics. The dispersive components (γ(s)(D)) of the free energy of the nanopowders were determined by Gray's method, whereas their tendency to undergo specific interactions was estimated based on the electron donor-acceptor approach presented by Papirer. The calcium and magnesium oxide nanoparticles exhibited high surface energies (79 mJ/m² and 74 mJ/m², respectively). Modification of nanopowders with unsaturated carboxylic acids decreased their specific adsorption energy. The lowest value of γ(s)(D) was determined for nanopowders grafted with undecylenic acid, approximately 55 mJ/m². The specific interactions were characterised by the molar free energy (ΔG(A)(SP)) and molar enthalpy (ΔH(A)(SP)) of adsorption as well as the donor and acceptor interaction parameters (K(A), K(D)).
Institute of Polymer and Dye Technology, Technical University of Lodz, Stefanowskiego Street 12/16, 90-924 Lodz, Poland. magdalena.maciejewska@p.lodz.pl
Magdalena
M
Maciejewska
Alicja
A
Krzywania-Kaliszewska
Marian
M
Zaborski
D000327:Adsorption; D017610:Calcium Compounds / Q000737:chemistry*; D002264:Carboxylic Acids / Q000737:chemistry*; D002849:Chromatography, Gas / Q000379:methods*; D008277:Magnesium Oxide / Q000737:chemistry*; D053761:Nanocomposites / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D011208:Powders / Q000737:chemistry; D013499:Surface Properties; D013816:Thermodynamics
D017610:Calcium Compounds; D002264:Carboxylic Acids; D010087:Oxides; D011208:Powders; D008277:Magnesium Oxide; C016538:lime