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Electrically conducting or electroresponsive smart materials derived from newly synthesized and characterized 1D/2D (nano)particles of zinc phenylphosphates are reported.

Ab initio molecular orbital calculations at the MP2/6-31G level of theory have been used to study the molecular geometry, electronic structure, and the thermal stability of six-membered phosphazene and heterophosphazene rings. The studies included the phosphazene ring [NPCl(2)](3), the carbophosphazene ring [(NCCl)(NPCl(2))(2)], and three thionylphosphazene rings [(NSOX)(NPCl(2))(2)] (X = F, Cl) and [(NSOF)(NPF(2))(2)] and their cations [(NPCl)(NPCl(2))(2)](+), [(NC)(NPCl(2))(2)](+), and [(NSO)(NPY(2))(2)](+) (Y = F, Cl). The ring skeleton of the phosphazene ring, the carbophosphazene ring and of all cation rings adopt a planar conformation; the ring skeletons of the thionylphosphazene rings adopt an envelope conformation. The valence electron charge density of the molecules indicates strong charge separations along their skeleton and is in agreement with Dewar's island delocalization model. The electrostatic potential in the vicinity of the neutral heterophosphazene rings which results from their electronic structure, and the position of the HOMO indicate that a heterolytic cleavage of a ligand and the opening of the ring involving a reaction with a electrophilic cation will most likely occur at the nitrogen atoms close to the heteroatom. The thermal stability of the phosphazene ring with respect to a cleavage of chlorine from phosphorus and the thermal stability of the heterophosphazene rings with respect to the cleavage of the halogen ligand bonded to the heteroatom were studied with several model reactions. Most of the reactions are exothermic. A comparison of isodesmic reactions shows that the thionylphosphazenes molecules are the least thermally stable rings with respect to ionization and that the carbophosphazene molecules are the most thermally stable rings with respect to ionization. The energy gains during the ionization reaction of the rings correlate well with the conformational changes which occur during the reactions.

The reaction of boehmite with diethyl phosphoric acid generated in situ in a boiling water solution of triethyl phosphate has been studied in detail. Two kinds of solid products have been isolated and characterized by elemental and XPS analysis, in addition to XRD, TGA, FT-IR, SEM, and MAS NMR techniques. One of them precipitates from the reaction mixture in the form of fibers containing needlelike hexagonal crystals with the unit-cell parameters a = 21.105(4) Å and c = 9.112(2) Å (V = 3515(1) Å3). The crystalline structure comprises hexagonally packed catena Al[OP(O)(OC2H5)2]3 chains. The other ones form a colloidal dispersion of spherical nanoparticles that consist of a boehmite core covered by aluminodiethylphosphate chains. The NMR studies of the reaction mixture indicate that water soluble aluminophosphate species are also formed in the systems studied. These species are suggested to act as nutrients for the growth of aluminophosphate structures. Colloidal particles and fibers have been included into the polyurethane matrix by in situ polyaddition. The SEM images of the composites surface cross-section shows that spherical nanoparticles are homogeneously distributed in the polymers, whereas fibers tend to agglomerate. Some mechanical reinforcement of the surface of polyurethanes has been accomplished as indicated by the abrasive wear test and AFM images.

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Boehmite particles modified with organic ligands were prepared through the reaction of boehmite with acrylic acid or diethylphosphoric acid (formed in situ from triethyl phosphate). The chemical structures of these particles were determined, and it was shown that they formed stable aqueous dispersions with a particle size lower than 200 nm (average diameter ¼ 40-100 nm, depending on the method of modification) for more than 90% of the population. These nanoparticle dispersions were mixed with carboxylated styrene-butadiene latex, and after water evaporation, homogeneous composites were obtained when the modifier concentration was in the range of 0.5-3 wt %. The mechanical properties of the composites were improved with respect to those of the unmodified rubber (tensile strength up to 200% and elongation at break up to 40%). The modifiers also improved some mechanical properties of rubbers cured with sulfur/N-cyclohexylbenzothiazole-2-sulfenamide/ZnO/stearic acid or ZnO/stearic acid systems.

Thermal properties of coordination polymers with formula Al[O2P(OR)2]3 [R = Me, Et, nPr, iPr, nBu, CH2CH(Et)(CH2)3CH3 or Ph] are reported.

This work investigates the potential application of various sterilization methods for microorganism inactivation on the thermoplastic starch blend surface. The influence of the e-beam and UV radiation, ethanol, isopropanol and microwave autoclave on structural and packaging properties were studied. All the applied methods were successful in the inactivation of yeast and molds, however only the e-beam radiation was able to remove the bacterial microflora. The FTIR analysis revealed no significant changes in the polymer structure, nevertheless, a deterioration of the mechanical properties of the blend was observed. The least invasive method was the UV radiation which did not affect the mechanical parameters and additionally improved the barrier properties of the tested material. Moreover, it was proved that during the e-beam radiation the chain scission and cross-linking occurred. The non-irradiated and irradiated samples were subjected to the enzymatic degradation studies performed in the presence of amylase. The results indicated that irradiation accelerated the decomposition of material, which was confirmed by the measurements of weight loss, and mass of glucose and starch released to the solution in the course of biodegradation, as well as the FTIR and thermal analysis.