Long-alkyl chain functionalized poly(propylene imine) dendrimer, poly(ethylene imine) hyperbranched polymer, and beta-cyclodextrin derivatives, which are completely insoluble in water, have the property of encapsulating organic pollutants from water. Ceramic porous filters can be impregnated with these compounds resulting in hybrid organic/ inorganic filter modules. These hybrid filter modules were tested for the effective purification of water, by continuous filtration experiments, employing a variety of water pollutants. It has been established that polycyclic aromatic hydrocarbons (PAHs) can be removed very efficiently (more than 95%), and final concentrations of several ppb (microg/ L) are easily obtained. Representatives of the pollutant group of trihalogen methanes (THMs), monoaromatic hydrocarbons (BTX), and pesticides (simazine) can also be removed (>80%), although the filters are saturated considerably faster in these cases.

A series of poly(propylene imine) dendrimers functionalized with long aliphatic chains has been prepared and characterized. The property of these dendrimers to encapsulate polycyclic aromatic hydrocarbons from water down to a few ppb level has been established. The inclusion formation constants are orders of magnitude higher than those reported for activated carbon (from 1.4 × 104 to 3.4 × 105 M-1) or cyclodextrins (10−103 M-1) while they are comparable to those of cyclodextrin polymers (from 1 × 108 to 5 × 109). Furthermore, the loading capacities depend on polycyclic aromatic compounds and the type of alkylated dendrimeric derivatives, that is, 6−19 mg/g for fluoanthrene, 44−67 mg/g for phenanthrene, and 34−57 mg/g for pyrene. Regeneration is also feasible using nonpolar solvents.

Triethoxysilyl-functionalized poly(propylene imine) (DAB32) dendrimer and poly(ethylene imine) (PEI5) hyperbranched polymer were conveniently prepared in chloroform and were subsequently allowed to impregnate porous ceramic filters. Following hydrolysis of triethoxysilyl moieties to Si−OH, polycondensation occurred affording networks containing Si−O−Si bridges with simultaneous formation of Si−O−M bridges resulting from the interaction of Si−OH with M−OH of the ceramic surface. In this manner, covalent binding of the organosilicon dendritic polymers is achieved at the ceramic surface. These porous ceramic filters, impregnated with organosilicon dendritic polymers, were employed for water purification. The concentration of polycyclic aromatic compounds in water was reduced to the level of a few ppb by continuous filtration of contaminated water through these filters. The filters loaded with pollutants were effectively regenerated by treatment with acetonitrile.

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A series of hyperbranched polymers functionalized with long aliphatic chains has been prepared and characterized. The property of films prepared from these polymers to encapsulate lipophilic polyaromatic pollutants dissolved in water has been established. The level of pyrene and fluoranthene remaining in water after treatment ranged from 1 to 30 ppb for most of the hyperbranched polymers, while for the relatively more water-soluble phenanthrene a final concentration of about 50 to 70 ppb could be attained. The inclusion formation constants determined for the polycyclic aromatics were 2.0 ϫ 10 8 -6.3 ϫ 10 6 M Ϫ1 for pyrene, 1.2 ϫ 10 7 -1.6 ϫ 10 6 M Ϫ1 for fluoranthene, and 3.8 ϫ 10 6 -4 ϫ 10 5 M Ϫ1 for phenanthrene. The loading capacities depend on the nature of the polycyclic aromatic compounds and the chemical structure of the parent hyperbranched polymers, ranging from 6 to 31 mg/g of polymer for fluoranthene, 15-54 mg/g for phenanthrene, and 6 -35 mg/g for pyrene.Regeneration of the absorbing films was achieved by their treatment with acetonitrile.

This work is investigating the chemical grafting on Ti surface of a polymer/calcium phosphate coating of improved adhesion for enhanced bioactivity. For this purpose, a whole new methodology was developed based on covalently attaching a hyperbranched poly(ethylene imine) layer on Ti surface able to promote calcium phosphate formation in a next deposition stage. This was achieved through an intermediate surface silanization step. The research included optimization both of the reaction conditions for covalently grafting the intermediate organosilicon and the subsequent hyperbranched poly(ethylene imine) layers, as well as of the conditions for the mechanical and chemical pretreatment of Ti surface before coating. The reaction steps were monitored employing FTIR and XPS analyses, whereas the surface morphology and structure of the successive coating layers were studied by SEM combined with EDS. The analysis confirmed the successful grafting of the hybrid layer which demonstrated very good ability for hydroxyapatite growth in simulated body fluid.

A series of N,N-di(2-hydroxyethyl)-N-methyl-N-alkylammonium bromides (alkyl chain from dodecyl to octadecyl) was synthesized and characterized. Its thermotropic liquid-crystal behaviour was studied by differential scanning calorimetry, polarizing optical microscopy, infrared spectroscopy and X-ray diffraction. Two smectic phases were identified, an ordered smectic T and a disordered smectic A phase. Both phases result from an alternate periodic stacking of polar sublayers of ionic head groups and apolar sublayers of alkyl chains in a disordered conformation. In the low-temperature smectic T phase, the ionic head groups are arranged inside the polar sublayers in a particularly dense fashion, a tetragonal crystal lattice. In the high-temperature smectic A phase, the ionic head groups are arranged in a disordered fashion with normal packing density.