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For the first time in the literature, a shear enhanced process (or dynamic filtration) called Rotating and Vibrating Filtration (RVF technology) was investigated for wine clarification. The impact of membrane material (hydrophilic PES and hydrophobic PTFE with a cutoff of 0.2 mm), wine composition (filtered wine, FW and Crude simulated wine, CSW) and operating conditions (transmembrane pressure and rotational frequency) are reported. RVF module is characterized by a complex hydrodynamic generated by a 3 flat blades impeller in a confined cell. An additional driving force is generated by rotational frequency and is taken into account to calculate the apparent and real permeabilities. Filtered wine (FW) generates an irreversible fouling whatever hydrophilic or hydrophobic membrane material. Even if PES membranes performances (Lp 0 final ¼1670 L h À 1 m À 2 bar À 1) were higher compared to those of PTFE membranes (Lp 0 final ¼170 L h À 1 m À 2 bar À 1), nor rotational frequency (mechanical stress), nor water rinsing did significantly remove or reduce fouling but, on the contrary, favors its compression and membrane plugging. Crude simulated wine (CSW) includes pectins, tannins and mannoproteins. CSW filtration runs demonstrated a mechanical impact onto fouling reduction with PES and PTFE membranes. However mechanical efficiency is moderated by material properties which generated irreversible fouling with different magnitudes. PTFE and PES permeability gains stand for þ 34% and þ 300% respectively. Finally, a "critical frequency" is defined above which a permeability increase and hydraulic resistance reduction is induced by rotational frequency (22 and 30 Hz for PES and PTFE membranes respectively).

Ion-track nanotechnologies for the formation of micro-and nanostructures from various materials, in particular, metals and alloys as nanowires and microtubes, with the use of polymer track membranes as template matrices have received increasing attention in the last few years [1,2]. Track membranes have also been used as templates for the synthesis of nanopolymeric materials, which, in particular, possess membrane properties [3,4]. However, research in this area of iontrack technology is in its infancy and many kinetic and structural features of the formation of polymeric microand nanostructures on polymer templates, as well as the physicochemical and other properties of micro-and nanopolymers synthesized, are still poorly known. Therefore, systematic studies aimed at determining the general features of the polymerization of structurally different monomers on polymer templates, as well as studies on the structure and properties of micro-and nanopolymeric materials thus prepared, are of undoubted scientific and practical interest for the development of this area of ion-track nanotechnology.In this paper, we report preliminary results concerning the polymerization of monomers, such as pyrrole and N -methylpyrrole, on poly(ethylene terephthalate) (PET) membranes with micron-sized pores (1.2-5 µ m). The structure and properties of nanopolymeric membranes synthesized from these monomers were also studied. Note that conducting nanopolymeric materials can be prepared from polypyrrole and its derivatives.These materials can find various applications in technology and medicine, for example, as biosensors [5][6][7]. EXPERIMENTALTrack membranes based on PET films of 10-12 µ m in thickness with various initial parameters (pore diameter d , pore length l , and porosity δ ) (Table 1) were taken as templates. The PET track membranes were obtained in the Flerov Laboratory of Nuclear Reactions at the Joint Institute for Nuclear Research (Dubna). The polymer films were irradiated with accelerated multicharged ions of xenon with an energy of 1 MeV/nucleon on a U-400 cyclotron (fluence of 2 × 10 8 cm -2 ); next, the films were irradiated with UV light at λ ≥ 300 nm in air for 60 min at room temperature. Thereafter, the films were subjected to alkali etching in 3 M NaOH at 338 K for 30 min [8,9].Abstract -The oxidative polymerization of pyrrole and N -methylpyrrole with the use of template synthesis on poly(ethylene terephthalate) (PET) track membranes was studied. By scanning electron microscopy (SEM), it was found that a polymer film was formed on the surface of membranes and on the walls of membrane pores. The rates of polymerization on the surface of membranes and pore walls, as well as the yield and structure of the polymer film, depend on the membrane parameters (pore length and diameter and membrane porosity), the chemical structure of the monomer, the diffusion of polymerized solutions through template pores, and the temperature.

The results of a structural study of conducting polymer coatings deposited onto poly(ethylene terephthalate) (PET) track membranes by template synthesis are reported. The following aspects of the quality of polymer coatings were studied: the ratio between film and granular polymers, the polymer distribution over the surface of track membranes, and the thickness of polymer layers on the opposite sides of track membranes. The fraction of granular polypyrrole (PPy) on the surface and in the pores of a film increased with pore diameter. A decrease in the polymerization temperature decreased the amount of granular PPy on the surface of membranes, whereas the effect of granular PPy on the water permeability of track membranes remained unchanged. A more homogeneous distribution of PPy over the surface of track membranes can be obtained by density equalization of reacting solutions; however, the fraction of granular PPy on the membrane surface increased in this case. It was found that polymer coatings on the two sides of the surface of a membrane template had different thicknesses. Poly( N -methylpyrrole) completely covered only one side of a track membrane facing a monomer solution.