Linear and ring polymers in confined geometries

A short overview of the theoretical and experimental works on the polymer-colloid mixtures is given. The behaviour of a dilute solution of linear and ring polymers in confined geometries like slit of two parallel walls or in the solution of mesoscopic colloidal particles of big size with different adsorbing or repelling properties in respect to polymers is discussed. Besides, we consider the massive field theory approach in fixed space dimensions d = 3 for the investigation of the interaction between long flexible polymers and mesoscopic colloidal particles of big size and for the calculation of the correspondent depletion interaction potentials and the depletion forces between confining walls. The presented results indicate the interesting and nontrivial behavior of linear and ring polymers in confined geometries and give possibility better to understand the complexity of physical effects arising from confinement and chain topology which plays a significant role in the shaping of individual chromosomes and in the process of their segregation, especially in the case of elongated bacterial cells. The possibility of using linear and ring polymers for production of new types of nano- and micro-electromechanical devices is analyzed

Linear and ring polymers in confined geometries

A short overview of the theoretical and experimental works on the polymer-colloid mixtures is given. The behaviour of a dilute solution of linear and ring polymers in confined geometries like slit of two parallel walls or in the solution of mesoscopic colloidal particles of big size with different adsorbing or repelling properties in respect to polymers is discussed. Besides, we consider the massive field theory approach in fixed space dimensions d = 3 for the investigation of the interaction between long flexible polymers and mesoscopic colloidal particles of big size and for the calculation of the correspondent depletion interaction potentials and the depletion forces between confining walls. The presented results indicate the interesting and nontrivial behavior of linear and ring polymers in confined geometries and give possibility better to understand the complexity of physical effects arising from confinement and chain topology which plays a significant role in the shaping of individual chromosomes and in the process of their segregation, especially in the case of elongated bacterial cells. The possibility of using linear and ring polymers for production of new types of nano- and micro-electromechanical devices is analyzed

Dicyanovinyl End-Capped 9,10-Bis (Phenylethynyl) Anthracenes for Organic Solar Cells

A series of 9,10-bis(phenylethynyl)anthracene dicyanovinyl end-capped derivatives have been used in bulk heterojunction (BHJ) photovoltaic cells prepared by the solution process. The compounds were excessively decorated with moieties enhancing solubility to avoid spontaneous crystallisations in the blends. The topology of the dyes is of the acceptor-donor-acceptor (A-D-A) type. The quantum chemical calculations were done at the B3LYP/6-31G(d) level of theory and HOMO-LUMO levels were calculated. The solar cells’ configuration was as follows: ITO/PEDOT:PSS/P3HT(P3OT)dyes/Al and parameters characterising them, open-circuit voltage (Voc), short-circuit current density (Jsc), fill factor (FF) and power conversion efficiency (PCE) are presented. Anthracene based A-D-A molecules showed photovoltaic activity with an average power conversion efficiencies (PCE) of 2.7%

Organic light emitting diodes (OLED) based on helical structures containing 7-membered fused rings

Three novel isomeric helical molecules 2-methoxy-m,n-dimethyl-6-phenyl-6H-5,6,7-triazadibenzo[f,h]naphtho[3,2,1-cd]azulenes (m,n = 8,9; 8,10; 9,10), derived from alkylated 1H-pyrazolo[3,4-b]quinoline halides, were synthesized. Their twisted structures containing a seven-membered ring help to sustain a glassy state, which enables a film of good quality to be formed. All compounds exhibit distinct glass transition temperatures (98, 100 and 113 °C, respectively). The racemization barrier of the dyes is rather low, ∼25 kcal/mol. In consequence the compounds were obtained as racemic mixtures, both in solution and crystalline state. The helical structure of azulenes can be clearly seen from their crystal structures; however the racemates belong to centrosymmetric space groups. Finally, the helical dyes were successfully applied as a direct light emitting layer in OLED cell. The configuration of the devices: ITO/PEDOT:PSS/azulene/Ca/Al, emitting greenish-yellow light with CIE coordinates (0.44, 0.54) is reported

Linear and ring polymers in confined geometries

A short overview of the theoretical and experimental works on the polymer-colloid mixtures is given. The behaviour of a dilute solution of linear and ring polymers in confined geometries like slit of two parallel walls or in the solution of mesoscopic colloidal particles of big size with different adsorbing or repelling properties in respect to polymers is discussed. Besides, we consider the massive field theory approach in fixed space dimensions d = 3 for the investigation of the interaction between long flexible polymers and mesoscopic colloidal particles of big size and for the calculation of the correspondent depletion interaction potentials and the depletion forces between confining walls. The presented results indicate the interesting and nontrivial behavior of linear and ring polymers in confined geometries and give possibility better to understand the complexity of physical effects arising from confinement and chain topology which plays a significant role in the shaping of individual chromosomes and in the process of their segregation, especially in the case of elongated bacterial cells. The possibility of using linear and ring polymers for production of new types of nano- and micro-electromechanical devices is analyzed