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An approach to activating Pd-complexes without using additives such as Lewis acids has been developed for addition polymerization of norbornenes. Aryl iodides and aryl diazonium salts were efficiently applied as cocatalysts to Pd(0)- and Pd(2+)-complexes. The developed systems catalyzed polymerization of norbornenes containing bulky and polar functional groups both in an inert atmosphere and air resulting in soluble and high-molecular-weight saturated polymers.

Polynorbornenes represent a fruitful class of polymers for structure-property study. Recently, vinyl-addition polynorbornenes bearing side groups of different natures were observed to exhibit excellent gas permeation ability, along with attractive C 4 H 10 /CH 4 and CO 2 /N 2 separation selectivities. However, to date, the gas transport properties of fluorinated addition polynorbornenes have not been reported. Herein, we synthesized addition polynorbornene with fluoroorganic substituents and executed a study on the gas transport properties of the polymer for the first time. A norbornene-type monomer with a C 6 F 5 group, 3-pentafluorophenyl- exo -tricyclononene-7, was successfully involved in addition polymerization, resulting in soluble, high-molecular-weight products obtained in good or high yields. By varying the monomer concentration and monomer/catalyst ratio, it was possible to reach M w values of (2.93-4.35) × 10 5 . The molecular structure was confirmed by NMR and FTIR analysis. The contact angle with distilled water revealed the hydrophobic nature of the synthesized polymer as expected due to the presence of fluoroorganic side groups. A study of the permeability of various gases (He, H 2 , O 2 , N 2 , CO 2 , and CH 4 ) through the prepared polymer disclosed a synergetic effect, which was achieved by the presence of both bulky perfluorinated side groups and rigid saturated main chains. Addition poly(3-pentafluorophenyl- exo -tricyclononene-7) was more permeable than its metathesis analogue by a factor of 7-21, or the similar polymer with flexible main chains, poly(pentafluorostyrene), in relation to the gases tested. Therefore, this investigation opens the door to fluorinated addition polynorbornenes as new potential polymeric materials for membrane gas separation.

Purpose: To compare the changes of the macular morphological and functional parameters in the postoperative period in patients with silicone oil tamponade after successful surgery of the macula-on rhegmatogenous retinal detachment (RRD)., Material and Methods: The study included 20 eyes operated on for macula-on RRD, which made up the first group, and the control group (20 eyes) for comparison. All patients of the study group underwent vitrectomy using silicone oil tamponade. Standard ophthalmological examination was performed on the 3rd day (early postoperative period) and the 14th day (late postoperative period), including OCT and OCT-A that were used to assess morphological and functional changes., Results: A significant decrease in visual acuity was seen on the 3rd day after surgery involving the use of silicone oil tamponade, in comparison with the 14th day ( p =0.0237) and the control group ( p =0.0001). A decrease in the FD parameter ( p =0.045), a decrease in vascular density in the fovea ( p =0.020) and parafovea ( p =0.024) in SCP were found on the 3rd day in comparison with control. On the 14th day of postoperative observation, a tendency was detected for choroidal perfusion to restore, as well as significant increase in FD ( p =0.016), and an increase in vascular density in parafovea ( p =0.01) compared with the early postoperative period. No statistically significant changes were seen in the FAZ area and vessel density DCP ( p >0.05).