Vitreoretinal tamponades based on fluorosilicone fluids

[0027] Embodiment 1-ring-opening / hydrosilation process:

[0028] Trimethylsilyl-terminated poly(25mol% methylsiloxane)-co-(75mol% dimethylsiloxane) (T 2 D. 75 D. 25 H) Synthesis

[0029] Under nitrogen atmosphere, add octamethylcyclotetrasiloxane (D 4 (371.9g, 1.25mol)), tetramethylcyclotetrasiloxane (D 4 H (100.4g, 0.42mol)) and hexamethyldisiloxane (T 2 (0.7 mol)). Trifluoromethanesulfonic acid (0.25%, 1.25 g, 8.3 mmol) was added as an initiator. The reaction mixture was stirred vigorously at room temperature for 24 hours. Sodium bicarbonate (10 g, 0.119 mol) was then added and the reaction mixture was stirred again for 24 hours. The resulting solution was filtered through a 0.3 [mu]Teflon(R) (E.I. DuPont de Nemours and Company, Wilmington, Delaware) filter. The filtrate was vacuum stripped and placed under vacuum (>0.1 mmHg) at 50°C to remove unreacted siloxane rings. The resulting silane-functionalized siloxane was a viscous, clear liquid (70% yield; SEC: Mn = 75...

[0030] The general process of embodiment 2-fluorine side chain siloxane synthesis

[0031] Poly(25 mol% (3-(2,2,3,3,4,4,5,5-octafluoropentyloxy)propylmethylsiloxane)-co-(75 mol% dimethylsilyl oxane) synthesis

[0032] Under a nitrogen blanket, add T to a 500 mL round bottom flask equipped with a magnetic stirrer and water condenser 2 D. 75 D. 25 H (0.002 mol), allyloxyoctafluoropentane (27.2 g, 0.1 mol), tetramethyldisiloxane platinum complex (2.5 mL of a 10% solution in xylene), 75 mL of dioxygen Hexacyclic and 150 mL of anhydrous tetrahydrofuran. The reaction mixture was heated to 75 °C and the IR and 1 H-NMR measures the loss of silane to monitor the reaction. The reaction was complete after 4 to 5 hours at reflux. The resulting solution was placed on a rotary evaporator to remove THF and dioxane. The obtained crude product was diluted with 300 mL of 20% dichloromethane in pentane, and passed through a 15 g silica gel column with dichloromethane in pentane as the el...