THF GPC

Polyether 618 The sulfonium polyelectrolyte 617 was dissolved in a minimal amount of methanol. The solution was stirred for 1 week under argon, during which pendant polyether 618 precipitated from the solution. The tacky yellow material was completely soluble in CHC13 and THF. Polymer 618 can be dissolved in THF and passed through a 0.2-mm filter for GPC or for use in film casting and device fabrication. Cast films can be completely redissolved into CHC13 or THF. GPC in THF (polystryrene standards) gave A/w = 91,500 and Mn = 33,800. 

Molecular weight distributions were assessed using THF GPC or aqueous GPC, respectively. 

Polymers were prepared using catalyst 4 (see Figure 3). Theoretical molecular weights calculated based on catalyst to monomer ratio, assuming full conversion. Determined by THF GPC relative to polystyrene standards prior to deprotection of polymer. Determined by water GPC relative to poly(ethylene oxide) standards. Determined by DMF GPC relative to polystyrene standards prior to the hydrolysis of polymer. 

FIGURE 6.1 Calibration curves of Shodex GPC KF-BOO series. Column Shodex GPC KF-800 series 8 mm i.d. X 300 mm. Eluent THF. Sample Polystyrene standards. 

It is well known that pMMA and pSty in THF follow ideal GPC behavior on many common GPC columns. However, many commercially important acrylate polymers contain a wide array of other monomers. In general, acrylic polymers composed of monomers that do not contain polar groups will yield well-behaved polymers, giving ideal GPC separations. Monomers that contain polar groups should prompt the analyst to carefully evaluate the possibility of adsorption of the analyte onto the column. The most common functionalities of concern are hydroxyl groups, amine groups, ethylene oxide units, and carboxylic acids. In many cases, such monomers can be tolerated. However, the acceptable level can vary considerably with even apparently minor changes in... 

Under nitrogen, a mixture of 97 (2 eq.), 2,6-dibromo-l-dedocyloxy-4-methylbenzene 98 (1 eq.), and Pd(PPli3)2Cl2 in THF was stirred at reflux for 24 h. Polymer 99 was purified by repetitive precipitation-centrifugation using THF and MeOH. GPC (polystyrene standards) Mn = 1700, PDI = 1.4. 

To a mixture of 1,3-dibromobenzene (4.36 g, 18.49 mmol), 1,3-phenylene diamine 111 (2.00 g, 18.49 mmol), NaO-t-Bu (3.73 g, 38.84 mmol), Pd2(dba)3 (0.339 g, 0.37 mmol), and BINAP (0.691 g, 1.11 mmol) in a heavy-walled flask equipped with a Teflon valve was added THF (15 mL) under inert atmosphere. The flask was sealed and heated to 90°C. After 24 h, die reaction mixture was cooled to room temperature and neutralized using 0.2 mol equivalents of 2.4 N HC1 in MeOH. The polymer was precipitated from hexanes, filtered, and dried under vacuum. The dried polymer was redissolved in THF, filtered through Celite, and reprecipitated. The solid was collected by filtration and dien purified by Soxlilet extraction with CH2C12 overnight. After drying under vacuum, a green-tan solid was obtain in 106% yield. GPC (NMP, polystyrene standards) Mw = 39,000 ... 

Under nitrogen, 115( 1 eq.) was reacted with BuLi (2 eq.) at 0°C for 1 h followed by treatment with trimethyltin chloride (2.5 eq.) in THF at room temperature for 30 min. Then a solution of 116 (1 eq.) and PdCl2(Ph3As)2 (0.02 eq.) in THF was combined and the mixture was stirred at reflux overnight. The polymer was precipitated with MeOH followed by filtration and dried under vacuum. GPC (polystyrene standards) Mn = 2000. 

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