Chain transfer to solvent in the radical polymerization of structurally diverse acrylamide monomers using straight-chain and branched alcohols as solvents

Dispersion polymerization of acrylamide with living character and controlled morphologies initiated and mediated by cobalt porphyrin

“…[8][9] The sulfonated cobalt porphyrin complexes (TMPS)Co(II) were used to mediate the LRP of acrylic acid in water. Fortunately, the LRP of acrylamide could be obtained via reversible addition fragmentation transfer (RAFT), [20][21][22][23] nitroxide mediated radical polymerization (NMP) [24][25][26] and atom transfer radical polymerization (ATRP), [27][28][29][30] and so on. [10] Cobalt porphyrin substituted by three mesityl groups and one phenyl group with a long chain alcohol at the para position was designed to increase the solubility in different solvents.…”

Synthesis of fluorinated alkoxyamines and alkoxyamine-initiated nitroxide-mediated precipitation polymerizations of styrene in supercritical carbon dioxide

“…To a solution of TIPNO-OH alkoxyamine 46 (0.6962 g, 1.961 mmol) and 4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,11-heptadecafluoroundecanoyl chloride (1.001 g, 1.961 mmol) in 30 mL of anhydrous dichloromethane was added triethylamine (0.1997 g, 1.961 mmol) at room temperature. The reaction mixture was stirred for 1 hour, then 50 mL of dichloromethane and 50 mL of H 2 O were added.…”

“…[1][2][3] Advantages include a readily accessible critical point (31 °C and 7.4 MPa), 4 variable solubility by subtle changes in pressure and temperature, 5 and the lack of chain transfer to solvent in radical polymerizations. 6,7 It is particularly well-suited for heterogeneous radical polymerizations, since reagents such as the monomer, initiator and controlling agent are generally soluble in scCO 2 , but the resultant polymer is insoluble and precipitates. 2,3 If the precipitation system is carried out in the presence of a colloidal stabilizer to prevent coagulation of particles, then dispersion polymerization results giving polymer of narrow particle size distributions and well-defined particles (d ≈ 100 nm to 15 μm).…”

“…6,7 It is particularly well-suited for heterogeneous radical polymerizations, since reagents such as the monomer, initiator and controlling agent are generally soluble in scCO 2 , but the resultant polymer is insoluble and precipitates. 2,3 If the precipitation system is carried out in the presence of a colloidal stabilizer to prevent coagulation of particles, then dispersion polymerization results giving polymer of narrow particle size a The monomer is not always soluble in the reaction medium, such as in the controlled/living nitroxide-mediated radical polymerization (NMP) of N-isopropylacrylamide (NIPAM) in scCO 2 , where an inverse suspension system is generated.…”

“…The performance of these fluorinated alkoxyamines in polymerizations of styrene in scCO 2 is compared with analogous polymerizations in solution, as well as, TIPNO and SG1-alkoxyamine 1a and 1d analogues. 4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,, triethyl amine (Aldrich), ethylenediamine (Aldrich), Mn(OAc) 2 •4H 2 O (Acros Organics), pyridine (Acros Organics), (3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,12-henicosafluorododecyl), diisopropyl-silane (Fluorous Technologies Inc.), trifluoromethanesulfonic acid (TCI America), 1H, 1H, 2H, 2H-perfluorodecanol (Matrix Scientific), tetrabutylammoniumhydrogen sulfate (TCI America), 2-hydroxybenzaldehyde (EMD), and sodium hydroxide (Fisher Scientific) were used as received. Dichloromethane (Fisher Scientific) was dried over calcium hydride (Fisher Scientific) when anhydrous conditions were required.…”