Controlled/“living” radical polymerization of styrene catalyzed by FeCl2/succinic acid

Abstract

A new ligand, succinic acid, was successfully used for atom transfer radical polymerization. The reaction was carried out at 40 to 100°C in bulk with α‐bromoethyl benzene as the initiator and FeCl2/(succinic acid) as the catalyst system. The molecular weight of the resulting polymer increases with increasing monomer conversion, however, it is somewhat lower than the theoretical value. The polydispersity index is relatively low (Mw/Mn = 1.30) even though there may be a possible chain transfer reaction during the polymerization. The enthalpy of the equilibrium between active species and dormant ones was calculated to be 2.15 kcal/mol.

Electron transfer reactions relevant to atom transfer radical polymerization

“…Much research has focused on developing novel nitrogen-based ligands for Cu complexes in an effort to adjust the redox potential of the catalysts, and in turn, affect the position of the ATRP equilibrium (vide infra) [14][15][16][17]. Additionally, the range of transition metals employed in ATRP continues to be expanded in the search for more powerful catalysts and now includes Ti, [18] Mo, [19][20][21][22] Re, [23][24][25] Ru, [2,[26][27][28][29][30][31][32] Fe, [33][34][35][36][37][38][39][40][41] Rh [26,[42][43][44][45], Ni, [43,[46][47][48][49][50][51][52][53] Pd, [54] Co, [55] Os, [56] and Cu [1,6,…”

Reverse ATRP of acrylonitrile with diethyl 2,3-dicyano-2,3-diphenyl succinate/FeCl3/iminodiacetic acid

“…However, acids, which are inexpensive and nontoxic, complex more easily with iron and may, therefore, act as a ligand. Shenmin has reported ATRP of styrene catalyzed by FeCl 2 / succinic acid [36]. Given these concepts, this study was firstly to investigate the synthesis of polyacrylonitrile with high molecular weight and narrow polydispersity using RATRP of AN.…”

Iron-catalyzed atom transfer radical polymerization

“…Yan et al [334][335][336][337][338] which provided a homogeneous catalyst system (M w /M n < 1.5). 336 FeCl 3 /acetic acid could be employed as catalyst for reverse ATRP of AN in the presence of AIBN initiator.…”