[en] The technique of activators generated by electron transfer for atom transfer radical polymerization (AGET-ATRP) of acrylonitrile (AN) has been first attempted in emulsion using the procedure of “one-pot”, “two-step” with polyethylene glycol monooleyl ether (Brij 35) as surfactant, cupric chloride (CuCl₂) as catalyst, hexamethylenetetramine (HMTA) as ligand, carbon tetrachloride (CCl₄) as initiator and ascorbic acid (VC) as reducing agent. The polymerization proceeds in controlled/living manner as indicated by first-order kinetics of the polymerization rate with respect to the monomer concentration, linear increase of the molecular weight of polyacrylonitrile (PAN) with monomer conversion and narrow polydispersity. Monomer conversion increases initially with the increase of ligand HMTA and then decreases. The ratio of [AN1] to [AN2] at 1:3 not only gives better control on the molecular weight and the molecular weight distribution, but also provides a more rapid polymerization rate. The rate of polymerization shows a trend of increase along with CCl₄ content. The apparent activation energy of the polymerization is calculated to be 46.6 kJ/mol. Chain extension of PAN with AN was also carried out and the chain extended PAN with 20520 molecular weight and 1.36 polydispersity was successfully obtained. - Graphical abstract: Kinetic plot for AGET ATRP of AN in emulsion AGET-ATRP of AN has first investigated in emulsion with HMTA as ligand, CCl₄ as initiator and VC as reducing agent. The polymerizations have been successfully conducted in a controlled manner in the presence of air as evidenced by a linear first-order kinetic plot and linear increase of molecular weight with monomer conversion. Highlights: ► AGET-ATRP of AN is first investigated in emulsion. ► HMTA is used as ligand. ► Chain extension of PAN with AN verifies the living nature of the polymerization system.

[en] Graphical abstract: Chiral ionic liquids, [C₂mim][LLA], [C₄mim][LLA] and [C₆mim][LLA] were firstly applied as both ligand and reaction media for atom transfer radical polymerization using activators generated by electron transfer (AGET ATRP) of acrylonitrile (AN) with ascorbic acid (VC) as reducing agent in the presence of air. A small but clear increase of polyacrylonitrile (PAN) isotacticity was observed for AGET ATRP ofANin [C6mim][LLA] than in [C6mim][BF4]. PAN isotacticity markedly increased with the content of [C₆mim][LLA]. Compared with in [C₂mim][LLA] and [C₄mim][LLA], the rate of AGET ATRP of AN in [C₆mim][LLA] was fastest and the polymerization was best controlled. Well-defined PAN with molecular weight at 76,590, relatively narrower distribution at 1.27 and higher isotacticity at 0.37 was successfully prepared in [C₆mim][LLA]. Highlights: → Chiral ionic liquids, [C₂mim][LLA], [C₄mim][LLA] and [C₆mim][LLA] were firstly applied as both ligand and reaction media for AGET ATRP of AN in the presence of air. → A small but clear increase of polymer isotacticity was observed for AGET ATRP of AN in [C₆mim][LLA] than in [C₆mim][BF₄]. → Well-defined PAN with molecular weight at 76,590, relatively narrower distribution at 1.27 and higher isotacticity at 0.37 was successfully prepared in [C₆mim][LLA]. - Abstract: Chiral ionic liquids, [C₂mim][LLA], [C₄mim][LLA] and [C₆mim][LLA] were firstly applied as both ligand and reaction media for atom transfer radical polymerization using activators generated by electron transfer (AGET ATRP) of acrylonitrile (AN) with ascorbic acid (VC) as reducing agent in the presence of air. A small but clear increase of polyacrylonitrile (PAN) isotacticity was observed for AGET ATRP of AN in [C₆mim][LLA] than in [C₆mim][BF₄]. PAN isotacticity markedly increased with the content of [C₆mim][LLA]. Compared with in [C₂mim][LLA] and [C₄mim][LLA], the rate of AGET ATRP of AN in [C₆mim][LLA] was fastest and the polymerization was best controlled. Well-defined PAN with molecular weight at 76,590, relatively narrower distribution at 1.27 and higher isotacticity at 0.37 was successfully prepared in [C₆mim][LLA].

[en] Atom transfer radical polymerization using activators generated by electron transfer (AGET ATRP) of acrylonitrile (AN) was carried out for the first time in 1-methylimidazolium acetate ([mim][AT]), 1-methylimidazolium propionate([mim][PT]), and 1-methylimidazolium butyrate ([mim][BT]), respectively. The polymerization was approached by using ascorbic acid (VC) as a reducing agent, ethyl 2-bromoisobutyrate (EBiB) as initiator, only FeBr₃ as catalyst without any additional ligand. Kinetic studies showed that both AGET ATRP of AN in the absence of oxygen and in the presence of air proceeded in a well-controlled manner. Under the same conditions, the polymerization in the presence of air provided rather slower reaction rate and showed better control of molecular weight and its distribution than in the absence of oxygen. The sequence of the apparent polymerization rate constants of AGET ATRP of AN in three ionic liquids was k_app([mim][AT]) > k_app([mim][PT]) > k_app([mim][BT]). The living nature of the polymerization was confirmed by chain end analysis and block copolymerization of methyl methacrylate with polyacrylonitrile as macroinitiator. All the three ionic liquids and FeBr₃ could be recycled and reused and had no effect on the living nature of polymerization.