Ring-opening polymerization (ROP) of monofunctional neopentylglycol carbonate (NPGC) with or without bifunctional di(trimethylolpropane) carbonate (DTMPC), which are derived from available corresponding alcohols, affords linear polycarbonates or covalently-linked polycarbonate networks, respectively. A series of available ethanol amine derivatives having the different numbers of 2-hydroxylethyl arms (N, N, N', N'-tetrakis(2-hydroxyethyl) ethylenediamine, triethanolamine, N-methyldiethanolamine or N, N-dimethylethanolamine) initiates the ROP of NPGC to afford star-shaped, telechelic, or linear polycarbonates bearing tertiary amines with well-controlled molecular weights and relatively narrow polydispersities Furthermore, the copolymerization of NPGC and DTMPC in the presence of these initiators readily gives tertiary amine-modified polycarbonate films with well transparency and flexibility. These amino groups are easily converted to ammonium salts by protonation with acids, while the quaternization with benzyl bromide is strongly affected by the steric hindrance of these amines. N-Methyldiethanolamine or N, N-dimethylethanolamine residues in these films react easily with benzyl bromide to give quaternary ammonium salt-functionalized films. (C) 2015 Wiley Periodicals, Inc.