TY  - JOUR
A1  - Vacogne, Charlotte D.
A1  - Schlaad, Helmut
T1  - Controlled ring-opening polymerization of alpha-amino acid N-carboxyanhydrides in the presence of tertiary amines
JF  - Polymer : the international journal for the science and technology of polymers
N2  - The mechanism of the primary ammonium/tertiary amine-mediated ring-opening polymerization of gamma-benzyl-L-glutamate N-carboxyanhydride (BLG-NCA) was investigated. Kinetic analyses revealed that the normal amine mechanism (NAM) together with a dormant-active chain end equilibrium were responsible for the controlled nature of this polymerization pathway, but that the polymerization also proceeded via the activated monomer mechanism (AMM). Mixtures of primary amines (1 equiv) and tertiary amines (0-1.5 equiv) were therefore tested to confirm the co-existence of the NAM and AMM and determine the limits for a controlled polymerization. For tertiary amine molar fractions smaller than 0.8 equiv, the reaction times were greatly reduced (compared to primary amine-initiated polymerization) without compromising the control of the reaction. Hence, the polymerization of NCA can proceed in a controlled manner even when the AMM contributes to the overall chain growth mechanism. (C) 2017 Elsevier Ltd. All rights reserved.
KW  - Ring-opening polymerization
KW  - Amino acid N-carboxyanhydride
KW  - NCA
KW  - Kinetics
KW  - Mechanism
Y1  - 2017
U6  - https://doi.org/10.1016/j.polymer.2017.07.062
SN  - 0032-3861
SN  - 1873-2291
VL  - 124
SP  - 203
EP  - 209
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Secker, Christian
A1  - Robinson, Joshua W.
A1  - Schlaad, Helmut
T1  - Alkyne-X modification of polypeptoids
JF  - European polymer journal
N2  - Poly(N-propargyl glycine) (PNPG) can be readily prepared by ring-opening polymerization of N-propargyl glycine N-carboxyanhydride (NCA) and modified using various addition reactions such as copper catalyzed [3+2] cycloaddition of azide, radical (photo-)addition of thiol, nucleophilic addition of ethylene oxide, and thermal induced cross-linking. It is demonstrated that PNPG can serve as a modular platform to produce a bibliography of novel functional polypeptoid or pseudopeptide materials, including polypeptoid ionic liquids and graft copolymers.
KW  - Polypeptoid
KW  - NCA
KW  - Post-polymerization modification
KW  - Click chemistry
Y1  - 2015
U6  - https://doi.org/10.1016/j.eurpolymj.2014.08.028
SN  - 0014-3057
SN  - 1873-1945
VL  - 62
SP  - 394
EP  - 399
PB  - Elsevier
CY  - Oxford
ER  -