Synthesis and purification of a poly(ethylene oxide)-poly(γ-benzyl-l-glutamate) diblock copolymer bearing tyrosine units at the block junction

Preparation of Well‐Defined Diblock Copolymers with Short Polypeptide Segments by Polymerization of N‐Carboxy Anhydrides

“…Nevertheless, 1 H NMR spectra of the purified polymer clearly indicate that both polymers PEO and P(BLG) coexist in the analyzed sample. Since after treatment in cold DMF, no homopolymer of g-benzyl-Lglutamate can subsist in the sample, [16] the 1 H NMR data proves that the molecular structure of the sample consists only of covalently conjugated PEO and P(BLG) segments (i.e., a well-defined diblock structure). Recently, Fukuda reported a convenient formula for calculating the polydispersity index of a second block in a diblock copolymer.…”

“…In that case, the homopolymer was separated from the diblock copolymer by selective precipitation of the diblock in cold DMF (À20 8C). [16] …”

Double-Hydrophilic Block Copolymers: Synthesis and Application as Novel Surfactants and Crystal Growth Modifiers

“…Hydrophilic, salt responsive block GTP [54] Poly(N-isopropylacrylamide), (PNIPAAm) [46,71,[73][74][75][76][77][78][79][80][81][82][83][84][85][86][87][88][89][90] patent by BASF where living PMMA anions were used to initiate the polymerization of ethylene oxide (EO). [21] The same strategy was reported in the literature.…”

“…Syntheses were described for the ABA triblock with PEO as the B block, [82 -85] which could be modified for the AB block if a-methyl-xamino[poly(ethylene oxide)] or a-(2-N,N-ethylamino)-xmethoxy[poly(ethylene oxide)] were used as initiators. [86] However, the commercially available PEO-NH 2 contains considerable amounts of impurities and, especially, the bifunctional chains have to be excluded in order to avoid the formation of triblocks requiring repeated precipitation of the initiator from a CH 2 Cl 2 /EtOH (1 : 1) solution with diethyl ether. Removal of PGlu homopolymer after polymerization could be carried out by precipitation of the block copolymer with cold DMF, re-dissolution in CHCl 3 and repeated precipitation with diethyl ether leading to the pure block copolymer with M -w /M -n = 1.26.…”

Correlation between structures of chiral polymers and their efficiency for chiral resolution by crystallization

“…[22][23][24] The most frequently used route toward copolymers with polypeptide block segments is by the ring-opening polymerization of protected amino acid-N-carboxyanhydrides (NCA), initiated by an amino functional polymer.…”