Synthesis of block copolymer containing dextran and polyamide sequences

Abstract

A novel AB‐type block copolymer composed of dextran and polyamide sequences was prepared through the following two approaches. One is a coupling reaction of a terminal functional group introduced in the dextran chain with that in the polyamide chain, such as the reaction of an amine group with an acyllactam group or that of a lactone group with an amine group at the corresponding chain ends. The other is an anionic polymerization of a bicyclic lactam activated with a trimethylsilylated dextran derivative having an acyllactam end group. The latter procedure was found to be more effective for the preparation of the block copolymer having a high molecular weight polyamide sequence.

Proton transfer-controlled anionic polymerization of methyl-substituted ?-lactams with potassiumt-butoxide and subsequent coupling reaction with saccharides

“…Similar behavior of t-butanol had already been reported in the anionic polymerization of a bicyclic lactam, 8-oxa-6-azabicyclo[3.2.1]octan-7-one, in dimethyl sulfoxide. 21 From that work and the present results, potassium t-butoxide, which is commercially available, is more convenient than potassium pyrrolidonate as a catalyst in the living polymerization of lactams.…”

Polysaccharide‐Containing Block Copolymers: Synthesis, Properties and Applications of an Emerging Family of Glycoconjugates

“…Ring opening polymerizations of polypeptide, polyether, polyamide and polyester from polysaccharides with suitably modified end groups (adapted from ref. [49,50,52,53] ).…”

“…Following an investigation of the various routes to convert the reducing end of a dextran to lactone, amine and acyllactam group, [36] Hashimoto et al [52] reported on the synthesis of diblock copolymers of dextran and hydrophilic polyamide. The copolymers were obtained by anionic ROP of a bicyclic oxalactam from a trimethylsilylated dextran…”

Thermoresponsive Self-Assemblies of Cyclic and Branched Oligosaccharide-block-poly(N-isopropylacrylamide) Diblock Copolymers into Nanoparticles

“…36 Thus, the thermoresponsive self-assembly behavior of βCyD-b-PNIPAM and XGOb-PNIPAM were characterized by static (elastic) and dynamic (quasi-elastic) light scattering analysis. Elastic light scattering intensities of aqueous solutions of the diblock copolymers (0.2 g L −1 ) were measured in a range of temperatures from 25 °C (Figure 4). First, the samples were heated up step-by-step from 25 to 60 °C and then cooled down step-by-step to 25 °C at a heating/cooling rate of roughly 1 °C min −1 .…”

“…As the synthetic blocks of the saccharide-based hybrid block copolymers, commonly used polymers (e.g., polystyrene, − polyacrylates, − poly(vinyl acetate), and polyamides) and biocompatible polymers (e.g., polypeptides, − poly(ε-caprolactone), , and poly(ethylene glycol) − ) have been adopted so far. Although some of these hybrid block copolymers self-assemble into nanoparticles in selective solvents, these nanoparticles hardly vary their structures in response to external stimuli.…”