4823-47-6Relevant articles and documents
RAFT polymerization and thio-bromo substitution: An efficient way towards well-defined glycopolymers
Pr?hl, Michael,Englert, Christoph,Gottschaldt, Michael,Brendel, Johannes C.,Schubert, Ulrich S.
, p. 3617 - 3626 (2017)
Despite an increasing effort to design well-defined glycopolymers, the convenient synthesis of polymers with higher DPs (>100) and without tedious protection and deprotection steps remains a challenge. Combining the reversible addition fragmentation transfer (RAFT) polymerization and the efficient substitution of primary bromo groups by thiols, we were able to synthesize a set of well-defined glycopolymers with DPs of up to 115. With the polymerization of the highly reactive monomer (2-bromoethyl)-acrylate polymers with low dispersities were obtained that could efficiently be functionalized with various sugar thiol(ate)s. In particular, derivatives of d-glucose, d-galactose, and d-mannose gave excellent degrees of functionalization close to quantitative conversion using only a slight excess of the thiol. This atom efficient synthesis can even be applied for copolymers with acid or base labile components due to the use of unprotected sugar moieties and, hence, the lack of further deprotection steps. Binding studies with the lectin concanavalin A and the subsequent competition studies with α-d-methyl-mannopyranose (αMeMan) proved the effective binding of these derivatives and revealed a DP- and carbohydrate-dependent clustering and dissolution.
Poly(bromoethyl acrylate): A Reactive Precursor for the Synthesis of Functional RAFT Materials
Barlow, Tammie R.,Brendel, Johannes C.,Perrier, Sébastien
, p. 6203 - 6212 (2016)
Postpolymerization modification has become a powerful tool to create a diversity of functional materials. However, simple nucleophilic substitution reactions on halogenated monomers remains relatively unexplored. Here we report the synthesis of poly(bromoethyl acrylate) (pBEA) by reversible addition-fragmentation chain transfer (RAFT) polymerization to generate a highly reactive polymer precursor for postpolymerization nucleophilic substitution. RAFT polymerization of BEA generated well-defined homopolymers and block copolymers over a range of molecular weights. The alkylbromine-containing homopolymer and block copolymer precursors were readily substituted by a range of nucleophiles in good to excellent conversion under mild and efficient reaction conditions without the need of additional catalysts. The broad range of nucleophilic species that are compatible with this postmodification strategy enables facile synthesis of complex functionalities, from permanently charged polyanions to hydrophobic polythioethers to glycopolymers.
Solid-state, individual dispersion of single-walled carbon nanotubes in ionic liquid-derived polymers and its impact on thermoelectric properties
Nakano, Motohiro,Nonoguchi, Yoshiyuki,Nakashima, Takuya,Hata, Kenji,Kawai, Tsuyoshi
, p. 2489 - 2495 (2016/01/20)
The structure of carbon nanotubes and their electronic interaction with a matrix are important for extracting the unprecedented electronic properties, which have yet to be explored. Here we investigate the dispersibility of single-walled carbon nanotubes (SWNTs) in ionic liquid-derived polymers (PILs), revealed by cross-sectional transmission electron microscopy, infrared optical spectroscopy, and Raman spectroscopy. Surprisingly, SWNTs studied here are highly dispersed, at least down to 7.5 nm-fibres, in a trimethylammonium-suspended PILs. Based on this discovery, we found that the well-dispersed and almost fully dispersed SWNTs in PILs are responsible for the enhanced thermoelectric properties, a future energy harvesting technique.
