Self-healing and mechanical performance of dynamic glycol chitosan hydrogel nanocomposites

Abstract

Evaluation of Schiff base nanocomposite hydrogels properties using a benzaldehyde multifunctional amphiphilic polyacrylamide crosslinker in conjunction with glycol chitosan.

Challenges and Opportunities of Self‐Healing Polymers and Devices for Extreme and Hostile Environments

“…However, to date there have been limited reports where these techniques have been used in the development of polymers that can function and self‐heal in extreme environments. Future work in this area should focus on using the synthetic control offered by RDRP techniques, such as reversible addition‐fragmentation chain‐transfer polymerization and atom transfer radical polymerization, to design polymers that have the functionality for dynamic bonding evenly distributed through each polymer chain, or that are confined in single blocks, [ 136 ] or the terminal groups of large dendritic structures. These techniques offer the potential to build on and optimize the results achieved through the functionalization of commercial materials to enable mass manufacture and low‐cost processing of self‐healing polymers.…”

Dynamic protein and polypeptide hydrogels based on Schiff base co-assembly for biomedicine

“…Besides enzyme-mediated functionalisation, chemical routes to functional group modification also help improve the crosslinking density, stimuli-responsiveness, and biocompatibility of dynamic protein and polypeptide hydrogels. 62 Hydrogelators can be chemically modified by either (1) converting their amino, carboxyl, or hydroxyl groups into amides or esters by coupling with hydrazides 63 or carbodiimides, 64 (2) regioselectively oxidizing glycols by periodic acid or periodates, 65 or (3) using small molecular weight dialdehyde or mono-aldehyde crosslinkers to assist Schiff base formation. 38 Hydrazide/carbodiimide coupling and regioselective oxidation of glycols are the most common one-pot routes to functional modification, as aldehyde crosslinkers are cytotoxic and may dissociate from the hydrogels under physiological conditions.…”

Well-defined polyacrylamides with AIE properties via rapid Cu-mediated living radical polymerization in aqueous solution: thermoresponsive nanoparticles for bioimaging

“…The Haddleton group introduced a novel synthetic route to perform aqueous copper-mediated RDRP via the in situ formation of Cu containing catalysts exploiting the rapid disproportionation (<10 seconds) as an advantageous driving force. [32][33][34] ATRP in water has often been described as being problematic with a Cu/tris(2-pyridylmethyl)amine (TPMA) complex being described as being the best and most versatile catalyst to employ in water 35 even though the quite popular Me 6 Tren has been shown to be efficient. [32][33][34] This rapid rate of polymerization requires a high radical concentration at any moment in time, however, the excellent control we were seeking is often thought to require a low concentration of radicals, which is somewhat contradictory.…”

“…[32][33][34] ATRP in water has often been described as being problematic with a Cu/tris(2-pyridylmethyl)amine (TPMA) complex being described as being the best and most versatile catalyst to employ in water 35 even though the quite popular Me 6 Tren has been shown to be efficient. [32][33][34] This rapid rate of polymerization requires a high radical concentration at any moment in time, however, the excellent control we were seeking is often thought to require a low concentration of radicals, which is somewhat contradictory. Ballard and Asua have described how this apparent contradiction can be explained by taking into account radical diffusion time which explains this rapid and efficient polymerization.…”