Grafting onto preformed polyester network using thermolabile azo groups

Abstract

SynopsisPolycondensation of 4,4-azo-bis(cyanopentanoyl chloride) and o-phthalyl chloride between polyethylene glycol with addition of glycerine leads to polyester networks containing thermolabile azo groups. The networks have been characterized in terms of their swelling in benzene, chlorobenzene, and methacrylonitrile. Grafting of methacrylonitrile onto these preformed networks was then achieved by thermal decomposition of -N=N-groups in the presence of methacrylonitrile.

Polyacrylamide Containing Weak Temperature Labile Azo Links in the Polymer Backbone

“…Azo linkages have drawn a lot of attention due to their thermal, chemical, photochemical, and biological properties. − Aromatic azo groups confer biodegradability, which enables to use them as a delivery vehicle in targeted drug delivery. − Aliphatic azo groups are thermally cleavable, creating free radicals which are used for the synthesis of block or graft copolymers . The incorporation of azo compounds into a polymer backbone opens the way to thermo- and photodegradable polymers. − …”

“…13 The incorporation of azo compounds into a polymer backbone opens the way to thermo-and photodegradable polymers. [14][15][16] Azo-containing polymers can be prepared by condensation, radical, cationic, and anionic polymerization. 17,18 An alternative strategy is based on using bifunctional initiators compromising azo groups to polymerize vinyl monomers.…”