The synthesis of the azo molecule 1‐(2‐(4‐nitrophenyl) diazenyl) naphtalen‐2‐ol which has been functionalized with a methacryloxyl fraction is now reported. This azo monomer was copolymerized with methyl methacrylate (MMA) by ATRP where the active species is prepared “in situ” after the reduction reaction of the metal complex Cu (II) ‐ HMTETA by tin 2‐ethylhexanoate in 2‐butanone as solvent. Experimental conditions for the controlled homopolymerization of MMA were established. By adjusting the amount of reducing agent, a good correlation between theoretical and experimental molecular weight was obtained. Such conditions were also employed for the random copolymerization of MMA with the synthesized azo monomer.

Summary: Photoactive monomers [(E)-1(4-methacryloxyphenyl)-2-(nitrophenyl) diazene] (azo 1) and (E)-1-(4-methacryloxyethyl-phenyl)-2-phenyl-diazene (azo2) were synthesized. The azo 1 monomer showed poor reactivity under the evaluated polymerization method. The Azo 2 monomer was used in the block copolymerization with polystyrene by the normal ATRP methodology. Several polystyrene macroinitiators were prepared with molecular weights of 10, 20 and 30 k g/mol. The end functionality was increased by the addition of 0.1 equivalents of copper II chloride. Block copolymers in 30% yield and low polydispersity were synthesized by ATRP from the polystyrene macroinitiators and the azo monomer. The block copolymer exhibits good photochromic activity.