Fig. 9. ¹H NMR spectrum of PMA synthesized by visible light-initiated polymerization with Xe lamp irradiation at ambient temperature. [MA]₀ = 1.0 M, [MA]₀/[(salen)Co–CO₂CH₃]₀ = 200/1, conversion = 50%. M _n,GPC = 10 300, M _n,th = 9270, M _n,NMR = 9530, M _w/M _n = 1.10. M _n,th = M _{w( I )} + M _w(MA) × ratio × conv. (%); M _n,NMR = I ^2.3ppm/(I ^7.9ppm/2) × M _w(MA) + M _{w( I )}, where I ^2.3ppm and I ^7.9ppm are the integrals of the signals at δ 2.3 ppm and 7.9 ppm corresponding to the methane group of MA and the imine group of salen, respectively.