Synthesis and Characterization of Polyurethanes of 2,4-Toluene Di Isocyanate with Multifunctional Chromophores in the Main Chain

摘要

A series of photosensitive polyurethanes with multifunctional chromophores, viz. bis (azo) and bis (o-nitrobenzyl) groups, were synthesized by polyaddition reactions of diols such as bis (4-hydroxyphenylazo)-2,2 -dinitrodiphenylmethane, 4-hy-droxy-3-methylphenylazo-4 -hydroxy-phenylazo-2,2'— dinitrodiphenyl-methane and bis (4-hydroxy-S-methylphenylazo)-2,2'-dinitro-diphenylmethane with 2,4-toluene diisocyanate (TDI), in dimethyl acetamide (DMAc) in the presence of di-n-butyltin dilaurate (DBTDL) ascatalyst. All of them were characterized by IR, UV-VIS, H NMR and ~(13)C NMR spectra, DSC and GPC.