Symmetrical trisazo sequential free radical initiators having two different azo functions
Abstract
Abstract Polyazo compounds having at least one azo function different from the other azo function(s). Examples: 4-Ethoxycarbonylazo-4-cyanopentyl 4-T-BUTYLAZO-4-CYANOVALERATE; 2,2''-Azobis(2-(4-t-butylazo-y-cyanovaleroyloxy)-4-methylpentane) . Organic syntheses requiring free radical generation in two stages are carried out using as the source of sequential free radicals a polyazo compound, as defined, wherein at least one azo function is ruptured in the first stage and the remaining azo function(s) are ruptured in the second stage. Example: Styrene monomer and 4-ethoxycarbonylazo-4-cyanopentyl 4-t-butylazo-4-cyanovalerate were reacted at about 76*C. to obtain a polystyrene containing functional azo groups. The polystyrene-azo polymer was reacted with methyl methacrylate monomer at 130*C. to obtain a block copolymer of polystyrene and poly(methyl methacrylate).
Inventors
- 👤 Chester Stephen Sheppard
- 👤 Ronald Edward Macleay
Bibliographic Details
Claims Analysis
Total Claims: 3References Cited (Backward Citations)
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