The graft copolymerization of styrene and lignin. III. Chain transfer reactions of lignin and lignin model compounds

✍ Scribed by R. B. Phillips; W. Brown; V. Stannett

• Publisher: John Wiley and Sons
• Year: 1973
• Tongue: English
• Weight: 421 KB
• Volume: 17
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.1973.070170210

✦ Synopsis

Abstract

The effect of addition of lignin model compounds on the polymerization rate and molecular weight of polymer in the radiation‐induced polymerization of styrene was studied. Guaiacol, a model for softwood lignin, reacted slowly with styrene radicals, while 2,6‐dimethoxyphenol, a hardwood lignin model, was a much more efficient chain transfer agent. Studies with isoeugenol indicate that allylic or phenoxy radical stability in a conjugated system may terminate polymerization quite effectively. The results are discussed in the light of new and previous data with isolated lignins; they are consistent with the previously presented grafting scheme.