Condensative chain polymerization. II. Preferential esterification of propagating end group in Pd-catalyzed CO-insertion polycondensation of 4-bromophenol derivatives
✍ Scribed by Tsutomu Yokozawa; Hirokazu Shimura
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 223 KB
- Volume
- 37
- Category
- Article
- ISSN
- 0887-624X
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✦ Synopsis
For a development of condensative chain polymerization where polycondensation proceeds from an initiator in a chain polymerization manner to yield polymer with a defined molecular weight and a narrow molecular weight distribution, the Pd-catalyzed polycondensation of 4-bromophenol derivatives with CO is studied. Model reactions showed that monomer reacted the polymer terminal Br preferentially compared to the monomer Br, but that the ester exchange reaction of polymer backbone with monomer phenoxide occurred in some extent. In the polymerization of 4-bromo-2-n-octylphenol with CO using 4-bromo-2,6-dimethylphenyl benzoate as an initiator, the molecular weight of polymer increased in proportion to time up to 30 min. The GPC elution curves showed that oligomers were produced from the initiator.