Polymers of Dibenzothiophenes

Dibenzothiophene derivatives have been used as co-catalysts in the addition polymerization of vinyl and diene monomers. Dibenzothiophene itself, in conjunction with vanadium oxychloride, is effective in initiating the polymerization of isobutylene, - although when incorporated in a Ziegler catalyst system, competition between donor and monomer for the most electrophilic sites results in deactivation of the catalyst. Despite the fact that 2-vinyl- - - and 4-vinyldibenzothiophene - readily undergo thermal polymerization, 

809 British Thompson Houston Co. Ltd., British Patent 661,503 (1951) Chem. Abstr. 46, 5365 (1952). 

Self-condensation of the potassium salt of 2-hydroxy-8-bromodibenzo-thiophene 5,5-dioxide in dimethyl sulfone gives a thermoplastic polymer of unit structure 150.  

521 Laboratories frangais de chimiotherapie, French Patent 978,499 (1951) Chem. Abstr. 48, 2772 (1953). 

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