Poly(ary1 ether ketone)s were synthesized by the reaction of 1,3-(bischlorobenzoyI)benzene or the corresponding fluoro analogue with bisphenoxides derived from either hydroquinone or 4,4- isopropylidenebiphenol (bisphenol-A). With the stronger nucleophile, obtained from bisphenol-A, and either of the dihalides, high molecular weight polymers are formed exclusively via a nucleophilic aromatic substitution (S,AR) reaction. A similar reaction leads to the formation of a high molecular weight polymer when the weaker nucleophile, derived from hydroquinone, is allowed to react with the bisfluoride. On the other hand, oligomeric products are obtained when the bischloride is treated with this weaker nucleophile. In this case, both &AR and SRNl (substitution, radical-nucleophilic, unimolecular) mechanisms are operative for the replacement of the chlorine atoms. The E&,1 pathway, which is responsible for the formation of oligomeric products, can be eliminated by the addition of a suitable radical scavenger. High molecular weight poly(ary1 ether ketone) is then formed via the S,AR mechanism.
Посилання на статтю:
Poly(aryl ether ketone) synthesis via competing S,AR and SJ reactions: I. Polymers derived from 1,3-bis(p-chlorobenzoyl)benzene and 1,3-bis(p-fluorobenzoyl)benzene with hydroquinone and 4,4-isopropylidenediphenol / R. S. Mani, 6. Zimmerman, A. Bhatnagar and D. K. Mohanty // Polymer. – 1993. – Vol 34. – P. 171-181.
