Poly fluorenone-isophthalates

Fluorenone based polyesters such as poly(9,9-bis(4-hydroxyphenyl) lluorene isophthalate) (4.61), poly(9,9-biscresol fluorene isophthalate) and poly(9,9-bis(3,5-dimethyl-4-hydroxyphenyl)fluorene isophthalate) undergo, under UV irradiation, typical photo-Fries rearrangement, during which linear o-hydroxybenzophenone moieties can be formed [1346]  

Photolysis of block poly(ester-co-ethers) containing such structures as (4.62) [1022] and (4.63) [1101, 2080, 2081], show the formation of hydroperoxide 

Chain scission and crosslinking occur both in argon and in air by similar mechanisms to those described for poly(ethylene terephthalate) (cf. section 4.6.3). 

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