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[0073] In another preferred embodiment, the base polymer may further comprise recurring units ( d) selected from units derived from indene, benzofuran, benzothiophene, acenaph› thylene, chromone, coumarin, and norbonadiene, or deriva› tives thereof. Suitable monomers are exemplified below. 

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[0074] Furthermore, recurring units (e) may be incorpo› rated in the base polymer, which are derived from styrene, vinylnaphthalene, vinylanthracene, vinylpyrene, methyl› eneindene, vinylpyridine, and vinylcarbazole. 

[0075] In a further embodiment, recurring units (f) derived from an onium salt having a polymerizable unsaturated bond 

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