Enhanced dissolution of copolymers bearing photobase‐ or photoacid‐generating groups in polar solvents by photochemical formation of ionic pairs

Abstract

Solubility changes in the irradiation of copolymers bearing photoacid‐ or photobase‐generating groups and low molecular weight photobase generators (PBGs) or photoacid generators (PAGs) were investigated. Copolymers bearing acyloxyimino (AOI) groups were used as those generating pendant amino groups photochemically. Copolymers bearing o‐nitrobenzyloxycarbonyl and imino sulfonate groups were used as those generating carboxy and sulfo groups, respectively. The solubility of copolymers bearing AOI groups into polar solvents was enhanced by added PAGs such as β‐keto sulfones or imino sulfonates after irradiation. A similar enhancement was observed in copolymers bearing o‐nitrobenzyloxycarbonyl groups in the presence of PBGs such as oxime esters or o‐nitrobenzyl carbamates. These results showed that the formation of acid–base pairs on irradiation was effective for dissolution into polar solvents. Copolymers bearing imino sulfonate groups showed a high solubility, and no such enhancement was observed by PBG. Films of copolymers bearing β‐keto sulfone groups became insoluble because of crosslinking. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1708–1715, 2001

Photoinduced Depolymerization of Poly(olefin sulfone)s Possessing Photobase Generating Groups in the Side Chain

“…The photobase generating moieties incorporated in this study exhibit a decarboxylation reaction when irradiated with UV light and When polymer 1 film is exposed to UV light, an o-acyl oxime group is photochemically converted into an imino group, which can be changed to an amino group by immersing the polymer film in a dilute HCl solution. 23,24 It has been reported that the photochemical reaction of the o-acyl oxime group occurs most efficiently with 365 nm irradiation in the presence of benzophenone. 23 A film of polymer 1 doped with 10 wt % benzophenone was irradiated with 365 nm light.…”

Photoinduced Depolymerization of Poly(olefin sulfone)s Possessing Photobase Generating Groups in the Side Chain

“…The photobase generating moieties incorporated in this study exhibit a decarboxylation reaction when irradiated with UV light and When polymer 1 film is exposed to UV light, an o-acyl oxime group is photochemically converted into an imino group, which can be changed to an amino group by immersing the polymer film in a dilute HCl solution. 23,24 It has been reported that the photochemical reaction of the o-acyl oxime group occurs most efficiently with 365 nm irradiation in the presence of benzophenone. 23 A film of polymer 1 doped with 10 wt % benzophenone was irradiated with 365 nm light.…”

Photoinduced Depolymerization of Poly(olefin sulfone)s Possessing Photobase Generating Groups in the Side Chain

“…The photobase generating moieties incorporated in this study exhibit a decarboxylation reaction when irradiated with UV light and When polymer 1 film is exposed to UV light, an o-acyl oxime group is photochemically converted into an imino group, which can be changed to an amino group by immersing the polymer film in a dilute HCl solution. 23,24 It has been reported that the photochemical reaction of the o-acyl oxime group occurs most efficiently with 365 nm irradiation in the presence of benzophenone. 23 A film of polymer 1 doped with 10 wt % benzophenone was irradiated with 365 nm light.…”

Photoinduced Depolymerization of Poly(olefin sulfone)s Possessing Photobase Generating Groups in the Side Chain

“…The photobase generating moieties incorporated in this study exhibit a decarboxylation reaction when irradiated with UV light and When polymer 1 film is exposed to UV light, an o-acyl oxime group is photochemically converted into an imino group, which can be changed to an amino group by immersing the polymer film in a dilute HCl solution. 23,24 It has been reported that the photochemical reaction of the o-acyl oxime group occurs most efficiently with 365 nm irradiation in the presence of benzophenone. 23 A film of polymer 1 doped with 10 wt % benzophenone was irradiated with 365 nm light.…”