Wavelength-gated photoreversible polymerization and topology control.

ABSTRACT: We exploit the wavelength dependence of [2 + 2] photocycloadditions and -reversions of styrylpyrene to exert unprecedented control over the photoreversible polymerization and topology of telechelic building blocks. Blue light (λ max = 460 nm) initiates a catalyst-free polymerization yielding high molar mass polymers (M n = 60 000 g mol-1), which are stable at wavelengths exceeding 430 nm, yet highly responsive to shorter wavelengths. UVB irradiation (λ max = 330 nm) induces a rapid depolymerization affording linear oligomers, whereas violet light (λ max = 410 nm) generates cyclic entities. Thus, different colors of light allow switching between a depolymerization that either proceeds through cyclic or linear topologies. The light-controlled topology formation was evidenced by correlation o

SUBMITTER: Frisch H 

PROVIDER: S-EPMC7069517 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature