Red-Shifted Luminescence of Acrylonitrile-Containing Copolymers: A Matter of One Methyl Unit.

Copolymerization provides an effective approach to tune the photophysical properties of non-conventional luminescent polymers (NCLPs). In this study, we reveal the controlling of intrinsic emissions of polyacrylonitrile (PAN) copolymers by a delicate difference of secondary monomers. The introducing of methacrylate comonomers can induce a 70-nm red-shifting on the PL emission of copolymers compared with that of acrylate-containing copolymers. The mechanism of such "copolymerization induced red-shifting" in PAN copolymers was investigated. It is demonstrated that the presence of α-methyl group in the copolymers can enhance the chain rigidity and through-space conjugation (TSC) of C≡N groups, resulting in the red-shifting of emission. This article is protected by copyright. All rights reserved.