Chiral Polymers Based on Vinyl[2.2]paracyclophane and Their Application as CPL Emitters

Abstract

Chiral molecules are integral to various biological and artificial systems, influencing processes from chemical production to optical activities. In this study, we explore the potential of chiral vinyl[2.2]paracyclophane (vinyl-PCP) as a monomer for the synthesis of homopolymers and copolymers with styrene. We achieved polymerization through anionic, cationic, and radical methods. The resulting polymers demonstrated significant chiral properties, even in copolymers with small fractions of the chiral monomer. Further, we developed a polymerizable vinyl emitter from 10-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-9,9-dimethyl-9,10-dihydroacridine (DMAC-TRZ) through a two-step synthesis with an overall yield of 48%. Copolymerization with chiral vinyl-PCP resulted in emissive polymers that demonstrated circularly polarized luminescence (CPL) properties. The inclusion of the chiral PCP monomer, acting both as a host material and the source of chirality for CPL, enhanced the photoluminescence quantum yield (PLQY) to 47.2% in N2 at 5–10% emitter content, compared to 26.8% for the pure emitter polymer. CPL-active polymers show clear mirror-image Cotton effects at 240 nm and 267 nm and dissymmetry factors around +2 × 10−4 and −1 × 10−4. This self-hosting effect of PCP monomers underscores the potential of chiral vinyl-PCP for advanced functional materials in optical communication and bio-responsive imaging.