Room Temperature Phosphorescent (RTP) Thermoplastic Elastomers with Dual and Variable RTP Emission, Photo‐Patterning Memory Effect, and Dynamic Deformation RTP Response

Abstract

Room temperature phosphorescent (RTP) polymers have advantages of strength, toughness, and processing and application flexibility over organic small molecular crystals, but the current RTP polymers are all from rigid plastics and involve chemical linkage and hydrogen and ionic bonds, and thermoplastic RTP elastomer has not been attempted and realized. Moreover, solution-processed films by simply mixing polymers and organic RTP materials can only show weak and single blue RTP. Here it is presented that such elastomer films, once thermomechanically plasticized, can emit bright and long-lived dual RTP. Moreover, they exhibit photo-activation memory effect, variable RTP colors and dynamic deformation RTP response. These results reveal that thermoplasticizing has altered the dispersion states and micro-environment of RTP molecules in matrix, and the cohesion of elastic polymer itself can also greatly restrict non-radiative relaxations to boost both blue mono-molecular and yellow micro-crystalline RTP. This work provides an effective and versatile processing strategy for tuning and enhancing the RTP properties of doped RTP polymers.

Aggregation-Induced Delayed Fluorescence and Phosphorescence from Hot Excitons via Suppression of Kasha’s Rule in a Stimuli-Active Molecular Rotor

“…However, two simultaneous emission enhancements and switching phenomena for BT2O3Cz and BT2O6Cz were observed under horizontal mechanical stress to the film, akin to the bulk solid crystals mechanoresponsive behavior (Figure 5H,I). 60,61 Upon mechanical stretching, both the emitters exhibited enhanced PL emission, and their single-molecular phosphorescence emission from the amorphous polymer matrix was found to be at 585 and 650 nm (Figure 5J,K). Notably, BT2O6Cz showed intense phosphorescence due to high-order noncovalent interactions with long alkyl chains that rigidified the elastomer more effectively.…”

Multicolor-tunable room-temperature afterglow and circularly polarized luminescence in chirality-induced coordination assemblies

“…This indicates that no intermolecular charge transfer occurs in aggregates. 33,34 It should be pointed out that no phosphorescence emission was detected by the delayed photoluminescence spectra, except in 1 × 10 −2 M chloroform (Fig. S15 †).…”

Rational molecular and doping strategies to obtain organic polymers with ultralong RTP

“…Among them, organic-doped RTP polymers are attracting much attention due to their economy, good processability, biocompatibility, and diverse mechanical properties. [1][2][3][4][5] Polymers rich in hydrogen bonds such as polyvinyl alcohol (PVA) and poly-acrylamide (PAM) have been widely used as matrices in view of their high rigidity and strong interactions with the polar groups of organic dopant molecules. [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] Utilizing PVA as a matrix, Huang et al obtained a RTP lifetime of 3.16 s by doping carbazol-9-ylacetic acid, 18 Yang et al doped triphenylen-2-yl-boronic acid and realized a RTP lifetime of 3.29 s. 21 Li et al doped simple bi-and terphenylboronic acids and achieved RTP lifetimes of 2.34-2.43 s. 6 Chen et al co-polymerized 9-vinylcarbazole and acrylamide and realized a RTP lifetime of 4.2 s. 19 These are the longest-lived RTP lifetimes obtained so far.…”

“…Moreover, the effect of comparable-structure dopants and material aggregates on organic RTP properties is incompletely understood. 1,20,22–24…”