{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,24]],"date-time":"2026-10-24T01:45:45Z","timestamp":1792806345895,"version":"4.5.0"},"reference-count":33,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,2,16]],"date-time":"2026-02-16T00:00:00Z","timestamp":1771200000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Hainan University Start-up Funding for Scientific Research","award":["RZ2200001326"],"award-info":[{"award-number":["RZ2200001326"]}],"id":[{"id":"https:\/\/ror.org\/03q648j11","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Constructing a donor\u2013acceptor (D\u2013A) architecture in luminescent radicals is an effective strategy for enhancing luminescent properties. However, further structural modification of the radical core through the simple substitutions in the framework of D\u2013A radicals remains relatively underexplored. Herein, we synthesized two radical derivatives TTM-Mes-Cz-Mz and TTM-Mes-Dpa-Mz through modification of the TTM unit of TTM-Cz and TTM-Dpa with imidazole and mesitylene groups. These radical derivatives exhibited high photoluminescence quantum efficiency (PLQE) (80% for TTM-Mes-Cz-Mz and 39% for TTM-Mes-Dpa-Mz) and photostability. The radical units were further covalently grafted onto the polymer chains to synthesize ionic radical polymers LT-Cz and LT-Dpa. LT-Cz and LT-Dpa showed PLQE of 39% and 29% in a solid state, respectively. Furthermore, the polymers exhibited solvent-responsive luminescence with dichloromethane and tetrahydrofuran. A significant redshift in emission wavelength and decrease in emission intensity were observed. The polymers could return to their initial state with solvent evaporation. This work advances the exploration of the role of simple substituent modifications in D\u2013A radical systems, thereby enabling highly efficient luminescence in both small-molecule radicals and radical polymers.<\/jats:p>","DOI":"10.3390\/molecules31040681","type":"journal-article","created":{"date-parts":[[2026,2,16]],"date-time":"2026-02-16T14:55:47Z","timestamp":1771253747000},"page":"681","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Simple Substitutions into Donor\u2013Acceptor Radicals to Construct Highly Luminescent Radicals and Solvent-Responsive Ionic Radical Polymers"],"prefix":"10.3390","volume":"31","author":[{"given":"Shenghui","family":"He","sequence":"first","affiliation":[{"name":"School of Materials Science and Engineering, Hainan University, No 58, Renmin Avenue, Haikou 570228, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhenyu","family":"Li","sequence":"additional","affiliation":[{"name":"School of Environmental and Material Engineering, Yantai University, Yantai 264005, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lintao","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Materials Science and Engineering, Hainan University, No 58, Renmin Avenue, Haikou 570228, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e202423470","DOI":"10.1002\/anie.202423470","article-title":"Stable Luminescent Diradicals: The Emergence and Potential Applications","volume":"64","author":"Zhu","year":"2025","journal-title":"Angew. 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