{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T18:08:50Z","timestamp":1785434930065,"version":"3.56.0"},"reference-count":34,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T00:00:00Z","timestamp":1776297600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100016316","name":"Changzhou Vocational Institute of Engineering","doi-asserted-by":"crossref","award":["11130800225001"],"award-info":[{"award-number":["11130800225001"]}],"id":[{"id":"10.13039\/501100016316","id-type":"DOI","asserted-by":"crossref"}]},{"award":["11130800225001"],"award-info":[{"award-number":["11130800225001"]}],"id":[{"id":"https:\/\/ror.org\/03pza9p08","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>Poly(9,9-di-n-octylfluorene) (PFO) suffers from interchain aggregation, which degrades its blue spectral stability and charge transport. To address this, a series of rod-coil diblock copolymers (PFO-b-PMMAs) with varying poly(methyl methacrylate) (PMMA) chain lengths were synthesized via Steglich coupling. The non-conjugated PMMA blocks act as bulky steric spacers in the solid state, effectively suppressing detrimental PFO aggregation and enhancing pure blue emission stability. Furthermore, moderate PMMA blocks (PFO-b-PMMA1 and PFO-b-PMMA2) promote favorable \u03b2-phase formation and ordered crystalline packing. This microstructural optimization yields a maximum electron mobility of 1.98 \u00d7 10\u22126 cm2\/(V\u00b7s) for PFO-b-PMMA2, markedly higher than the PFO-2 homopolymer (4.13 \u00d7 10\u22127 cm2\/(V\u00b7s)). However, an overlong PMMA block (PFO-b-PMMA3) introduces excessive steric hindrance (Tg = 66 \u00b0C) that disrupts crystallization, acting as an insulating barrier that reduces mobility. Thus, precisely tuning the non-conjugated block length effectively maximizes both the blue spectral stability and electron transport capabilities of PFO-based materials.<\/jats:p>","DOI":"10.3390\/mi17040487","type":"journal-article","created":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T07:48:12Z","timestamp":1776412092000},"page":"487","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Synthesis, Electron Transport Behavior, and Enhanced Blue Light Stability of Polyfluorene-Poly(Methyl Methacrylate) Diblock Copolymers"],"prefix":"10.3390","volume":"17","author":[{"given":"Ruoyu","family":"Jiang","sequence":"first","affiliation":[{"name":"Department of Chemical Engineering and Pharmaceutical Engineering, Changzhou Vocational Institute of Engineering, Changzhou 213164, China"},{"name":"Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Nakacho, Koganei-shi 184-8588, Tokyo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1827-542X","authenticated-orcid":false,"given":"Changchun","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering and Pharmaceutical Engineering, Changzhou Vocational Institute of Engineering, Changzhou 213164, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jin","family":"Cheng","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering and Pharmaceutical Engineering, Changzhou Vocational Institute of Engineering, Changzhou 213164, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9938-6748","authenticated-orcid":false,"given":"Kenji","family":"Ogino","sequence":"additional","affiliation":[{"name":"Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Nakacho, Koganei-shi 184-8588, Tokyo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"539","DOI":"10.1038\/347539a0","article-title":"Light-emitting diodes based on conjugated polymers","volume":"347","author":"Burroughes","year":"1990","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"121","DOI":"10.1038\/16393","article-title":"Electroluminescence in conjugated polymers","volume":"397","author":"Friend","year":"1999","journal-title":"Nature"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"7990","DOI":"10.1038\/s41467-024-50358-1","article-title":"Intrinsically stretchable fully \u03c0-conjugated polymer film via fluid conjugated molecular external-plasticizing for flexible light-emitting diodes","volume":"15","author":"Zhuo","year":"2024","journal-title":"Nat. Commun."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"2411449","DOI":"10.1002\/adma.202411449","article-title":"Plasticizer design principle of \u201cLike Dissolves Like\u201d: Semiconductor fluid plasticized stretchable fully \u03c0-conjugated polymers films for uniform large-area and flexible deep-blue polymer light-emitting diodes","volume":"36","author":"Ma","year":"2024","journal-title":"Adv. Mater."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"6634","DOI":"10.1021\/acs.macromol.5c00478","article-title":"Intrinsically stretchable electroluminescent elastomers based on fully conjugated backbones for organic light-emitting diodes","volume":"58","author":"Wan","year":"2025","journal-title":"Macromolecules"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"7416","DOI":"10.1021\/ja9615233","article-title":"Efficient photoluminescence and electroluminescence from a soluble polyfluorene","volume":"118","author":"Pei","year":"1996","journal-title":"J. Am. Chem. Soc."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"629","DOI":"10.1063\/1.121878","article-title":"High brightness and efficiency blue light-emitting polymer diodes","volume":"73","author":"Grice","year":"1998","journal-title":"Appl. Phys. Lett."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"8273","DOI":"10.1021\/acsnano.2c02083","article-title":"Reaching nearly 100% quantum efficiencies in thin solid films of semiconducting polymers via molecular confinements under large segmental stresses","volume":"16","author":"Lu","year":"2022","journal-title":"ACS Nano"},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Pidluzhna, A., Vembris, A., Grzibovskis, R., Zommere, M.A., Bezvikonnyi, O., Simokaitiene, J., Baronaite, M., Volyniuk, D., Grazulevicius, J.V., and Ali, A. (2024). The effect of molecular structure on the properties of fluorene derivatives for OLED applications. Molecules, 29.","DOI":"10.3390\/molecules29204918"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"111776","DOI":"10.1016\/j.optlastec.2024.111776","article-title":"Optimized dual-band amplified spontaneous emission properties of PFO and BUBD-1 blend films based on AgNPs doped buffer layers","volume":"181","author":"Xu","year":"2025","journal-title":"Opt. Laser Technol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"325","DOI":"10.1002\/adfm.200304279","article-title":"Stabilized blue emission from polyfluorene-based light-emitting diodes: Elimination of fluorenone defects","volume":"13","author":"Gong","year":"2003","journal-title":"Adv. Funct. Mater."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"8137","DOI":"10.1021\/acs.jpcc.8b01767","article-title":"Intrachain aggregates as the origin of green emission in polyfluorene studied on ensemble and single-chain level","volume":"122","author":"Nakamura","year":"2018","journal-title":"J. Phys. Chem. C"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"3042","DOI":"10.1039\/C6TC05065D","article-title":"Charge carrier trapping controlled by polymer blend phase dynamics","volume":"5","author":"Kunz","year":"2017","journal-title":"J. Mater. Chem. C"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"6380","DOI":"10.1021\/acs.chemmater.9b01211","article-title":"Electron trapping in conjugated polymers","volume":"31","author":"Abbaszadeh","year":"2019","journal-title":"Chem. Mater."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"093301","DOI":"10.1063\/1.5058195","article-title":"Efficiency enhancement of polyfluorene: Polystyrene blend light-emitting diodes by simultaneous trap dilution and \u03b2-phase formation","volume":"113","author":"Khodabakhshi","year":"2019","journal-title":"Appl. Phys. Lett."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"12890","DOI":"10.1021\/ja051891j","article-title":"Effects of packing structure on the optoelectronic and charge transport properties in poly(9,9-di-n-octylfluorene-alt-benzothiadiazole)","volume":"127","author":"Donley","year":"2005","journal-title":"J. Am. Chem. Soc."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"67","DOI":"10.1002\/adfm.200800313","article-title":"The influence of alkyl-chain length on beta-phase formation in polyfluorenes","volume":"19","author":"Bright","year":"2009","journal-title":"Adv. Funct. Mater."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"19869","DOI":"10.1039\/C4RA01616E","article-title":"Synthesis and characterization of polyfluorene-based photoelectric materials: The effect of coil segment on the spectral stability","volume":"4","author":"Li","year":"2014","journal-title":"RSC Adv."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"3820","DOI":"10.1039\/C8PY00763B","article-title":"Unraveling the stress effects on the optical properties of stretchable rod-coil polyfluorene-poly (n-butyl acrylate) block copolymer thin films","volume":"9","author":"Hsieh","year":"2018","journal-title":"Polym. Chem."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"4864","DOI":"10.1016\/j.polymer.2013.07.008","article-title":"Synthesis and self-assembly of a series of \u03c0-conjugated triblock copolymers containing polyfluorene and poly (ethylene oxide)","volume":"54","author":"Ahn","year":"2013","journal-title":"Polymer"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"SE1008","DOI":"10.35848\/1347-4065\/ac4c6b","article-title":"Synthesis and electron transporting properties of triblock copolymers consisting of polyfluorene and polystyrene","volume":"61","author":"Cheng","year":"2022","journal-title":"Jpn. J. Appl. Phys."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Cheng, J., Jiang, R., Shan, Y., Sun, H., Kanehashi, S., and Ogino, K. (2024). Synthesis and electron transporting properties of diblock copolymers consisting of polyfluorene and polystyrene. Materials, 17.","DOI":"10.3390\/ma17112694"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"23505","DOI":"10.1039\/D4RA03606A","article-title":"Polyfluorene-poly(ethylene oxide) diblock copolymers: Synthesis and electron transport behavior","volume":"14","author":"Cheng","year":"2024","journal-title":"RSC Adv."},{"key":"ref_24","first-page":"21","article-title":"Method of introducing polymethylacrylic acid to form AB2 type polyfluorene block copolymer and improving its blue light stability","volume":"42","author":"Cheng","year":"2025","journal-title":"China Synth. Resin Plast."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1882","DOI":"10.1002\/adma.200702515","article-title":"Controlled \u03b2-phase formation in poly(9,9-di-n-octylfluorene) by processing with alkyl additives","volume":"20","author":"Peet","year":"2008","journal-title":"Adv. Mater."},{"key":"ref_26","unstructured":"Ingle, J.D., and Crouch, S.R. (1988). Spectrochemical Analysis, Prentice Hall. [1st ed.]."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"153301","DOI":"10.1063\/1.4824766","article-title":"Efficient and stable deep blue polymer light-emitting devices based on \u03b2-phase poly (9, 9-dioctylfluorene)","volume":"103","author":"Zhang","year":"2013","journal-title":"Appl. Phys. Lett."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"8084","DOI":"10.1021\/acs.macromol.2c01210","article-title":"Poly(diarylfluorene) deep-blue polymer light-emitting diodes based on submicrometer-scale morphological films induced by trace \u03b2-conformation","volume":"55","author":"Sun","year":"2022","journal-title":"Macromolecules"},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Zhang, Q., Wang, P.-I., Ong, G.L., Tan, S.H., Tan, Z.W., Hii, Y.H., Wong, Y.L., Cheah, K.S., Yap, S.L., and Ong, T.S. (2019). Photophysical and electroluminescence characteristics of polyfluorene derivatives with triphenylamine. Polymers, 11.","DOI":"10.3390\/polym11050840"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"3589","DOI":"10.1039\/D1MA00141H","article-title":"Photoluminescence and electroluminescence characterization of high-performance near-infrared emitters based on 1,5-naphthyridin-4-ol-containing heteroleptic platinum(II) complexes","volume":"2","author":"Kidanu","year":"2021","journal-title":"Mater. Adv."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"946","DOI":"10.1021\/ja0031220","article-title":"Polyfluorenes with polyphenylene dendron side chains: Toward non-aggregating, light-emitting polymers","volume":"123","author":"Setayesh","year":"2001","journal-title":"J. Am. Chem. Soc."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"8755","DOI":"10.1021\/jp044202j","article-title":"Rod-coil block copolymers incorporating terfluorene segments for stable blue light emission","volume":"109","author":"Chochos","year":"2005","journal-title":"J. Phys. Chem. B"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"772","DOI":"10.1038\/pj.2010.58","article-title":"Macrostructural order and optical properties of polyfluorene-based polymer films","volume":"42","author":"Hayashi","year":"2010","journal-title":"Polym. J."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"943","DOI":"10.1002\/polb.23297","article-title":"Correlation of charge transport with structural order in highly ordered melt-crystallized poly (3-hexylthiophene) thin films","volume":"51","author":"Singh","year":"2013","journal-title":"J. Polym. Sci. Part B Polym. Phys."}],"container-title":["Micromachines"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-666X\/17\/4\/487\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T04:11:46Z","timestamp":1776917506000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-666X\/17\/4\/487"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,4,16]]},"references-count":34,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2026,4]]}},"alternative-id":["mi17040487"],"URL":"https:\/\/doi.org\/10.3390\/mi17040487","relation":{},"ISSN":["2072-666X"],"issn-type":[{"value":"2072-666X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,4,16]]}}}