title: Fluorescent porous film modified polymer optical fiber via "click" chemistry: stable dye dispersion and trace explosive detection.
abstract: In this paper, we report a facile strategy to fabricate fluorescent porous thin film on the surface of U-bent poly(methyl methacrylate) optical fiber (U-bent POF) in situ via "click" polymerization for vapor phase sensing of explosives. Upon irradiation of evanescent UV light transmitting within the fiber under ambient condition, a porous film (POSS-thiol cross-linking film, PTCF) is synthesized on the side surface of the fiber by a thiol-ene "click" reaction of vinyl-functionalized polyhedral oligomeric silsesquioxanes (POSS-V8) and alkane dithiols. When vinyl-functionalized porphyrin, containing four allyl substituents at the periphery, is added into precursors for the polymerization, fluorescence porphyrin can be covalently bonded into the cross-linked network of PTCF. This "fastened" way reduces the aggregation-induced fluorescence self-quenching of porphyrin and enhances the physicochemical stability of the porous film on the surface of U-bent POF. Fluorescent signals of the PTCF/U-bent POF probe made by this method exhibit high fluorescence quenching toward trace TNT and DNT vapor and the highest fluorescence quenching efficiency is observed for 1, 6-hexanedimercaptan-based film. In addition, because of the presence of POSS-V8 with multi cross-linkable groups, PTCF exhibits well-organized pore network and stable dye dispersion, which not only causes fast and sensitive fluorescence quenching against vapors of nitroaromatic compounds, but also provides a repeatability of the probing performance.
authors.affiliation: CAS Key Laboratory of Soft Matter Chemistry, Collaborative Innovation Center of Chemistry for Energy Materials, Department of Polymer Science and Engineering, Anhui Key Laboratory of Optoelectronic Science and Technology, University of Science and Technology of China , Hefei, Anhui 230026, China.
authors.forename: Jiajun
authors.initials: J
authors.lastname: Ma
authors.forename: Ling
authors.initials: L
authors.lastname: Lv
authors.forename: Gang
authors.initials: G
authors.lastname: Zou
authors.forename: Qijin
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D057930:Click Chemistry; D004396:Coloring Agents / Q000737:chemistry; D053834:Explosive Agents / Q000032:analysis*; D005453:Fluorescence; D055100:Optical Fibers; D058105:Polymerization; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry*; D016062:Porosity
chemical_list: D004396:Coloring Agents; D053834:Explosive Agents; D011108:Polymers
keywords: click chemistry; explosive detection; fluorescent quenching; poly(methyl methacrylate) optical fiber; porous film