Borelli Mirko, Iasilli Giuseppe, Minei Pierpaolo, Pucci Andrea
Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via G. Moruzzi 13, 56124 Pisa, Italy.
INSTM, UdR Pisa, Via G. Moruzzi 13, 56124 Pisa, Italy.
Molecules. 2017 Aug 6;22(8):1306. doi: 10.3390/molecules22081306.
Thin films of styrene copolymers containing fluorescent molecular rotors were demonstrated to be strongly sensitive to volatile organic compounds (VOCs). Styrene copolymers of 2-[4-vinyl(1,1'-biphenyl)-4'-yl]-cyanovinyljulolidine (JCBF) were prepared with different P(STY--JCBF)(m) compositions (m% = 0.10-1.00) and molecular weights of about 12,000 g/mol. Methanol solutions of JCBF were not emissive due to the formation of the typical twisted intramolecular charge transfer (TICT) state at low viscosity regime, which formation was effectively hampered by adding progressive amounts of glycerol. The sensing performances of the spin-coated copolymer films (thickness of about 4 µm) demonstrated significant vapochromism when exposed to VOCs characterized by high vapour pressure and favourable interaction with the polymer matrix such as THF, CHCl₃ and CH₂Cl₂. The vapochromic response was also reversible and reproducible after successive exposure cycles, whereas the fluorescence variation scaled linearly with VOC concentration, thus suggesting future applications as VOC optical sensors.
含有荧光分子转子的苯乙烯共聚物薄膜被证明对挥发性有机化合物（VOCs）具有强烈的敏感性。制备了2-[4-乙烯基(1,1'-联苯)-4'-基]-氰基乙烯基久洛定（JCBF）的苯乙烯共聚物，其具有不同的P(STY--JCBF)(m)组成（m% = 0.10 - 1.00）且分子量约为12,000 g/mol。由于在低粘度状态下形成了典型的扭曲分子内电荷转移（TICT）态，JCBF的甲醇溶液不发光，而加入逐渐增加量的甘油有效地阻碍了这种态的形成。旋涂共聚物薄膜（厚度约为4 µm）在暴露于具有高蒸气压且与聚合物基体有良好相互作用的VOCs（如四氢呋喃、氯仿和二氯甲烷）时，表现出显著的变色效应。在连续暴露循环后，变色响应也是可逆且可重复的，而荧光变化与VOC浓度呈线性比例关系，因此表明其有望作为VOC光学传感器应用。
