934762-26-2Relevant articles and documents
Synthesis, structures and multifunctional sensory properties of poly[2,7-(9,9-dihexylfluorene)]-block-poly[2-(dimethylamino)ethyl methacrylate] rod-coil diblock copolymers
Lin, Sung-Tso,Tung, Yi-Chih,Chen, Wen-Chang
, p. 3985 - 3992 (2008)
The synthesis, structures and multifunctional sensory properties of amphiphilic poly[2,7-(9,9-dihexylfluorene)]-block-poly[2-(dimethylamino)ethyl methacrylate] (PF-b-PDMAEMA) rod-coil diblock copolymers are reported. The new copolymers, with PDMAEMA coil lengths of 31, 45, 93 and 185 repeating units, were synthesized by atom transfer radical polymerization. The surface structures and photophysical properties of the synthesized polymers were studied through the variation of solvent composition (water-THF), temperature, and pH. The PF7-b-PDMAEMA45 structure changed from spheres to separate cylinders, bundles of cylinders and spiral-shaped micelles as the solvent composition changed from 0 to 90 wt% water in THF. However, the long-range order structure of spiral-shaped loops was not observed at a long coil length. The micellar aggregates of PF7-b-PDMAEMA45 in water showed a reversible surface structure transformation from cylinder-bundles to spheres on heating from 25 to 75 °C. The variation of the micelle size with temperature was judged to be similar from both atomic force microscopy (AFM) and dynamic light scattering (DLS) measurements. The intermolecular PF aggregations led to fluorescence quenching and a blue-shift in the absorption spectra of the block copolymer as the water content increased. The photoluminescence (PL) intensity of PF7-b-PDMAEMA45 in water was thermoreversible based on its lower critical solution temperature. The PL characteristics suggested the new copolymers behave as an on/off fluorescence indicator of temperature or pH, with a reversible on-off profile at an elevated temperature in water: the pH-fluorescence intensity profile switched from off-on to on-off as the temperature increased. The present study suggests that PF-b-PDMAEMA copolymers have potential applications as multifunctional sensory materials toward solvent, temperature, and pH.
Highly ordered luminescent microporous films prepared from crystalline conjugated rod-coil diblock copolymers of PF-b-PSA and their superhydrophobic characteristics
Chiu, Yu-Cheng,Kuo, Chi-Ching,Lin, Chih-Jung,Chen, Wen-Chang
, p. 9350 - 9358 (2011)
We have successfully prepared three crystalline conjugated rod-coil diblock copolymers of poly[2,7-(9,9-dihexylfluorene)]-block-poly(stearyl acrylate) (PF-b-PSA), PF7-b-PSA64, PF7-b-PSA 93, and PF7-b-PSA166, via the combination of a Suzuki coupling reaction and atom transfer radical polymerization. The crystalline comb-like PSA coil segment effectively formed the highly ordered microporous films through a "breath figure" (BF) process. On the other hand, the blue-emission band of the PF block was blue-shifting and became narrower as the PSA block was increased. The effects of block ratio, humidity, and solution concentrations on the porous structures were studied. The longer PSA block length, larger humidity, and higher copolymer concentration formed a more regular PF-b-PSA microporous structure. The images of SEM and scanning laser confocal microscope of the PF7-b-PSA166 microporous film showed that all bubbles were independent and perfectly monodisperse with a pore diameter ca. 1.85 μm. Furthermore, a rod-co-valley-like structure exhibited superhydrophobicity (contact angle up to 163 ± 0.3°), which was obtained from the peeled skin layer of the ordered PF7-b- PSA166 microporous surface. The experimental results revealed that multifunctional ordered microporous films could be successfully prepared from crystalline conjugated rod-coil block copolymers.
Synthesis of Luminescent Polystyrene with φ-Conjugated Pendant
Wang, Feng,Zhu, Cai-Xia
, p. 5700 - 5702 (2013)
One novel polystyrene-based copolymer (PS-PF) with φ-conjugated unit (fluorneyl and phenyl rings) as pendant was designed and synthesized using radical polymerization method and initiated by AIBN (2,2'- azobisisobutyronitrile) from the new functional mono
Self-assembled structures in rod-coil block copolymers with hydrogen-bonded amphiphiles
Sun, Han-Sheng,Lee, Chia-Hao,Lai, Chia-Sheng,Chen, Hsin-Lung,Tung, Shih-Huang,Chen, Wen-Chang
, p. 4198 - 4206 (2011)
We report the synthesis and the self-assembled morphologies of a series of new rod-coil diblock copolymers, poly[2,7-(9,9-dihexylfluorene)]-b-poly(4- vinylpyridine) (PF-b-P4VP). The rod-coil diblock copolymers were synthesized via Suzuki coupling reaction and living anionic polymerization. Probing by transmission electron microscopy, small-angle X-ray scattering and atomic force microscopy, we found that the microphase separation varies from lamellar to cylindrical and then to spherical, depending on the length of P4VP blocks. The P4VP coil blocks were further hydrogen-bonded with 3-pentadecylphenol (PDP) to form rod-comb block copolymers. Similar to conventional coil-coil block copolymers-based supramolecules, the incorporation of PDP transforms the morphologies from lamellar to cylindrical or from cylindrical to spherical due to the increase of volume fraction of P4VP(PDP) comb blocks. The strategy described here can be used to tune the self-assembled structures of rod-coil block copolymers.