设计并合成了一种新的二氟单体,该单体在2,6-二氟苯甲基和六苯基苯之间具有脂族桥。然后,由新型的二氟化物单体与疏水性聚芳醚酮主链与亲水性磺化六苯苯之间的脂肪族间隔基组成一系列新颖的六磺化聚芳醚酮(HS-PAEK-x)。 4,4′-(六氟异亚丙基)二酚和4,4′-二氟二苯甲酮通过亲核缩聚反应,随后使用氯磺酸进行后磺化。所有的聚合物通过溶剂浇铸提供坚韧,柔软和透明的膜。离子交换容量(IEC)值相对较低的膜,范围为0.87至1.42 meq g -1与Nafion 117在80°C下相比,具有良好的机械性能,合适的质子传导性(111 mS cm -1),并且具有出色的尺寸稳定性(在80°C下,最长的溶胀率为9.2%)。此外,与先前报道的具有相似主链的聚合物(例如具有侧链磺烷基的聚合物和中空芳族六磺化聚合物)相比,HS-PAEK-x在相似的IEC水平下具有更高的质子电导率,这归因于特定分子结构和改
A highly congested hexameric subphthalocyanine array was synthesized by axial chlorine-to-phenoxy substitution of a hexakis(4-hydroxyphenyl)benzene based subphthalocyanine, and photoinduced symmetry-breaking charge separation was demonstrated in polar solvent.
Influence of (2,3,4,5,6-Pentamethyl/phenyl)phenyl Scaffold: Stereoelectronic Control of the Persistence of <i>o</i>-Quinonoid Reactive Intermediates of Photochromic Chromenes
Regioisomeric photochromic chromenes 1Ch-6Ch substituted with the (2,3,4,5,6-pentamethyl/phenyl)phenyl scaffold were designed to delve into stereoelectronic effects on the spectrokinetic properties of photogenerated o-quinonoid reactive intermediates. While the latter derived from 1Ch, 2Ch, 4Ch, and 5Ch were found to exhibit notable persistence, those from 3Ch and 6Ch were found to revert rapidly at room temperature to preclude visible coloration. The intermediates of 1Ch and 2Ch were found to be marginally more stable than those of 4Ch and 5Ch, respectively, attesting to the possibility of toroidal conjugation via C-ipso-pi orbitals in the former. The rapid reversion of the intermediates of 3Ch and 6Ch is attributed to unfavorable electronic repulsion between the phenyl ring of the (pentamethyl/phenyl)phenyl scaffold and one of the lone-pairs of the o-quinonoid oxygen. Thus, the regioisomerically substituted photochromic chromenes are shown to permit control of the reversion, very rapidly as well as slowly, of the colored o-quinonoid intermediates through operation of stereoelectronic effects differently.