title: Salt Tunable Rheology of Thixotropic Supramolecular Organogels and Their Applications for Crystallization of Organic Semiconductors.
abstract: Physical gelation behaviors of a series of novel bisurea-based derivatives bearing fatty alkyl tertiary amine moieties have been explored in water and common organic solvents. One of these amines exhibits very good thixotropic gels in apolar aromatic solvents (e.g., xylenes). The corresponding sol-gel transition is instantaneous and could be repeated for at least 50 cycles. Interestingly, the elasticity and strength of the resulting gels can be remarkably enhanced initially by the addition of a trace amount of tetrabutylammonium acetate (TBA) followed by a subsequent drop with further salt addition. Temperature-dependent1H NMR confirmed that hydrogen bonding is the main driving force for the physical gelation. TEM, rheology,1H NMR titration, and examination of critical gelation concentration (CGC) reveal that the phenomenon is due to the dominated effects, the salting out effect at lower TBA concentration, or the anion-urea hydrogen bonding at higher TBA concentration. Furthermore, the obtained transparent gels in this work can be used as good media for growing crystals of several organic semiconductors.
authors: Key Laboratory of Applied Surface and Colloid Chemistry (Ministry of Education), School of Chemistry and Chemical Engineering, Shaanxi Normal University , No. 620, West Chang'an Avenue, Chang'an District, Xi'an 710119, People's Republic of China.
authors: Sheng
authors: S
authors: Gao
authors: Key Laboratory of Applied Surface and Colloid Chemistry (Ministry of Education), School of Chemistry and Chemical Engineering, Shaanxi Normal University , No. 620, West Chang'an Avenue, Chang'an District, Xi'an 710119, People's Republic of China.
authors: Suansuan
authors: S
authors: Wang
authors: Key Laboratory of Applied Surface and Colloid Chemistry (Ministry of Education), School of Chemistry and Chemical Engineering, Shaanxi Normal University , No. 620, West Chang'an Avenue, Chang'an District, Xi'an 710119, People's Republic of China.
authors: Jing
authors: J
authors: Ma
authors: Key Laboratory of Applied Surface and Colloid Chemistry (Ministry of Education), School of Chemistry and Chemical Engineering, Shaanxi Normal University , No. 620, West Chang'an Avenue, Chang'an District, Xi'an 710119, People's Republic of China.
authors: Ying
authors: Y
authors: Wu
authors: Key Laboratory of Applied Surface and Colloid Chemistry (Ministry of Education), School of Chemistry and Chemical Engineering, Shaanxi Normal University , No. 620, West Chang'an Avenue, Chang'an District, Xi'an 710119, People's Republic of China.
authors: Xuwei
authors: X
authors: Fu
authors: Key Laboratory of Applied Surface and Colloid Chemistry (Ministry of Education), School of Chemistry and Chemical Engineering, Shaanxi Normal University , No. 620, West Chang'an Avenue, Chang'an District, Xi'an 710119, People's Republic of China.
authors: Ravi Kumar
authors: RK
authors: Marella
authors: Key Laboratory of Applied Surface and Colloid Chemistry (Ministry of Education), School of Chemistry and Chemical Engineering, Shaanxi Normal University , No. 620, West Chang'an Avenue, Chang'an District, Xi'an 710119, People's Republic of China.
authors: Kaiqiang
authors: K
authors: Liu
authors: Key Laboratory of Applied Surface and Colloid Chemistry (Ministry of Education), School of Chemistry and Chemical Engineering, Shaanxi Normal University , No. 620, West Chang'an Avenue, Chang'an District, Xi'an 710119, People's Republic of China.
authors: Yu
authors: Y
authors: Fang