Application of Solubility Parameters in 1,3:2,4-Bis(3,4-dimethylbenzylidene)sorbitol Organogel in Binary Organic Mixtures

详细信息    查看全文

• 作者：Huahua Shen ; Libo Niu ; Kaiqi Fan ; Jingjing Li ; Xidong Guan ; Jian Song
• 刊名：Langmuir
• 出版年：2014
• 出版时间：August 5, 2014
• 年：2014
• 卷：30
• 期：30
• 页码：9176-9182
• 全文大小：357K
• ISSN：1520-5827

文摘

The gelation behavior of 1,3:2,4-bis(3,4-dimethylbenzylidene)sorbitol (DMDBS) in binary solvents has been systematically investigated. DMDBS is soluble in DMSO and insoluble in toluene (apolar) or 1-propanol (polar). When DMSO is added to a poor solvent at a certain volume fraction, DMDBS forms an organogel in the mixed solvent. With increasing DMSO content, the minimum gelation concentration increases and the gel-to-sol transition temperature decreases in both systems. However, compared with those in toluene鈥揇MSO mixtures, the gelation ability and thermal stability are better in 1-propanol鈥揇MSO mixtures. Scanning electron microscopy images reveal that the gelators aggregate to form three-dimensional networks. X-ray diffraction shows that the gel has a lamellar structure, which is different from the structure of the precipitate. Fourier transform infrared results reveal H-bonding is the main driving force for self-aggregation and indicate that stronger H-bonding interactions exist between gelators in 1-propanol鈥揇MSO mixtures in contrast with toluene鈥揇MSO mixtures. Attempts have been taken to correlate solvent parameters to gelation behavior in binary solvents. A Teas plot exhibits distinctly different solvent zones in the studied mixed solvents. The polar parameter (未_p) indicates a narrow favorable domain for gel formation in the range of 1.64鈥?.99 MPa^1/2 for some apolar solvent鈥揇MSO mixtures. The hydrogen-bonding parameter (未_h) predicts that gelation occurs for values of 14.00鈥?6.50 MPa^1/2 for some polar solvent鈥揇MSO mixtures. The result may have potential applications in predicting the gelation behavior of 1,3:2,4-di-O-benzylidene-d-sorbitol derivatives in mixed solvents.