Control the self-assembly of fluorenone-based polycatenars by tuning chain length

Using Suzuki coupling reactions as key steps, a series of fluorenone-based polycatenars, consisting of a central 2,7-diphenyl-9-fluorenone core connected with the 3,4,5-trialkoxybenzoate unit via –COO- linkage at each side have been synthesized. Upon elongation of the terminal alkyl chain, these compounds self-assembled into mesophase sequence of Col_hex/p6mm - Cub_I/$\mathit{Pm}\overline{3}n$ in solid states as well as organogels with interesting morphologies varied from 3D helical fibers to spherical structures in solvents.     

Scalable and Robust Bio-inspired Organogel Coating by Spraying Method Towards Dynamic Anti-scaling

Scaling usually causes serious problems in daily life and industrial production. Currently, developing passive anti-scaling coatings has shown promises to overcome this problem. In this work, we fabricated a scalable and robust bio-inspired organogel(BIO) coating, showing dynamic scale resistance in the oil/brine mixture. The oil layer of the BIO coating was utilized as a barrier to inhibit scale nucleation and reduce scale adhesion. The mechanical strength of the coating was optimized by regulating nanoparticle contents. Moreover, the universality of scale resistance was demonstrated by varying the types of nanoparticles, oils and scales. Compared with commercial pipeline materials, such as copper, this BIO coating significantly reduces scale deposition after 240-h scaling test(ca. 93% reduction). Therefore, this study designs scalable and robust organogel coatings for sustainable scale resistance, which may be used for practical application in oil production.     

Effect of the End Groups and the Solvent on the Gelation of the Hybrid Materials from Poly (Vinyl Chloride) (PVC) and Oligo Phenylene Vinylene (OPV)

Abstract

The role of the end-groups of three oligophenylene vinylene (OPV) and the solvents on the hybrid materials from poly (vinyl chloride) (PVC) and the OPV are examined. The gelation of the three organogel OPVs and of the hybrid materials in bromobenzene and benzyl alcohol was characterized. The morphology, as well as the thermodynamic properties, of these OPV and hybrid materials showed that they depended mostly on the solvent and very little on the different end-groups located on the OPV backbones.     

Low molecular weight organogelators derived from threefold symmetric tricarbamates

A group of new low molecular weight organogelators based on threefold symmetric tricarbamate were synthesized and characterized. The tricarbamates with long alkyl chains were able to gelate a wide range of polar and nonpolar organic solvents such as acetonitrile and cyclohexane, generally at concentrations lower than 20 g/L. The best organogel formation was obtained using a threefold symmetric tricarbamate in n-dodecane, in which a sufficiently transparent gel was formed at the critical gelation concentration 1 g/L. Intermolecular hydrogen bonding by the tricarbamate in a nonpolar solvent benzene-d₆ was indicated by ¹H NMR spectra. Its maximum UV absorption was 11 nm higher in chloroform than in n-dodecane, and this red shift indicated increased conjugation between the benzene core and the carbamate substituents, which confirmed a change in its conformation from nonpolar to polar solvent. The self-assembling behavior of the tricarbamate in dilute solutions was investigated by TEM. Fiber-like networks were observed in a large range of solution concentrations.     

Novel four-hydrogen-bond assembled oligoamide dimer with pyrazoline moieties and its photoluminescent properties

In this paper,the synthesis and characterization of a triarylpyrazoline modified four-H-bonded molecular duplex are described. Its molecular structure has been confirmed by ~1H NMR and ESI-MS.The duplex emits strong pure blue light peaking at 448 and 452 nm under UV photoexcitation in solution and solid state,respectively,and its relative photoluminescence quantum efficiency in solution is determined as 0.778 using quinine sulfate as reference.In concentration of>40 mmol/L,the duplex can gelate DMSO, and...     

Synthesis of reversible fluorescent organogel containing 2-(2′-hydroxyphenyl)benzoxazole: fluorescence enhancement upon gelation and detecting property for nerve gas simulant

A new low molecular mass organogelator 1 containing 2-(2′-hydroxyphenyl)benzoxazole (HPB) group with long alkyl chain was synthesized by the reaction with 5-amino-2-(2′-hydroxy-4′-methylphenyl)benzoxazole and dodecyl isocyanate in THF at room temperature. The reversible gelation ability of 1 was investigated using a heating-cooling method in various organic solvents. The stable organogel was formed from carbon tetrachloride or from cyclohexane at the concentration as low as 0.9%. The self-assembled supramolecular gel structure formed by non-covalent bonding was confirmed with field emission-scanning electron microscope (FE-SEM) exhibiting fibril- or ribbon-shaped structure depending on the solvent used. Regarding the aggregation-induced emission enhancement (AIEE) phenomenon, the optical properties were investigated in its solution and gelled state. The detecting properties of resulting organogel toward nerve gas simulant were monitored by UV-vis and fluorescence spectroscopy. Both color change from colorless to greenish yellow and disruption of gel structure resulting from alteration in intermolecular forces were observed upon the exposure to nerve gas simulant.     

荧光探针法研究可聚合有机分子(BMDM)/二苯醚的凝胶化过程

用荧光素作荧光探针 ,研究了可聚合凝胶因子 4,4′ 二 (α 甲基丙烯酰氧基 1 ,3 亚乙氧基羰基丙酰氨基 )二苯甲烷 (BMDM)在二苯醚的凝胶化过程中的聚集状态 .研究结果发现 ,与荧光素在二苯醚溶液中的荧光光谱相比 ,在凝胶中出现了 1 0～2 5nm的红移 ;而且发现分子凝胶的凝胶化时间随着BMDM浓度的增加而减小 .偏振荧光法研究分子凝胶的取向发现 ,该分子凝胶的形成过程是从各向同性的溶液(P0 =0 )向各向异性的溶胶 (P>0 )转变 ,再向各向同性的凝胶 (Pgel≈ 0 )转变的过程     

Glucofuranose derivatives as a library for designing and investigating low molecular mass organogelators

We designed and synthesized a class of saccharide-based gelators having three free OH groups in the glucofuranose fragment. The gelating abilities of fourteen compounds were examined to systematically study the influence of the hydrophobic fragment connected to the C2′ carbon. Also the correlation between the saccharide crystal structure and its gelating properties was examined, showing limited usefulness in this particular case. SEM observations were carried out in order to investigate the hierarchical structure of xerogels and changes depending on different gel concentration.     

电场驱动的高分子凝胶

本文较系统地阐述了电场驱动的高分子水凝胶、有机凝胶的响应机理，并扼要介绍了此类凝胶应用的最新进展。     

The triazine ring as a scaffold for the synthesis of new organogelators

The synthesis of new organogelators based on a triazine nucleus is described together with the analysis of the properties of the main compound 15. This compound revealed an efficient organogelator in both polar and apolar solvents and represents a promising precursor of other functionalized organogelators.