Preparation and Characterization of Water-Insoluble Gardenia Blue Pigment

Based on molecular simulations, the synthetic route of water-insoluble gardenia blue pigment was prepared by the reaction of genipin and L-Phenylalanine methyl ester hydrochloride. A highly purified pigment was obtained after extraction by chloroform and purification by silica gel column chromatography, and the value of color is up to 288. A study on the structural characteristics of the pigment was implemented with a scanning electron microscope, ultraviolet-visible spectrophotometer, Fourier transform infrared spectrometer, X-ray photoelectron spectrometer, and quatropde-time of flight mass spectrometer. The results showed that the surface of the pigment was largely smooth and spherical; The λmax was 607 nm, and the main functional groups include O-C=O, C=O, C-N, C=C, OH, and benzene ring; We detrained six different molecular weight and chemical structures of pigments and speculated the particular structures and formation mechanisms of three kinds of pigment, whose molecular weights are 690.1156, 720.1226, and 708.1246 Da, respectively. The pigment was only able to be dissolved in ethanol, methanol, acetone, ethyl acetate, and other strong polar organic solvents, but was not able to be dissolved in water, ethyl ether, petroleum ether, and other weak polar organic solvents. In terms of light and thermal stabilities, water-insoluble gardenia blue pigment is significantly better than water-soluble gardenia blue pigment (p < 0.05). When it is under direct light for 7 days or incubated at 80–120 °C for 24 h, the pigment residual rates were 74.90, 95.26, 88.27, and 87.72%, respectively.

Study of succinic anhydride amidation by 2-aminothiazol

The reaction between succinic anhydride and 2-aminothiazole was carried out in polar organic solvents (acetone, 1,4-dioxane, isopropanol) and in a mechanochemical reactor. By of X-ray phase analysis, IR, 1H, 13C NMR spectroscopy it was found that in both techniques of carrying out the reaction, the only product was succinamide. It was shown that the process efficiency in the mechanochemical reaction conditions is higher in comparison with the traditional solution’s synthesis. The solid-phase interaction development was proceeded during 45 days after load removed, it was especially intense in the first 10 days.

New Chemical Constituents from the Leaves and Twigs of Holoptelea integrifolia

Phytochemical examination on the different extracts of leaves and twigs of Holoptelea integrifolia (H. integrifolia) were carried out with varied polar organic solvents. The chemical constituents of crude extracts were separated and isolated by using chromatography technique and characterized by using spectroscopies of ¹H, ¹³C and 2D NMR. Two known compounds, the stigmasterol (1) and octamethylcyclohexane-1,4-dione (2), and one new compound, di-myo-inositol (3) were isolated and characterized. Chemical constituent 2 and 3 has been reported for the first time in H. integrifolia; in addition, constituent 3 was new phytochemical finding.

The wormlike micelles formed using an ionic liquid surfactant and polar organic solvents at low temperature without additives and their lubricant properties

Wormlike micelles (or reverse wormlike micelles) are flexible cylindrical chains that are normally formed in water (or a nonpolar organic solvent) at 25.0 °C or above; the formation of wormlike micelles at lower temperatures is rare.

Production of furans from C5 and C6 sugars in presence of polar organic solvents

Furfural and hydroxymethylfurfural are promising platform molecules for manufacturing chemicals and fuel components. These furanic compounds are the product of the acid‐catalyzed dehydration of sugars (e.g., xylose and glucose), components...

Retouching unvarnished acrylic emulsion paintings, a comparative study

Acrylic films have specific characteristics such as sensibility to polar organic solvents (and in some extent water) and are prone to accidental superficial alterations. Most of the necessary retouching caused by accidental alterations is directly on the film so the notion of reversibility is crucial. This is why this study is focused on retouching media that are already proven to be suitable for acrylic paintings. Those materials are then soluble in either water or aliphatic hydrocarbons. The tested materials are Aquazol® 200 and 500, Klucel® G, gum Arabic, and Regalrez® 1094 mixed with pigments. Ready to use materials (Aquacryl®, QOR®, and Winsor & Newton® watercolours) were also tested. Various criteria were examined: first, all the materials were tested unpigmented and mixed with titanium white. Then, their gloss and colour change were measured, to see which material is more prone to produce matte films. A set of samples were then exposed to artificial light aging, and another set exposed to high relative humidity in order to isolate the impact of light and humidity on the gloss and colour of the resins (like yellowing) and observe how the retouching could behave in poor conservation conditions. Empirical tests were also conducted: the resins were mixed with five different pigments to see difference in opacity and saturation between materials. Most importantly, the materials were tested on naturally aged acrylic paintings, to see which material(s) are easier to use. The aim of this study was not to find the best retouching material, but rather to validate and enlarge the possibilities for the retouching of acrylic painting.