- A study on highly concentrated lactic acid and the synthesis of lactide from its solution
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Lactic acid is an important platform compound used as raw material for the production of lactide and polylactic acid. However, its concentration and composition distribution are not as simple as those of common compounds. In this work, the mass concentration distribution of highly concentrated lactic acid is determined by back titration. The components of highly concentrated lactic acid, crude lactide, and polymer after the reaction are analyzed by HPLC. Different concentrations of lactic acid solution were prepared for the synthesis of lactide and its content in the product was determined by 1H NMR analysis. We found that lactide is more easily produced from high-concentration lactic acid solution with which the condensed water is easier to release. Hence, the removal of condensed water is crucial to the formation of lactide, although it is not directly formed by esterification of two molecules of lactic acid.
- Liu, Lijuan,Xu, Xiaolong
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p. 856 - 864
(2021/06/16)
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- Furandicarbonyl-polyhydroxy acid ester plasticizer and application thereof
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The invention discloses a furandicarbonyl-polyhydroxy acid ester plasticizer and an application thereof. The furandicarbonyl-polyhydroxy acid ester plasticizer is composed of a furandicarboxylic acidpart, a polyester part formed by oligomerizing hydroxy acid, and a terminal-terminated alcohol part. The plasticizer can be applied to polymer plasticization, and especially shows good compatibility and plasticization efficiency in PVC. Raw materials required by the plasticizer can be derived from biomass, so that the plasticizer has good renewability.
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Paragraph 0023
(2020/04/17)
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- PROCESS FOR THE MANUFACTURE OF LACTIDE
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Process for the manufacture of lactide comprising heating lactic acid in the presence of at least one hygroscopic salt present in an amount of at least 1 mol per mol of lactic acid.
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Page/Page column 9-10
(2012/01/14)
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- PROCESS FOR MANUFACTURING A CYCLIC DIESTER OF AN A-HYDROXY ACID
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Process for manufacturing a cyclic diester of an α-hydroxy acid comprising the following steps: a substantially anhydrous salt of a divalent metal and of an α-hydroxy acid is mixed with a strong acid, the pKa of which is less than that of the α-hydroxy acid and the salt of which with the divalent metal is hygroscopic; andthe mixture is left to react for a sufficient time in order to obtain the cyclic diester dispersed in the hygroscopic salt.
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Page/Page column 4
(2009/12/28)
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- Method and product for skin lightening
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A method and cosmetic product for lightening skin is provided, the method including wiping the skin with a cosmetic towelette. Impregnated on the towelette is an alpha-hydroxy carboxylic acid or salt thereof and a sunscreen agent.
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- Towelette product
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A disposable towelette product is provided which includes a flexible water-insoluble substrate such as a tissue impregnated with an alpha- or beta-hydroxycarboxylic acid in a cosmetically acceptable carrier vehicle. Impregnated cosmetic composition in water will have a pH no higher than 6.8. A silicone microemulsion is present to minimize any stickiness resulting from deposition of the hydroxycarboxylic acid by the towelette onto the skin. In the presence of fatty acid group containing surfactants, the silicone microemulsion controls foul odors that the surfactants may emit through hydrolysis at low pH.
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- Towelette product for minimizing facial fine lines and wrinkles
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A disposable towelette is provided which includes a flexible substrate such as a cellulosic tissue impregnated with an alpha-hydroxycarboxylic add delivered in a cosmetically acceptable carrier vehicle. There is further provided a method for cleansing skin and simultaneously inhibiting fine lines and wrinkles by wiping the skin with the impregnated towelette.
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- SHORT CHAIN 2-HYDROXYCARBOXYLIC ACID-BASED DERIVATIVES OF CERAMIDES
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The present invention relates to active ceramide derivatives. Specifically, the invention relates to 2(alpha)-hydroxycarboxylic acid-based ceramide derivatives. The present invention describes a method for obtaining these compounds. The invention also relates to the use of these compounds in cosmetic compositions.
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- Compositions and methods for enhancing the topical effects of sunscreen agents
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Uses of topical compositions comprising a 2-hydroxycarboxylic acid or related compound to alleviate or improve signs of skin, nail and hair changes associated with intrinsic or extrinsic aging are disclosed. 2-Hydroxycarboxylic acids and their related compounds include, for example, 2-hydroxyethanoic acid, 2-hydroxypropanoic acid, 2-methyl 2-hydroxypropanoic acid, 2-phenyl 2-hydroxyethanoic acid, 2-phenyl 2-methyl 2-hydroxyethanoic acid, 2-phenyl 3-hydroxypropanoic acid, 2,2-diphenyl 2-hydroxyethanoic acid, 2-hydroxybutane-1,4-dioicacid, 2,3-hihydroxybutane-1,4-dioic acid, 2-carboxy 2-hydroxypentane-1,5-dioic acid, 2-ketopropanoic acid, methyl 2-ketopropanoate, ethyl 2-ketopropanoate, and gluconolactone. Topical application of compositions comprising 2-hydroxycarboxylic acid and/or related compounds has been found to alleviate or improve skin lines; blotches; blemishes; nodules; wrinkles; pigmented spots; atrophy; precancerous lesions; elastotic changes characterized by leathery, coarse, rough, dry and yellowish skin; and other skin changes associated with intrinsic aging or skin damages caused by extrinsic factors such as sunlight, radiations, air pollution, wind, cold, dampness, heat, chemicals, smoke and cigarette smoking. Topical applications of such compositions have also been found to improve the overall qualities of nail and hair affected by intrinsic aging or damaged by extrinsic factors.
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