摘要:
The present invention relates to esters of diacids and cellulosic materials and methods for making thereof. The ester has the chemical composition of Formula (I) Formula I where R1, R2, and R3 can be the same or different, and each of which is selected from —H, —COR′, —R′″, or —COR″ COOH, with the proviso that at least one of the R1, R2, or R3 is —COR″ COOH; R′ is an alkyl, alkenyl, alkynyl, or aromatic group; R″ is an alkyl, alkenyl, or alkynyl group having 4 or more carbon atoms (≧C4); and R′″ is an alkyl, alkenyl, alkynyl, polyol, or aromatic group.
摘要:
Water soluble or water-dispersible cellulose acetoacetate esters are prepared by contacting a cellulose material with diketene, an alkyl acetoacetate, 2,2,6-trimethyl-4H-1,3-dioxin-4-one or a mixture thereof and a carboxylic anhydride in a solvent system comprising lithium chloride plus a carboxamide. Compositions containing the cellulose acetoacetate esters are useful for coatings applications.
摘要:
A method of iodinating hydroxyaromatic and aminoaromatic compounds is disclosed, comprising reacting the hydroxyaromatic or aminoaromatic compound with an aqueous solution of a metal iodide and a metal hypochlorite at a temperature about -100.degree. to 100.degree. C. in the presence of an alcohol having 1-10 carbon atoms.
摘要:
A process for the production of aromatic carboxylic acids which comprises carbonylating substituted iodoaromatic compounds in the presence of carbon monoxide, a catalytic amount of a transition metal catalyst, and a Bronsted base in a mixture of a carboxylic acid and water under aromatic carboxylic acid forming conditions of temperature and pressure.
摘要:
Methods for the cross-metathesis of polysaccharides with one or more olefin-terminated side chains and cross-metathesized products are described. In an exemplary embodiment, a method for the synthesis of cellulose co-carboxyesters via olefin cross-metathesis is described. Conditions of the reactions were relatively mild and the olefin-substituted polysaccharides and the appropriate monomeric olefin partners appear to follow Grubbs rules as summarized herein. The compounds and methods may be useful for structure-property studies, particularly those aimed at developing polymers for drug delivery, such as for controlled-release drug delivery systems, controlled-release coatings, increasing bioavailability of drugs, and maintaining drug supersaturation in the GI tract.
摘要:
The present invention relates to a process for preparing cellulose esters having a total DS/AGU of 0.1 to 3.0, said process comprising contacting the following: (i) a cellulose material, (ii) a solubilizing amount of a solvent system comprising a carboxamide diluent or a urea-based diluent, (iii) an acylating reagent, and (iv) a titanium-containing compound.
摘要:
Process for reducing the degree of substitution of cellulose esters employing carboxylic acids as solvolysis promoters is disclosed. Exemplary cellulose esters are cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, and cellulose acetate butyrate.
摘要:
Process for reducing the degree of substitution of cellulose esters employing Lewis acids as solvolysis promoters is disclosed. Novel low degree of substitution cellulose esters produced by the invention process are also described.
摘要:
Disclosed is a process for the preparation of 2,4,6-trichlorophenylhydrazine by chlorinating the reaction product of phenylhydrazine and a dicarboxylic anhydride to obtain an N-(2,4,6-trichloroanilino)dicarboximide which is reacted with a base capable of liberating 2,4,6-trichlorophenylhydrazine therefrom.
摘要:
Methods for the cross-metathesis of polysaccharides with one or more olefin-terminated side chains and cross-metathesized products are described. In an exemplary embodiment, a method for the synthesis of cellulose ω-carboxyesters via olefin cross-metathesis with acrylates is described. Conditions of the reactions were relatively mild and the olefin-substituted polysaccharides and the appropriate acrylate partners appear to follow Grubbs rules as summarized herein. Additionally, a method of hydrogenation of the cross-metathesized product is described. The compounds and methods may be useful for waterborne coating applications, adhesives, lubricants, or any product in need of dispersion in an aqueous media.