Synthesis of (meth) acrylic anhydride by transanhydrization

    公开(公告)号:US09969670B2

    公开(公告)日:2018-05-15

    申请号:US15111258

    申请日:2015-01-20

    CPC classification number: C07C51/573 C07C51/56 C07C57/04

    Abstract: The invention relates to a method for producing a (meth)acrylic anhydride A-C(═O)—O—(O═)C-A, comprising the following steps: a) a step of reacting an anhydride B—C(═O)—O—(O═)C—B with an acid A-COOH, resulting in the formation of mixed anhydride A-C(═O)—O—(O═)C—B and acid B—COOH; and b) a step of reacting the mixed anhydride with A-COOH, resulting in the (meth)acrylic anhydride. According to the invention, reaction steps (a) and (b) are carried out in the presence of hydrated triflic acid, and the anhydride A-C(═O)—O—(O═)C-A is isolated from the reaction medium produced in step (b) as follows: e1) heavy compounds having a volatility less than or equal to that of the anhydride A-C(═O)—O—(O═)C-A are separated from the reaction medium, said compounds including the anhydride and the hydrated triflic acid; e2) the anhydride is separated from the heavy compounds by difference in volatility.

    Biopolymer-based seed coatings compositions and methods for use

    公开(公告)号:US11284558B2

    公开(公告)日:2022-03-29

    申请号:US16192952

    申请日:2018-11-16

    Abstract: A seed or seedling is coated with a cross-linked biopolymer and, optionally, a second binder selected from underivatized guar, cationic hydroxypropyl guar, polyacrylamide, poly(methacrylic acid), poly(acrylic acid), polyacrylate, poly(ethylene glycol), polyethyleneoxide, polyamide, hydroxypropyl guar, carboxymethyl guar, carboxymethylhydroxypropyl guar, underivatized starch, cationic starch, corn starch, wheat starch, rice starch, potato starch, tapioca, waxy maize, sorghum, waxy sarghum, sago, dextrin, chitin, chitosan, xanthan gum, carageenan gum, gum karaya, gum arabic, pectin, cellulose, hydroxycellulose, hydroxyalkyl cellulose, hydroxyethyl cellulose, carboxymethylhydroxyethyl cellulose, or hydroxypropyl cellulose. The seed coating composition is characterized by a dust value, as measured using a Heubach dustmeter device, which is lower by at least 30% as compared to an analogous composition that does not contain the crosslinked biopolymer.

Patent Agency Ranking