摘要:
The present invention provides amidic polymers, which exhibit shale swelling inhibitor activity having improved biodegradability. The amidic polymers of the invention may be employed in a wide variety of compositions, particularly in subterranean drilling operations. Non-limiting generic structures of the amidic polymers are set out below: formula (1) wherein R1-R3 and integers m and n are defined herein.
摘要:
A method for manufacturing a modified hydroxyethyl starch carrying a heptonic acid residue on at least one of its termini is disclosed. Within this method, the following steps are carried out: a) dissolving hydroxyethyl starch in water, b) adjusting the pH value to a value of 8.0 to 10.0, c) adding a cyanide compound to the hydroxyethyl starch solution, heating the solution to a temperature of 80 to 99° C. and keeping it at this temperature for a first time period, and d) adjusting the pH value to a value of 2.0 to 4.0, bringing the solution to a temperature of 50 to 90° C. and keeping it at this temperature for a second time period.
摘要:
The present disclosure relates to particles comprising carboxyalkyl starch that are permeated with an acidic gas and their uses as absorbent materials. It was discovered that superabsorbent materials could be obtained from carboxyalkyl starch particles permeated with the acidic gas and heated to a temperature of at least 100° C. until they reach an AUL at 0.7 psi. of at least 14 g/g and a CRC of at least 18 g/g. Moreover, it was discovered that the pH of alkaline starch extrudates can be adjusted by permeating particles of the extrudate with the acidic gas even with treating the particles to temperatures less than 100° C. The carboxyalkyl starch particles obtained by the methods described herein are characterized as having intramolecular ester bonds, which are greater in number at the surface of the particle than in the core, and the particles have a greater concentration of cation of the acidic gas at the surface than a the core.
摘要:
The present disclosure relates to particles comprising carboxyalkyl starch that are permeated with an acidic gas and their uses as absorbent materials. It was discovered that superabsorbent materials could be obtained from carboxyalkyl starch particles permeated with the acidic gas and heated to a temperature of at least 100° C. until they reach an AUL at 0.7 psi. of at least 14 g/g and a CRC of at least 18 g/g. Moreover, it was discovered that the pH of alkaline starch extrudates can be adjusted by permeating particles of the extrudate with the acidic gas even with treating the particles to temperatures less than 100° C. The carboxyalkyl starch particles obtained by the methods described herein are characterized as having intramolecular ester bonds, which are greater in number at the surface of the particle than in the core, and the particles have a greater concentration of cation of the acidic gas at the surface than a the core.
摘要:
According to the invention, a hydrogel comprising chemically modified polysaccharides and proteins is provided. Furthermore, a method is provided in order to produce a hydrogel from mixtures of polysaccharides and proteins. According to the invention, the polysaccharides and proteins are modified chemically covalently and crosslinked chemically intermolecularly by the method. The chemically derivatised polysaccharide-protein blend (abbreviated to “PPB”) which is produced according to the invention is characterised in that it forms a hydrogel in an aqueous medium. The PPB hydrogel according to the invention is characterised by a high water-binding potential and a high adhesive effect. For example in building chemistry, the PPB hydrogel according to the invention has an advantageous effect on the adhesion- and slippage behaviour of tiles.
摘要:
A modified starch material for biocompatible hemostasis, biocompatible adhesion prevention, tissue healing promotion, absorbable surgical wound sealing and tissue bonding, when applied as a biocompatible modified starch to the tissue of animals. The modified starch material produces hemostasis, reduces bleeding of the wound, extravasation of blood and tissue exudation, preserves the wound surface or the wound in relative wetness or dryness, inhibits the growth of bacteria and inflammatory response, minimizes tissue inflammation, and relieves patient pain. Any excess modified starch not involved in hemostatic activity is readily dissolved and rinsed away through saline irrigation during operation. After treatment of surgical wounds, combat wounds, trauma and emergency wounds, the modified starch hemostatic material is rapidly absorbed by the body without the complications associated with gauze and bandage removal.
摘要:
The present invention relates to hydroxyalkyl starch conjugates, a method for preparing the same, the hydroxyalkyl starch conjugate comprising a hydroxyalkyl starch derivative and a cytotoxic agent and the cytotoxic agent comprising at least one tertiary hydroxyl group, wherein the hydroxyalkyl starch is linked via said tertiary hydroxyl group to the cytotoxic agent. The conjugates according to the present invention have a structure according to the following formula HAS′(-L-M)n wherein M is a residue of the cytotoxic agent, L is a linking moiety, HAS′ is the residue of the hydroxyalkyl starch derivative, and n is greater than or equal to 1, and wherein the hydroxyalkyl starch derivative has a mean molecular weight (MW) above the renal threshold.
摘要:
A reactive extrusion process for the production of substituted polysaccharides, in particular, cellulose acetate, starch acetate, carboxymethyl cellulose, and carboxymethyl starch.
摘要:
A powder of cold-soluble polysaccharide and polyol, which is highly viscous in water and suitable for direct compression, and a method for preparing the powder and uses thereof are described, the powder being notably intended for preparing solid forms with controlled release of an active principle.
摘要:
The present invention relates to a method for preparing hydroxyalkyl starch. The method for preparing hydroxyalkyl starch comprises the steps of hydrolyzing starch, reducing the hydrolyzed starch, and substituting the reduced starch with hydroxyalkyl group in a dry process.