Abstract: An apparatus for carboxylating wood pulp which utilizes the wood pulp bleach plant and the method of carboxylating the pulp which takes place in the bleach plant.

Abstract: An apparatus for carboxylating wood pulp which utilizes the wood pulp bleach plant and the method of carboxylating the pulp which takes place in the bleach plant.

Abstract: A method of making a carboxylated carbohydrate is disclosed, cellulose being a preferred carbohydrate material. Carboxylated cellulose fibers can be produced whose fiber strength and degree of polymerization is not significantly sacrificed. The method involves the use of a catalytic amount of a hindered cyclic oxammonium compounds as a primary oxidant and chlorine dioxide as a secondary oxidant in an aqueous environment. The oxammonium compounds may be formed in situ from their corresponding amine, hydroxylamine, or nitroxyl compounds. The oxidized cellulose may be stabilized against D.P. loss and color reversion by further treatment with an oxidant such as sodium chlorite or a chlorine dioxide/hydrogen peroxide mixture. Alternatively it may be treated with a reducing agent such as sodium borohydride. In the case of cellulose the method results in a high percentage of carboxyl groups located at the fiber surface.

Abstract: A process for microencapsulating bioactive substances in biocompatible polymers according to the phase-separation principle, wherein an excess of an ethyl or isopropyl ester of a straight-chain fatty acid having 12-18 carbon atoms is used as the hardening liquid, and the pharmaceutical compositions containing the microcapsules prepared by this process. Isopropyl myristate and isopropyl palmitate are preferred hardening liquids.