| abstract |
This invention relates to novel carboxymethyl-etherified starch derivatives and its manufacturing method and more particularly, to the novel carboxymethyl-etherified starch derivatives and its manufacturing method, wherein its viscosity in 5 % aqueous solution is 15≈600 cps, when measured by a viscometer in Hakke rotary type; permeability in 0.1 % aqueous solution shows more than 95 % in 625 nm, when measured by UV spectrophotometer; viscosity values at the maximum temperature of 95 °C and at the temperature cooled to 50 °C are 6≈304 BU and 6≈720 BU, respectively when measured by Brabender viscometer. According to this invention, the cool water-soluble carboxymethyl-etherified starch derivatives are prepared in the following steps: starches (such as corn, potato, wheat and rice) as main materials are dissolved in organic solvents such as lower alcohol without hydrolysis, or hydrolyzed in the presence of inorganic acids such as hydrochloric acid or sulfuric acid at 25 to 75 °C for 30 minutes to 72 hours. Then, with the addition of etherifing agent in the presence of alkali, some organic solvent of lower alcohol was further added to the mixture for reaction thereof. The reactant was neutralized, purified with organic solvents and dried to give the desired product. |