New Production Technology Of Chitosan And Carboxymethyl Chitosan

Existing technology is the way of extracting chitosan that decalcified by acid, take off the protein by dilute alkali, then deacetylation of chitin obtained by concentrated alkali. It exists disadvantages about big consumption of acid and alkali, long processing time, more isolated and purified process, produce a large number of high concentrations of acidic and alkaline waste water containing salt, failed to achieve full development and high value-added utilization for the shell of crustaceans such as shrimp and crab. So not only have high price of production, but also lead to the degradation of chitin that caused by acidic conditions, and waste precious resources of biological calcium and protein, seriously pollute the environment. So developed high quality, low price and green environmental production processe about chitin and its derivatives is extremely valuable.The paper took a new technology that do not use acid to decalcifiied for preserving calcium carbonate of the raw material, invented quick, easy and extensive production processe of chitosan/calcium carbonate mixture, carboxymethyl chitosan/calcium carbonate mixture with the shell of crustaceans such as shrimp and crab as raw material by "one-pot", in mixed system about isopropanol-sodium hydroxide-E₂O, under the condition of moderate and low alkaline, At the same time isolated by-product of amino acids and small peptides, The resources of crustaceans can realize full development and high value-added utilization. It determined the optimum conditions, and passed the test card, we can get a range of products. The tensile strength, broken degree, folding strength, tear strength and bonding strength of paper have increased by about10%to50%when added carboxymethyl chitosan, it is an excellent paper strength additive. The mixture of carboxymethyl chitosan and biological CaCO₃makes the resin tensile shear strength of the board can reach1.6MPa, And the bond strength is large when complex with the natural organic adhesive, due to the formation of cross-linked, interpenetrating network structure, can significantly improve the bonding properties and preserve calcium carbonate that is the natural honeycomb structure, it can improve adhesion for more dense membrane structure, so can be developed as a new generation of cost-effective, outstanding, natural, environmental adhesion agent.