Chitosan Graft Copolymerization Of Pharmaceutical Applications Of New Methods And Products

In this thesis, using chitosan as trunk polymer, and acrylamide(AM) and methyl methacrylate(MMA) as grafting monomer, graft copolymers were composed byγ-ray irradiation and composite initiation system(cerium ammonium nitrate-potassium persulfate-sodium bisulfate, ammonium persulfate-sodium thiosulfate). The first system to trigger graft explored. The radiation conditions, the reaction temperature, reaction time, monomer-to-chitosan ratio, and the effect of different additives on the grafting parameters like grafting rate (G) and grafting efficiency (GE) were investigated. To find the optimal graft conditions and compare their respective advantages and disadvantages. The structure of graft copolymers was characterized by means of infrared spectroscopy and (IR) and thermal analysis(DSC). A drug delivery and performance graft product was studied, and applied to the study of Chinese medicine flocculation. The results was showed:1. By the research of chitosan and AM grafting copolymerization, influencing rules of reaction conditions to graft reaction were discussed. Chitosan and AM in cerium ammonium nitrate-potassium persulfate-sodium bisulfite initiator, under the optimal conditions: full of N₂, the reaction time 3.5h, the reaction temperature 40℃, AM: chitosan 7:1, initiator concentration 1.25 mmol·L^-1(cerium ammonium nitrate: potassium persulfate-sodium bisulfate=1:1). In Co⁶⁰γ, ray initiator, under the optimal conditions: radiation dosages 200Gy, dosages rate 1.6 Gy·min^-1, AM: chitosan 6:1, chitosan concentration 2%.2. By the research of chitosan and MMA grafting copolymerization, influencing rules of reaction conditions to graft reaction were discussed. Chitosan and MMA optimal reaction conditions were as follows: full of N₂, the reaction temperature 70℃, the reaction time 5.5 h, MMA 4 ml, ammonium persulfate concentration 3.5 mmol·L^-1, sodium thiosulfate concentration 2.5 mmol·L^-1. In Co⁶⁰γ, ray initiator, under the optimal conditions: 40ml fixed chitosan solution, radiation dosages 1000 Gy, MMA 2ml, chitosan concentration 2%.3. By comparison initiation system: the G and GE of composite initiation system were higher than theγ-ray irradiation and the single initiator, however, because ofγ-ray irradiation no catalyst, no produce pollution, simple post-treatment, and reducing costs, moreover, due toγ-firing-penetrating power, the grafting reaction triggered by the formation of active sites and in the entire system more evenly distributed. Thus, no matter whether it is caused composite or irradiation with Co⁶⁰γ, ray induced graft polymerization reactions in the application are equally important.4. By infrared spectroscopy and thermal analysis confirmed in the molecular chain of chitosan indeed exist AM and MMA.5. Chitosan graft product as a drug delivery system of berberine, a equality release rate in the simulation of artificial gastric juice can be maintained within 0～200min, graft copolymers of chitosan-MMA can be used as a drug delivery system.6. Graft copolymer was applied to the study of Chinese medicine flocculation process. The different viscosities graft product dosage, pH, temperature, the compound flocculant and compared with chitosan as a flocculant to the effects of flocculation were investigated. The results showed: special sticky solution(concentration 10mg·ml^-1)dosage 4ml, pH 4.0, temperature 40℃, 3ml compound dosage of the strongest adsorption capacity and the largest transmission. In comparison with the effect of chitosan flocculation, showed good character.