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In this thesis, the solvent evaporation method and immersion - dry molding prepared the biodegradable catheter can be used for the repair of peripheral nerve injury . This topic selected Chitosan (CS) and polycaprolactone (PCL) an organic polymer material as a base material prepared nerve conduit , respectively, the chitosan and poly ( caprolactone ) with different weight ratios , stainless steel wire as the central axis of the preparation was a long 2 cm, a diameter of 2 mm and a wall thickness of 0.5 mm stent catheter . Polycaprolactone in slow degradation in vivo , cells are not easily adsorbed and other shortcomings , but excellent in its mechanical properties and plasticity ; rapid chitosan in vivo degradation , containing a large number of positively charged -NH3 group to facilitate cell adherent, but its presence in the swollen state brittle fracture strain is poor and other shortcomings , the experiments chitosan with polycaprolactone blend in order to achieve a complementary performance . The impact factors of the two materials blend performance into a gel performance and preparation process , the system the catheter of got five different quality than the mixed (chitosan , CS-75/PCL-25 , CS- 50 / PCL-50, CS-25/PCL-75, PCL). And conducted vitro degradation experiments explore . By measuring the degradation of the pH of the medium change , the change in mass of the composite catheter understanding catheter degradation rate with nerve regeneration speed matches . By stretching the swelling properties of the catheter , the resistance to compression and other mechanical properties , and further optimize the structure and composition of the catheter component ratio . Drawn: at room temperature , chitosan molecular weight of 500 ~ 600 KDa, polycaprolactone molecular weight of 5 × 104 to 8 × 104 , and the acetic acid as a common solvent , dissolving the two materials , respectively obtained with different concentrations of polycaprolactone lactone solution and chitosan solution , blending solvent concentration in more than 75% can be homogeneous , clear solution . Chitosan and polycaprolactone mass ratio of 1:1, and the wall thickness was prepared for the best performance of a 0.5 mm conduit .
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