| When the vascular cannot work normally because of arteries and veins pulse, angioma, thrombus, dilapidation or aging of vascular. Replanting of vascular prosthesis is necessary. Vascular prosthesis is applied widely in such fields as modern vascular, tumor, wound, and reproduction of the organ.Since the vascular prosthesis came into being 40 years ago, there have been quite a few patent and literature on the research of the vascular prosthesis in the world. And in China, there are also a few reports of research on the clinic application. But most of those researches only focus on the manufacture and clinic application, few of which pays attention to the mechanic properties. Up to now, there is no evaluating criterion on the mechanical properties in China. This paper studies mainly the testing of some mechanical properties of the vascular prosthesis in vitro.Comparing with the traditional tensile test instrument of textile. The new testing instrument of longitudinal tensile simulates the conduit condition of the vascular prosthesis in vivo, so it is suitable for the test of longitudinal tensile mechanic properties of vascular prosthesis. By experiment, this paper achieves the comparison between the new testing instrument and old one, and the proof of the rationality of new testing . instrument, later; this paper furthers the explanation of rationality in theory.On the basis of theoretic analysis about the new test instrument of circumferential tensile mechanical properties recommended by ISO, this paper designs an improved testing instrument according to the current material and condition of manufacture, which is expected to prove thefeasibility of it in theory. At the same time of validating the rationality of the new testing instrument.This paper finds that the rupture is tend to occur at the remeshing lines when the vascular prosthesis is endured circumferential traction. Furthermore, this paper studies the mechanical properties of the yarns and fibers in different parts of vascular prostheses, which are in different working procedures, finding that different working procedures, especially the compacting procedure, have different influences greatly on the fibers and yarns. The unhomogeneity of the loop's structure in the remeshing lines was found after the vascular prosthesis has been warp knitted, which is the main reason why. the rupturing position of the prosthesis endured circumferential traction localized preferentially on the remeshing lines. Besides, the properties of fibers carrying at different parts of the vascular prostheses differ greatly. It is predictable that the deterioration of prosthesis, under the physiological loads (periodical pulse blood pressure etc.), could happen firstly in the weaker zone in vivo. The deterioration shortens the life of vascular prosthesis.Through the analysis of testing instrument, which is recommended by ISO, of probe strength of vascular prostheses, this paper tries to propose the improved method to solve the unreasonable press method, and then do some' experiments using the new testing equipment, thus getting the rationality of the new press method.During the design and experiment of the testing instrument of suture retention strength 'of vascular prosthesis, this paper also finds that the detailed methods of samples preparation have not been stated in the testing method of ISO. As a result, errors will appear if we comprehend in normally way. Through observation and analysis, this paper put forward a set of definition for the sample preparation methods, and does experiments on substitute of vascular prostheses to achieve theexperiments on substitute of vascular prostheses to achieve the reasonability of the testing instrument and the sample preparation method.This paper establishes some bio-mechanical property testing instrument to test vascular prostheses' mechanical properties (replace-graft and stent-graft) in vivo, which could provide basis for further research on vascular prostheses. At the same time, on the basis of ana...
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