Vascular grafts are special tubes that serve as artificial replacements for damaged blood vessels.They are already commercially available, mainly produced from Polyethylene Terephthalate(PET) knitted or woven fabrics or the expanded polytetrafluoroethylene(ePTFE).The purpose ofthe vascular graft prostheses or implantation is not only to keep a patient alive, but also for thepatient to continue with their normal lives, as a worker.PET and ePTFE have been successfullyused in large diameter grafts;however, small caliber grafts still show an unacceptable highpercentage of failure, due to surface forces, blood plasma proteins are adsorbed by the graft,resulting in inflammation, infection, thrombus formation and ultimately vessel reclose.Poly (ε-caprolactone) (PCL) is a promising biodegradable polymer with a longer degradation time.Themechanical properties of the pure PCL cannot meet up with the requirement of vascular grafts.In this thesis composite materials of PCL/PET consider as a novel biomedical materials which itmay use to prepare vascular graft with less defects, as composite materials form more than layer,to imitation the human blood vessel which composed of three layers.One of these layers tocontribute in the increases of mechanical properties (PET), while the others to improve thebiological properties (PCL), which leads to decrease the surface forces of PET and improve themechanical properties of the PCL.
　　 The aims of this study are to prepare a new prototype small diameter vascular graft from PCL reinforced with PETweft-knitted tube fabric.Study the influence of the materials parameters and textile structure on the properties.Investigate the relationship between structure and elastic properties.
　　 Generally, PET weft knitting tube fabrics (6mm diameter) were fabricated with different loopdensity using small single jersey weft knitting machine.Acetic has been used to dissolve PCL(three molecular weight were used) under stirring at room temperature until a homogeneoussolution was formed.PCL solution was composited outside and inside of the weft-knitting fabricwith a PTFE rod, and the pure PCL tube was taken as a control.The samples were dried byfreeze drying method.
　　 The samples have been characterized by using: scanning electron microscopy to determent theporosity structure, textiles universal strength tester has been used to determent the tensilestrength and the suture retention strength.The water permeability device has been used todeterment the water permeability through the wall graft, filament mightiness instrument to testthe elastic recovery and the dynamic-simulated system to determent the compliance.
　　 The new prototype vascular grafts have been shown good porosity.And the tensile properties,elastic recovery and the suture retention strength of the new vascular grafts were improvedcompared with pure PCL vascular graft.However, a significant difference in compliance hasshown between the samples, which was produced and the healthy host arteries.On the otherhand, with the increase the molecular weight of the PCL, the pore size and the elastic recoveryhave been improved.Also when increase the loop density of the fabric, the elastic recovery andthe suture retention strength have shown improvement.
　　 The new composite prototype vascular grafts are promising and they have good potentialapplications in clinic, due to the good mechanical and biological properties.