| 摘要 |
A method for fabricating human tissue prosthesis. The method produces a prosthesis that has mechanical compliance properties similar to that of body tissue. The prosthesis fabrication method utilizes, for example, a polyurethane urea-linked block copolymer system which in the cured state is a thermoset elastomer which has lumen surface qualities which are essentially optically flat. The formulation is essentially a single a single step process. A clean mandrel is horizontally clasped in the jaws of a variable speed motor and slowly rotated. The pre-polymer solution is placed on the rotating mandrel and thickness adjusted by a mechanical wiper. The rotating mandrel having pre-polymer of desired thickness is placed in a sub-atmospheric environment to remove dissolved gasses and permitted to initially cure while rotating. The final cure is achieved in a sub-atmospheric environment. Removal of the cured polymeric prosthesis from the mandrel is achieved by placing same in an aqueous solution at a temperature less than final cure temperature and then slipping the prosthesis from the mandrel. The combination of polymer system formulations and fabrication techniques has led to the development of vascular grafts which are non-thrombogenic, non-hemolytic, and which have a compliance factor closely matching its correspondent physiologic counterpart. |
