We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
微型支架多向拉伸构建及其支撑力学检测.
- Authors
韩本松; 薛锋; 莫秀梅
- Abstract
BACKGROUND: Polylactic acid is a kind of biodegradable macromolecule material with good properties,which is widely used in cardiovascular stents, and internal fixation nail-plate. By stretching amorphous polylactic acid, chain orientation and crystalline structure can be obtained, and its mechanical properties are improved.OBJECTIVE: To investigate the feasibility of multi-directional stretching for the preparation of polylactic acid micro-stents.METHODS: The ring-shaped stent base rod was made by polylactic acid with a molecular weight of 100 kDa.The multi-directional hot stretching was carried out in a self-made drafter. The draw ratio was 0, 0.5, 1, 1.5, 2,and 2.5, respectively. After the stents were stretched and formed, the radical strength was detected by tension method and the longitudinal section of base rod of the stent was observed by scanning electron microscope.RESULTS AND CONCLUSION:(1) Two micro-frames with diameters of 0.5 mm(group A) and 1 mm(group B)were prepared. The diameter of the base rod was 0.08-0.1 mm, and the length was 6 mm.(2) Stretching process could significantly improve the radial support performance of polylactic acid micro-stent, the radial support force increased with the increase of the draw ratio, which reached the maximum at a draw ratio of 2, then the support force decreased.(3) Scanning electron microscope showed that when the stretching ratio was 0, and 0.5, the internal unit structure of the base rod arranged more tightly and regularly, and gradually arranged along the axial direction of the base rod; when the stretching ratio was 1, the structural unit exhibited a lateral bending orientation, but wrinkles were uneven. When the stretching ratio was 1.5 and 2, the bending orientation was further enhanced, and the compact structure was restored under the new structure arrangement. When the stretching ratio was 2.5, the structural unit was rough and the microstructure was unevenly broken.(4) These results suggest that micro-stent can be formed by multi-directional stretch, and the stretching ratio can obviously affect the stent performance. The orientation of the stent is obviously improved. The higher the stretching ratio, the stronger the radial support force, and the more reliable support strength of small vessel repair.
- Publication
Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu, 2019, Vol 23, Issue 26, p4225
- ISSN
2095-4344
- Publication type
Article
- DOI
10.3969/j.issn.2095-4344.1364