RESUMO
To provide self-healing epoxy composite with adequate heat resistance for high-performance application, we developed a novel microencapsulated epoxy/mercaptan healing agent. The key measure lies in usage of diglycidyl ether of bisphenol A (EPON 828) as the polymerizable component and 2,4,6-tris(dimethylaminomethyl)phenol (DMP-30) as the catalyst. Because of the higher thermal stability of EPON 828 and lower volatility of DMP-30, the healing agent and the self-healing composite not only survive high-temperature curing and thermal exposure, but also offer satisfactory capability of autonomous properties restoration, as characterized by both fracture mechanics and fatigue tests. Especially when the operation temperature is not higher than 200 °C, the performance of the healing system is nearly independent of thermal history.
RESUMO
OBJECTIVE: To evaluate the clinical results of anterior spinal release combined with posterior correction for the treatment of severe scoliosis. METHODS: Twenty-three patients of severe scoliosis were retrospectively analyzed from July 2000 to January 2007. There were 12 males and 11 females with an average age of 15.3 years (ranging from 9 to 18 years). Including 9 congenital scoliosis, 13 idiopethic scoliosis and 1 neurofibromatosis scoliosis. The pre-operative coronal Cobb angles of scoliosis were from 810 to 1260 with the mean of 97.4 degrees. RESULTS: The post-operative coronal Cobb angles was for 100-450 (37.4 degrees on average). All patients were followed up for 6-24 months (means 10 months). Two cases occurrenced addition phenomemon in junctional zone. There were no hook displacement and rod breaking at follow-up. CONCLUSION: Anterior relaxation and posterior correction is a safe and effective treatment. It can achieve well clinical results for the treatment of severe scoliosis.