| 학회 | 한국고분자학회 |
| 학술대회 | 2005년 가을 (10/13 ~ 10/14, 제주 ICC) |
| 권호 | 30권 2호 |
| 발표분야 | 의료용 고분자 부문위원회 |
| 제목 | Grafting polymerization of ε-caprolactone on the surface of hydroxyapatite nano-crystals |
| 초록 | The composites of HAp and biodegradable polymers have been widely studied as scaffolds for bone regeneration and bone-related drug delivery systems due to the combined osteoinductivity and biodegradability. The interfacial adhesion between HAp and the polymers is a critical factor to determine the mechanical properties of the composites. Thus, a need exist to provide systematic approach for enhancing interfacial adhesion strength between HAp and the polymers. The aim in this study is to develop a novel method of surface modification of hydroxyapatite (HAp) nano-crystals by surface grafting polymerization of ε-caprolactone (CL). Our research has been performed on an assumption that the grafted PCL onto HAp (C-HAp) may play a important role to improve the affinity with the PCL polymer phase. Grafting polymerization of CL was carried out by the surface hydroxyl groups of HAp as initiating sites, and, for introducing more reactive hydroxyl groups, HAp surface-modified with 2-hydroxypropanoic acid (L-lactic acid) was also used. TGA experiments showed that nano-surface of modified HAp (L-HAp) acted as more favorable site for PCL grafting than that of unmodified HAp, and the degree of grafting (wt%) was higher than using ungrafted HAp. The suface grafting was proved by FT-IR, and XRD measurements indicated that the surface modification reaction of HAp did not induce any phase transformation of the HAp crystalline structure. TEM measurements and time-dependent phase monitoring indicated that the colloidal stability C-HAp and LC-HAp over unmodified HAp in organic solvents, such as chloroform, methylene chloride, and THF, became pronounced markedly, and modified HAp tended to exist as single nano-crystals without aggregation in solutions. These results indicated that nano-surface modified HAp can act a significant role in making hybrid materials useful for bone-related applications with enhanced mechanical properties and homogeneous bulk properties. Acknowledgement. This research was supported by a grant (code #: 05K1501-01510) from 'Center for Nanostructured Materials Technology' under '21st Century Frontier R&D Programs' of the Ministry of Science and Technology, Korea |
| 저자 | 최형우, 이상천, 김경자 |
| 소속 | 요업(세라믹)기술원 생체재료팀 |
| 키워드 | Hydroxyapatite; ε-Caprolactone; Surface modification; Grafting |
