| 학회 | 한국고분자학회 |
| 학술대회 | 2005년 가을 (10/13 ~ 10/14, 제주 ICC) |
| 권호 | 30권 2호 |
| 발표분야 | 의료용 고분자 부문위원회 |
| 제목 | Surface modification of hydroxyapatite nano-crystals by grafting polymers containing phosphonic acid groups |
| 초록 | Surface modification of hydroxyapatite (HAp) nano-crystals with polymers has attracted expanding interests since it can produce the HAp with enhanced colloidal stability in solutions. Besides, when modified HAp is used to make HAp/polymer nano-composites, the interfacial adhesion can be greatly enhanced. In this study, we aimed to develop a novel modification method of HAp nano-crystals by surface grafting polymerization of vinyl phosphonic acid (VPA). Grafting reaction of VPA on hydrothermally synthesized HAp nano-crystals was carried using an equimolar mixture of potassium persulfate and sodium metabisulfite as redox initiating system in an aqueous media. The surface grafting poly(vinyl phosphonic acid) (PVPA) on HAp nano-crystals was evidenced by Fourier transformation infrared (FT-IR) spectroscopy and X-ray powder diffraction The percent grafting (wt%) estimated by thermal gravimetric analysis was in the range of 5～20 wt%. Inductively couple plasma mass spectroscopy (ICP MS) showed that the Ca/P molar ratio decreased from 1.67 to 1.36 with increasing the feed VPA amount. TEM measurements and time-dependent phase monitoring indicated that the colloidal stability M-HAp over unmodified HAp in water dramatically increased, and modified HAp tended to exist as single nano-crystals without aggregation in an aqueous phase. The data in this study indicated that the grafted phosphonic acid groups can offer HAp with numerous advantages such as good dispersion in the polymer matrix and strong adhesion with cationic biopolymers including chitosan. Besides, phosphonic acid groups on HAp nano-surfaces can generate the nano-composites with the favorable environment for cell attachment and proliferation as well as osteoconduction induced by biomineralization. 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; Phosphonic acid; Surface modification; Grafting |
