均匀共沉淀-水热法制备纤维状羟基磷酸钙/壳聚糖复合粉体

Preparition of a Fibrous Hydroxypatite/Chitosan Composited Powder with Homogeneous Co-precipitation-hydrothermal Method

以尿素为沉淀剂,运用溶液均匀共沉淀法制得纤维状羟基磷灰石(HAP)和无定形颗粒状壳聚糖(CS)的复合粉体,通过水热处理调整纤维状HAP晶粒尺寸的大小,对粉体进行了 XRD、TEM、IR及化学组成(Ca/P)表征.均匀共沉淀过程中,pH值对粉体Ca/P有很大影响, pH =8.0 和 6.1,复合粉体 Ca/P 分别为 1.65(理论值为1.67)和1.48;粉体无机晶相主要由HAP和一定磷酸氢钙 (DCPA)构成,DCPA相对含量随 pH的不同发生变化.水热(0.2 MPa)处理后,粉体XRD结果表明,纤维状 HAP晶粒尺寸减小,晶相和 Ca/P有一定的变化,其变化也与水热处理前溶液的 pH有关.粉体TEM显示, pH=8.1条件下,水热处理后(前),纤维状HAP直径60 nm^300 nm(150 nm^1μm),长度0.5μm^2μm(2μm^4μm).复合粉体与物理混合粉体红外光谱(IR)相比,在 1 654 cm-1and 1 560 cm-1处有新波峰出现.

Using urea as the precipitant,the fibrous hydroxypatite(HAP)/chitosan(CS)composited powders were prepared with homogeneous co-precipitation, and the grain size of HAP was adjusted with hydrothermal treating(0.2 MPa). The composited powders were characterised by XRD,TEM, IR and chemical composition(Ca/P). In the course of homogeneous co-precipitating, the pH value had great influence on Ca/P of the composited powders. At pH=8.0 and 6.1, the values of powders' Ca/P was 1.65(theoratic value 1.67) and 1.48 respectively. The inorganic phases of the powders were mainly composed of HAP and definite Calcium Hydrogen Phosphate( DCPA )which changed with the final pH of co-precipitating process . After hydrothermal treating, the XRD results indicated grain size of HAP was decreased. Ca/P and the composition of the powders' crystal phase had some certain changes related with the pH before hydrothermal treating. At pH=8.1 , TEM showed fibrous HAP's diameter range of post-(pre-)hydrothermal was 60 nm～300 nm(150 nm～1 μm),and length range was 0.5 μm～2 μm (2 μm^4 μm). Compared with mechanical mixed HAP/CS powders, the composited powders had new wave peaks at 1 654 cm~(-1_ and 1 560 cm~(-1_ of the IR curve .