尿素共沉淀法制备纤维状羟基磷灰石/壳聚糖复合粉料

Preparation of a Fibrous Hydroxyapatite(HAP)/Chitosan Composite Powder by Urea Coprecipitation

以尿素为沉淀剂,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,对粉体进行了XRD、SEM、IR表征。粉体无机相的Ca/P及晶相组成可以在共沉淀过程中,通过改变尿素浓度调节体系pH值而控制。尿素浓度为10mol/L,体系pH=72,复合粉体无机相的Ca与P摩尔比为164时,无机相基本为羟基磷灰石;尿素浓度05mol/L,体系pH=61,复合粉体无机相的Ca与P摩尔比为142时,无机相含有部分磷酸氢钙(DCPA)。复合粉体中羟基磷灰石的平均长度为40μm,平均直径为600nm,均匀分布在壳聚糖颗粒中。与物理混合的HAP/CS相比,共沉淀法得到的粉体在红外光谱1654和1560cm-1处有新峰出现。

The composite powder of fibrous hydroxyapatite(HAP)/amorphous chitosan(CS) was prepared by the homogeneous coprecipitation with urea as the precipitant and characterised by XRD, SEM, IR and chemical composition ( n (Ca)/ n (P)). The n (Ca)/ n (P) and phase structure of the powder were found to be affected by the pH value of the system during coprecipitation with urea. The inorganic phase of the composite powder predominately consisted of hydroxyapatite when its n (Ca)/ n (P) was 1 64, the urea concentration was 1 0 mol/L and the pH value of system was 7 2. The inorganic phase of the composite powder in part is consisted of calcium phosphate dibasic(DCPA) when its n (Ca)/ n (P) was 1 42, the urea concenration was 0 5 mol/L and the pH value of system was 6 1. Compared with mechanically mixed HAP/CS powders, the composite powders had new wave peaks at 1 654 cm -1 and 1 560 cm -1 in the IR spectrum.