羟基磷灰石-壳聚糖复合膜旋涂法制备及表征

Preparation and characterization of hydroxyapatite-chitosan composite coatings using a spin-coating technique

为制备高效环保仿生材料,以Na_2HPO_4和Ca(NO_3)_2·4H_2O为原料,采用化学沉淀法合成羟基磷灰石粉体,将粉体超声分散在壳聚糖醋酸溶液中,通过溶液共混和磁力搅拌的方法制备羟基磷灰石-壳聚糖(hydroxyapatite-chitosan,HA-CS)悬浮液.采用旋涂法在不锈钢304基材表面涂覆HA-CS悬浮液,分别在25℃和37℃条件下干燥12 h成膜.将两种HA膜样分别通过X射线衍射、傅立叶变换红外光谱、扫描电子显微镜、X射线能量色散仪和电子拉力机进行测试.结果表明,HA-CS复合材料的拉伸强度达(69.04±1.21)MPa;复合膜结晶度好,黏结致密,无分解,无杂质;旋涂法能更好的使HA均匀分散在CS中,减少HA微粒的团聚和游离;与25℃相比,37℃条件下干燥HA膜有助于HA与CS更多更好地结合,使制得的HA-CS复合膜具有优良性能.为HA-CS复合膜附着金属植入物在人体环境内成功生长提供理论参考.

Based on a chemical precipitation method,the hydroxyapatite powders were prepared using Na_2HPO_4 and Ca（ NO_3）_2·4H_2O as raw materials. The powders were dispersed into chitosan-acetic acid solution with the aid of continuous ultrasonic agitation to prepare hydroxyapatite-chitosan（ HA-CS） suspension via solution blending and magnetic stirring. Hydroxyapatite-chitosan composite coatings were fabricated on 304-type stainless steel substrates by a spin-coating technique,then dried at 25 ℃ and 37 ℃ for 12 h,respectively. The two synthesized samples were characterized and tested by X-ray diffraction（ XRD）,Fourier transform infrared spectroscopy（ FTIR）,scanning electron microscopy（ SEM）,energy-dispersive X-ray spectroscopy（ EDX） and electronic tensile machine. Theresults indicate the tensile strength of HA-CS composites reaches up to（69.04±1.21）MPa,and the coatings display good crystallinity,good adhesion,high purity and little decomposition.In addition,by means of spin-coating technique,HA could be evenly dispersed in CS and there are no aggregated or free HA particles in the coatings.The HA-CS composite coatings show better performance when drying at 37℃ than at 25℃,which is more conducive to combine interaction between HA and CS.