纳米分散板片及球形叶蜡石粉体的制备及表征

采用高能球磨、喷雾干燥联用工艺制备了干燥分散的板片与球形叶蜡石粉体，并对所制备的粉体进行了粉晶X射线衍射（XRD）与场发射扫描电镜（FE-SEM）测试。 结果表明：叶蜡石粉体在初步研磨后，叶蜡石的晶型与层状结构特征未发生改变。经喷雾干燥可得到分散的单层叶蜡石纳米板片，板片厚度约为（8±2） nm，其在长轴方向上的粒径大小为0.2～1.2 μm。粉体在较长时间的研磨后，经喷雾干燥可获得均匀粒径的准球形叶蜡石聚集体，单个聚集体微粒直径约2.5 μm，且该聚集体由长径在纳米尺度上的叶蜡石板片团聚而成。此外，XRD测试结果表明喷雾干燥对叶蜡石粉体的晶型并没有明显的影响。

Preparation and characterization of nano-sized pyrophyllite powders with dispersed lamellar or spheroidal structure

Spray drying technique combining with high energy ball milling for the preparation of dry dispersed pyrophyllite powders with lamellar or spheroidal structure was studied，and the prepared powders were characterized by X-ray diffraction（XRD） and scanning electron microscope（FE-SEM）.Results showed that：when grounding for a short time and sprayed drying，dispersed pyrophyllite powders with single lamellar structure were got，at the same time，the lamellar structure and crystalline character are the same as original ones，and the length of single lamellar pyrophyllite at long axis direction was at 0.2~1.2 μm with（8±2） nm in thickness.As the increasing of grinding time，pyrophyllite aggregates with spheroidal structure were achieved through spray drying technique，and the single spheroidal aggregate was about 2.5 μm in diameter，which was composed of nano-sized pyrophyllite lamellars.Furthermore，the results of XRD indicated that the spray drying did not induce the crystal structure change.