摘要
采用液相碳化法制备不同形貌的纳米碳酸钙颗粒,并用TEM、SEM、XRD和IR等先进测试方法对产物进行表征。研究了十二烷基硫醇接枝聚甲基丙烯酸的加入对纳米碳酸钙制备过程的影响,结果表明,十二烷基硫醇接枝聚甲基丙烯酸能够促进碳酸钙的晶体成核,抑制晶体生长,从而可对产物的形态结构进行有效调控。添加量为2.24%(质量分数,下同)时,生成了粒径约为20～50nm的立方状纳米碳酸钙;添加量为3.36%及以上时,生成了不同粒径的棒状纳米碳酸钙。分析了立方状和棒状纳米碳酸钙的形成机理,发现这可能与PMAA-DDT的分子结构与形状有关。同时研究了反应温度对纳米碳酸钙形态的影响,发现在较高温度下碳酸钙粒径增大,团聚严重,升高反应温度不利于控制纳米碳酸钙形貌,95℃时出现文石相碳酸钙。
Calcium carbonate nanoparticles with different morphology are obtained in the presence of dodecylthioether end functionalized poly（methacrylic acid） （PMAA-DDT） via a carbonation route. The effects of PMAADDT on carbonation process of calcium carbonate are analyzed by transmission electron microscopy（TEM）, scanning electron microscopy（SEM）, Fourier transform infrared spectroscopy（FT-IR） and X-ray diffraction（XRD）. The results demonstrate that the nucleation rate increase and the growth rate decrease when PMAA-DDT is added to the reaction slurry, so the morphology of calcium carbonate can be controlled. Cubic CaCOa particles with an average size of 20～50nm are formed at an additive concentration of 2. 24wt%. While further increase in additive concentration to 3.36wt% or more rod-shaped CaCO3 nanoparticles with different particle size can be obtained. The nucleation-growth mechanism for cubic and rod-shaped CaCO3 nanoparticles is discussed. This may be associated with the structure and shape of PMAA-DDT. The influence of reaction temperature on morphology of CaCO3 is also studied. Results show that morphology is not easy to control and agglomerate calcium carbonate is obtained at higher temperature. Aragonite is obtained at 95℃.
出处
《材料导报》
EI
CAS
CSCD
北大核心
2010年第2期87-90,共4页
Materials Reports
基金
863计划资助项目(2007AA05Z420)
973计划资助项目(2007CB607606)
关键词
纳米碳酸钙
十二烷基硫醇接枝聚甲基丙烯酸
碳化法
形貌
晶型
calcium carbonate nanoparticles, dodecylthioether end functionalised poly（methacrylic acid）, carbonization, morphology, polymorph
