Macro-scale Preparation Of Calcium Carbonate Nanofibers

Calcium carbonate is one of the most studied nanomaterials recently.It has been widely applied as promoters in organic or inorganic composites,particularly for aragonite calcium carbonate,because of its advantages of low price and wide sources,in addition to its good filling performance.Current interest on CaCO₃ has been much focused on its modification,which dramatically affects the performance of calcium carbonate for potential industrial applications.This thesis reported the preparation of calcium carbonate nanofibers and its modification with sodium laurate.By controlling the synthetic factors,the optimum conditions to prepare CaCO₃ nanofibers have been determined.Morphology and the crystalline form of the as-prepared CaCO₃ under different conditions have been characterized.Activated modification experiments have been conducted for samples with the uniform shape,the maximum aspect ratio,and the highest content of CaCO₃ aragonite.And further activation of calcium carbonate by sodium laurate have been realized,through characterization of the activation degree,value of oil absorption,differential thermal and thermal gravimetric analysis,and infrared absorption measurements.It has been confirmed that activation of hydrophilic and oleophobic calcium carbonate nanofiber make them lipophilic and hydrophobic,which are beneficial for its application as filler in the polymers.In the microwave-hydrothermal synthesis of CaCO₃ fibers,by changing the dynamics and thermodynamics factors,the synthesis of aragonite nanorods was controlled.The present method of calcium carbonate nanowhiskers has the advantages of high yield,easy operation,and high content of aragonite.For its potential applications in the industry,it will favor to save energy,reduce cost,and environmental friendly.