Modification of calcium carbonate particles with surfactant significantly improves the properties of polyvinyl
chloride (PVC). Hydrophobic spherical CaCO3 particles were prepared in the presence of dodecyl dihydrogen
phosphate (DDP) by a carbonation method. In the process, DDP was used as an organic substrate to induce the
nucleation and growth of calcium carbonate. The operating parameters such as temperature and the dosage of
the organic substrate were varied to study their influences on the active ratio and contact angle of calcium
carbonate particles. The surface property of CaCO3 particles was changed from hydrophilic to hydrophobic
when the dosage of DDP to CaCO3 changed from 0 to 2%. The contact angle of modified CaCO3 particles was
119.51°. Moreover, X-ray diffraction (XRD), FT-IR spectrums and thermogravimetry analysis (TGA) were
employed to characterize the obtained products. The schematic illustration for interaction between the organic
substrate and inorganic mineral in aqueous mediumwas showed in the end. The synthesized CaCO3 was applied
to polyvinyl chloride (PVC) to improve its mechanical properties. The properties of PVC/CaCO3 composites have
been tested such as tensile strength, impact strength, Young's modulus and SEM.