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The synthesis of hard-core/soft-shell calcium carbonate(CaCO_3)/poly(methyl methacrylate)(PMMA)hybrid structured nanoparticles(<100nm) by an atomized microemulsion polymerization process is reported.The polymer chains were anchored onto the surface of nano-CaCO_3 through use of a coupling agent,triethoxyvinyl silane(TEVS).Ammonium persulfate(APS),sodium dodecyl sulfate(SDS)and n-pentanol were used as the initiator,surfactant and cosurfactant,respectively.The polymerization mechanism of the core-shell latex particles is discussed.The encapsulation of nano-CaCO_3 by PMMA was confirmed using a transmission electron microscope(TEM).The grafting percentage of the core-shell particles was investigated by thermogravimetric analysis(TGA).The nano-CaCO_3/PMMA core-shell particles were characterized by Fourier transform infrared(FTIR) spectroscopy and differential scanning calorimetry(DSC).The FTIR results revealed the existence of a strong interaction at the interface of the nano-CaCO_3 particle and the PMMA,which implies that the polymer chains were successfully grafted onto the surface of the nano-CaCO_3 particles through the link of the coupling agent.In addition,the TGA and DSC results indicated an enhancement of the thermal stability of the core-shell materials compared with that of the pure nano-PMMA.The nano-CaCO_3/PMMA particles were blended into a polypropylene(PP) matrix by melt processing.It can also be observed using scanning electron microscopy(SEM) that the PMMA chains grafted onto the CaCO_3 nanoparticles interfere with the aggregation of CaCO_3 in the polymer matrix(PP matrix) and thus improve the compatibility of the CaCO_3 nanoparticles with the PP matrix.
The synthesis of hard-core / soft-shell calcium carbonate (CaCO_3) / poly (methyl methacrylate) (PMMA) hybrid structured nanoparticles (<100 nm) by an atomized microemulsion polymerization process was reported.The polymer chains were anchored onto the surface of nano Ammonium persulfate (APS), sodium dodecyl sulfate (SDS) and n-pentanol were used as the initiator, surfactant and cosurfactant, respectively. The polymerization mechanism of the core- shell latex particles is discussed. The encapsulation of nano-CaCO 3 by PMMA was confirmed using a transmission electron microscope (TEM). The grafting percentage of the core-shell particles was investigated by thermogravimetric analysis (TGA). The nano-CaCO 3 / PMMA core -shellarticles were characterized by Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). The FTIR results revealed the existence of a strong interaction at the interface of the nano-CaCO_3 particl e and the PMMA, which implies that the polymer chains were successfully grafted onto the surface of the nano-CaCO 3 particles through the link of the coupling agent. In addition, the TGA and DSC results indicate an enhancement of the thermal stability of the core- shell materials compared with that of pure nano-PMMA.The nano-CaCO 3 / PMMA particles were blended into a polypropylene (PP) matrix by melt processing. It can also be observed using scanning electron microscopy (SEM) that the PMMA chains grafted onto the CaCO 3 nanoparticles interfere with the aggregation of CaCO 3 in the polymer matrix (PP matrix) and thus improve the compatibility of the CaCO 3 nanoparticles with the PP matrix.