Surface nano-structured particles and characterization

Using Ca(OH)(2)-H2O-CO2 system and adjusting suitable technical parameters, by a heterogeneous nucleation principle, nanometer calcium carbonate reactants would deposit, nucleate and grow on surface of original mineral host particles (OMHP) with micron grain size produced by pulverization. Kinds of surface nano-structured particles (SNSP) with rough surface and blunt edges had successfully been prepared in this system. SNSP not only exhibit outstanding properties of nanosized particles, but also improve surface morphology of OMHP. Compared to OMHP, the specific surface area of SNSP can be increased twice or above. After filled in polymer, SNSP could reduce or avoid local stress concentration within composite materials, compared with the result by filling OMHP with sharp edges and flat cleavage plane in polymer. Coinstantaneously, nano-sized particles coated on SNSP surfaces carried by micron-sized particles would evenly be dispersed in polymer matrix. Filling tests show that the polypropylene(PP)-SNSP composites have better mechanical properties and consistency between SNSP and PP matrix than PP-OMHP composites. (c) 2005 Elsevier B.V. All rights reserved.