Recently

polypropylene toughened and strengthened by ultrafine calcium carbonate (CaCO3) has become more and more popular.But for its high surface energy

the compatibility between CaCO3 and polypropylene is poor

so the surface of CaCO3 must be modified before use.In this article

CaCO3 whose surface was pretreated first by acrylic acid (AA) to introduce active double bond groups

was coated chemically by polypropylene wax (PPW) via solid-phase coating polymerization.Compared to traditional solid-phase grafting polymerization

this method has some differences.First

the reaction is not between monomers of small molecular weight and polymer

but between CaCO3 pretreated by AA and PPW; Second

the polymer is usually a solid phase mass under the reaction temperature in the traditional solidphase grafting polymerization

but in this method PPW is in the liquid phase

and the CaCO3 pretreated by AA in the solid phase.Third

in traditional method the reaction is the monomers grafting to the polymer’s surface

but in this method the coating reaction is PPW to the AA on the CaCO3’s surface.As this method can occur in high-speed mixer

it is more convenient and feasible comparing to the traditional grafting reaction which is usually in extruder or reactor.In this article

it is found that coated CaCO3 can stand the treatment of both methyl benzene and dilute hydrochloric acid.Combined the results of FTIR and TGA

the conclusion can be made that PPW has been coated successfully with polyacrylic acid on the surface of CaCO3After filling the coated CaCO3 into polypropylene (PP)

it shows that the impact and tensile properties of PP are improved in somewhat degree.When the content of the coated CaCO3 is 15 phr

the notched impact strength of the PP composite is 1.68 times as high as that of PP.When the content is 10 phr

the tensile strength of PP filled with coated CaCO3 is 1.22 times higher than that of PP filled with uncoated CaCO3 at same contents