Summary: A new kind of rubber powder with “salami” structure (RPS) was prepared by spray drying the mixture of styrene‐butadiene rubber latex and nano‐CaCO3 slurry. It was found that RPS is an effective toughener with synergistic toughening effect on poly(propylene) (PP). The Izod impact strength of PP/RPS blend is not only higher than that of PP/rubber powder or PP/nano‐CaCO3 blends, but also higher than that of a PP/rubber powder/CaCO3 blend. TEM images show that the microstructure of the PP/RPS blend is an “island‐sea” structure with “salami” structure in RPS, in which nano‐CaCO3 particles are embedded in styrene‐butadiene rubber particles. The relationship between properties and microstructure has been studied by using TEM, SEM, DSC, etc.
