LATEX STYRENE BUTADIENE POWDERS AND ASPHALT COMPOSITION COMPRISING SAID POWDER

Provided herein are dispersible copolymer powders and asphalt compositions comprising the same. The dispersible copolymer powders comprise a core polymer having a glass transition temperature (Tg) of 40° C. or less and a shell comprising a water soluble protective colloid polymer having a Tg of 50° C. or greater. The core polymer can be derived from a vinyl aromatic monomer, a 1,3-diene monomer, and optionally one or more ethylenically-unsaturated monomers. The protective colloid polymer can be selected from a polyvinyl alcohol, a polyvinyl pyrrolidone, a polysaccharide, other water soluble polymers, or a combination thereof. Methods of preparing a styrene-butadiene modified asphalt without significantly increasing the viscosity, comprising adding the dispersible copolymer powder to an asphalt composition, wherein the addition of the copolymer polymer increases the viscosity of the asphalt by 100% or less at 135° C. within 2 hours of mixing are also described herein.