A milky white acrylic based on a modified styrene butadiene copolymer emulsion. The resulting product is a waterproofing and bonding admixture. PROBOND can be mixed with cements, sand-cement mortars and concretes. The mixes produced give high bond strength to existing concrete, masonry and reinforcing steel. Weather resistance is improved due to reduced permeability and thinner sections may be applied due to improved flexural and tensile strengths. Additional improved properties include abrasion resistance, freeze thaw resistance and chemical resistance. PROBOND is suitable for both internal and external use.