An amorphous emulsion copolymer consisting of 60 wt% methyl methacrylate (homopolymer Tg= 105 C) and 40 wt % ethyl acrylate (homopolymer Tg= -23 C)

An amorphous emulsion copolymer consisting of 60 wt% methyl methacrylate (homopolymer Tg= 105 C) and 40 wt % ethyl acrylate (homopolymer Tg= -23 C) has been proposed as the basis of a latex paint formulation. A latex consists of tiny (~1-10um) polymer particles suspended in water. After application of the paint, these particles must coalesce to form a film upon evaporation of water.

Calculate the Tg of the copolymer.