Synthesis and rheological properties of poly(styrene-co-butyl methacrylate) as an ink vehicle

Poly(styrene-co-butylmethacrylate) as an ink vehicle was synthesized using free radical polymerization. The molecular weights and monomer ratios in copolymers were determined. According to the results, the molecular weight could be controlled by the addition of a chain transfer agent and the copolymer ratio was nearly the same as the mole ratio of the monomer feed. The effect of the copolymer ratio on the rheological property was also studied. The polymer melt resembled a very viscous Newtonian fluid at a rate above the critical shear rate. Also, it is possible to synthesize a copolymer whose activation energy value is independent of the shear rate. The viscosity and melt behavior of the copolymer can be controlled with proper blending.