Is it possible to combine materials into a pattern at runtime?

I'd like to be able to combine two or more materials into a pattern and be able to assign that pattern as a material to a MeshRenderer. As a simple example; take two materials A and B and create a checkerboard material out of these that would show A when u < 0.5 and v < 0.5 or u > 0.5 and v > 0.5 otherwise it would show material B. I know this could be done with a shader and two textures but is it possible to do this with two existing materials?