The present invention relates to a polymer bead material that are characterised by having pore sizes that can be pre-determined and that can be obtained with a narrow distribution of such pore sizes created by use of sacrificial filler materials within the polymer material. The invention also discloses processes for production of the material as spherical or approximately spherical beads or resins with predefined sizes. Also, the invention relates to the preparation of molecularly imprinted polymer materials that are created by the said method. Further the invention relates to the use of said polymer materials for separation, detection, catalysis or entrapment of chemicals, metal ions, inorganic compounds, drags, peptides, proteins, DNA, natural and artificial polymers, natural or artificial compounds, food or pharma products, viruses, bacteria, cells and other entities.