LAUSR

− Spherical phenolic resin beads were synthesized by suspension polymerization at 98 oC from phenol, ortho-cresol, formaldehyde, with triethylamine as a basic catalyst, and spherical phenol-cresol copolymer resin beads with relatively low crosslinking density as well. Phenol reacts with formaldehyde at two orthoand one parapositions to form a crosslinked structure, but ortho-cresol instead of phenol reduces the crosslinking density during copolymerization due to the methyl group at a orthoposition. As a result, spherical phenol-cresol copolymer beads showed more shrinkage with decreasing apparent density compared to the spherical phenol beads when carbonized at 700 oC under nitrogen. As the molecular weight of the cresol oligomer increases, the pore radius of the carbonized copolymer beads decreases, which is consistent with the density and shrinkage results. It was confirmed that the characteristics such as density decrease, shrinkage, yield and so on during carbonization can be controlled by controlling the degree of crosslinking of the spherical phenolic resin particles with cresol.