Abstract: Using phenol and formaldehyde as raw materials, the millimeter-sized phenolic resin spheres were prepared by suspension polymerization. The effects of four influencing factors on the sphere diameter and sphericity were investigated. They were formaldehyde to phenol ratio (n_F:n_P), the amount of dispersant(PVA), curing agent(HMTA) and stirring speed. The results showed that the optimum process conditions were as follows: formaldehyde to phenol ratio was 0.9:1, the mass fraction of added PVA was 8%, HMTA was 10% and stirring speed was 300-360 r/min. Under this condition, the average sphere diameter of phenolic resin spheres was 1.04 mm and the average sphericity was 0.97. Industrial analysis and elementary analysis showed that phenolic resin spheres were free of ash and contained 74.27% carbon. In addition, the result of thermogravimetric analysis indicated that carbon yield was up to 62%.

Key words: phenolic resin spheres, suspension polymerization, distribution of sphere diameter, average sphere diameter, sphericity