The monomer 2-allylphenoxyorganocyclotriphosphazene was synthesized by reacting hexachlorocyclotriphosphazene with 2-allylphenol, phenol and 2,2,2-trifluoroethanol by phase transfer catalysis in a dichloromethane/alkaline solution. The copolymerizations of 2-allylphenoxyorganocyclotriphosphazene with styrene, methyl methacrylate and vinylbenzyl chloride were investigated. Nine copolymers of 2-allylphenoxyorganocyclotriphosphazene were identified in the solution. These copolymers were characterized by using light scattering, viscometry and P-31 n.m.r. spectroscopic techniques. The micelles were observed to hydrodynamically and thermodynamically behave as impermeable spheres. The structure of the micellar shell was determined. The translational diffusion coefficient, Mark-Houwink constants, hydrodynamic radius, micellar weight, aggregation number, characteristic ratio and intrinsic viscosity were obtained. The chains of copolymer were observed to have a high degree of stiffness and a lack of rotational freedom in solution.