Diallyl phthalate (DAP) was polymerized in toluene using dimethyl 2,2'-azobisisobutyrate (MAIB) of high concentrations (0.1-0.9 mol/L) as initiator. The polymerization of DAP of 1.50 mol/L with MAIB of 0.50 mol/L proceeded homogeneously at 80 degrees C without gelation to give soluble polymers in a high yield of 93%. Kinetic results of the homogeneous polymerization at 80 degrees C suggest significant contributions of the degradative chain transfer and the primary radical termination as shown by the rate equation, RP = k [MAIB](0.8)[DAP](1.0) (R-p = polymerization rate). The polymer formed in the polymerization of DAP (1.30 mol/L) with MAIB (0.50 mol/L) at 80 degrees C for 8 h consisted of the DAP units with (17 mol %) and without (47 mol %) double bond and the methoxycarbonylpropyl group (36 mol %) as MAIB-fragment. The large fraction of the incorporated initiator-fragment as terminal group indicates that the polymer has a hyperbranched structure. The film cast from a solution of the hyperbranched poly(DAP) in tetrahydrofuran showed an iridescent color. The confocal scanning laser microscope image of the film revealed that the iridescent film contained the pores of about 1 mu m arranged in an ordered array. (c) 2006 Wiley Periodicals, Inc.