A new monomer 1,1-bis[(1-adamantyloxy)carbonyl]-2-vinylcyclopropane (3) was readily synthesized and polymerized by radical initiators. Monomer 3 afforded a 1,5-addition polymer selectively and in good conversion, even at high temperatures or low monomer concentrations. Poly(3) is soluble in common organic solvents, but insoluble in ether and methanol. Poly(3) (M n = 51 000 estimated by GPC based on polystyrene standard) exhibited a grass transition at 34 °C and 10% weight loss at 377 °C under nitrogen. Monomer 3 showed a positive volume change (+4.5 ± 1.1%) upon polymerization. This phenomenon can be rationalized by several reasons, such as the depression of recyclization during propagation by bulky ester groups, conversion of the crystalline monomer to the amorphous polymer, and the fact that 3 contains a pair of large spreadable ester groups that may increase the free volume of the polymer matrix. The kinetics of the homopolymerization of 3 with AIBN was investigated in benzene. The rate of polymerization (R p) can be expressed by R p = k[AIBN]0.52[3]1.2, and the overall activation energy E a has been calculated to be 20.8 kcal/mol.

SYNOPSISMethyl trans-P-vinylacrylate (MVA) undergoes radical polymerization with a,a'-azobis(isobutyronitri1e) (AIBN) in bulk and solution. The polymer obtained consists of 85% trans-l,4 and 15% truns-3,4 units. Poly(MVA) (PMVA) is readily soluble in common organic solvents, but insoluble in n-hexane and petroleum ether. PMVA exhibits a glass transition at 6"C, and loses no weight up to 300°C in nitrogen. The kinetics of MVA homopolymerization with AIBN was investigated in benzene. The rate of polymerization (R,) can be expressed by R,, = k[AIBN]o.5[MVA]'.o, and the overall activation energy has been calculated to be 94 kJ/mol. The propagation radical of MVA at 80°C was detected by ESR spectroscopy, which indicated that the unpaired electron of the propagating radical was completely delocalized over the three ally1 carbons. Furthermore, the steady-state concentration of the propagating radical of MVA a t 60°C was determined by ESR spectroscopy, and the propagation rate constant (kp) was calculated to be 1.25 X 10' L/mol.s. Monomer reactivity ratios in copolymerization of MVA ( M 2 ) with styrene ( M , ) are r1 = 0.16 and r2 = 4.9, from which Q and e values of MVA are calculated as 4.2 and -0.32, respectively. 0 1995 John Wiley & Sons, Inc.