SIMULTANEOUS CATIONIC HOMOPOLYMERIZATIONS OF VINYLCARBAZOLE AND OXETANE

Polymerization of vinylcarbazole and oxetane was initiated in nitrobenzene by tetranitromethane-(TNM). It was shown that nitroform is the probable initiator, the latter being formed by the sequence C(NO2)4 + CH2=CHN< → C(NO2)3- + NO2CH2CH+N< → HC(NO2)3 + NO2Ch=Chn< The uptake of both monomers was followed by nmr technique; thus – d[V]/dt and – d[Ox]/dt were determined simultaneously. The reaction produces a mixture of two homopolymers. Although the presence of oxetane reduced the rate of vinylcarbazole polymerization by a factor of 30, it did not affect its molecular weight. The polymerization of vinylcarbazole is first order in TNM and in monomer; the termination apparently involves a “wrong” monomer addition. The polymerization of oxetane requires the presence of vinylcarbazole; TNM alone does not initiate the reaction. Its rate is proportional to [TNM]1/2, [V]1/2 and [Ox], indicating bimolecular termination-arising from combination of the ions. The kinetic results demonstrate that oxetane is about 30 times more reactive toward nitroform than vinylcarbazole. © 1969, American Chemical Society. All rights reserved.