The rheokinetics of bulk free radical polymerization has so far been invest
igated only at low degrees of conversion, where the system may be considere
d as Newtonian. In that case the rheokinetic equations can be linearized, y
ielding a simplified expression of the viscosity increase as a function of
time during polymerization. In this paper we extend the rheokinetic approac
h to the study of bulk free radical polymerization at high degrees of conve
rsion, where the rheokinetic equations may not be linearized and the system
must be considered as non-Newtonian. Moreover, the occurrence of the so-ca
lled gel effect complicates the nonlinearity of the rheokinetic problem eve
n more.
The rheokinetic experiments performed show that the gel effect is reduced w
hen the polymerization is performed at high shear rates. At very high degre
es of conversion an onset of irregularities in the viscosity measurements w
as noticed. Possible explanations for these irregularities are discussed.