Radical Polymerization Of Butyl Methacrylate Research Articles

Rheological study of the mechanism of gel-effect in radical polymerization of butyl methacrylate in bulk

Dependences were derived of maximum Newtonian viscosity η 0 and the initial modulus of high-elasticity G 0 of reaction systems on the degree of transformation q during radical polymerization in bulk of butyl methacrylate. A correlation was found between boundaries of linear sections of dependences of log η 0-log q and boundaries of the transitional range on kinetic curves of polymerization. Comparison of typical degrees of conversion determined by rheological and kinetic methods with boundaries of transition from dilute to concentrated polymer solutions in the monomer and results of measuring G 0 enabled us to establish that the start of the gel-effect is due to the formation of the so-called “linkage network” in the solution.

The effects of butyl- o-titanates on the radical polymerization of butyl methacrylate

n-Butyl-and tert. butyl- o-titanate (NBT and TBT) added to n-butyl methacrylate (NBM) act as weak polymerization inhibitors and chain transfer agents. NBT and TBT produce a 1000 fold increase in the rate of the decomposition of ketone- and hydro-peroxides, while NBT produces a 50–100 fold increase in decomposition diacyl peroxides while simultaneously reducing the initiation efficiency by one order of magnitude so that the intiator is rapidly exhausted and the polymerization stops after low conversions. Both, NBT and TBT, do not affect the initiation by dialkyl peroxides.