Free?radical propagation rate coefficients

The pulsed laser polymerization-size-exclusion chromatography (PLP-SEC) technique has become the International Union of Pure and Applied Chemistry (IUPAC)-recommended method for accurate determination propagation rate coefficients, kp, radical polymerization. fundamental insight provided by Heuts, Gilbert, Radom into relevance transition state dynamics allows an adequate understanding dependence kp on chain length, solvent environment, monomer conversion. associated entropic effects are particularly pronounced in aqueous solution, but also found less polar media with non-polar monomers. Moreover, these arguments applicable towards interpretation copolymerization reactivity ratios. addition sodium hydroxide to solutions (meth)acrylic acid yields partially even fully ionized systems clearly reduced which indicates action repulsive forces between equally charged species. Increasing concentration as well salts may reverse this effect increase due counterion activity.