Schiff bases of types 1, 2, and 3, easily prepared by the condensation of primary amines with pyridine-2-carboxaldehyde, glyoxal, or 2-acetylpyridine, respectively, are described as ligands for a copper(I) catalyst in the atom transfer polymerization of a range of methacrylates in toluene and xylene solution. Increasing the length of the alkyl group on ligands of type 1 increases the solubility of the catalyst in nonpolar solvents. The rate of polymerization increases on going from R = ethyl to propyl; however, on increasing the length of R further, we see no effect on the rate. The molecular weight distribution is narrow for all ligands where R = n-alkyl, and the number-average molecular weight (M n) increases linearly with conversion. A decrease in rate and a loss of control are observed when branching is introduced in the α-position of the side chain. The polymerization is approximately first order in initiator, 0.90 ± 0.22, CuBr, 0.90 ± 0.13, and methyl methacrylate, 0.93 ± 0.01. Polymerization with CuBr in conjunction with diazabutadiene ligands does not proceed very effectively, due to the high stability of the copper(I) complexes with regard to oxidation. The mechanism of the reaction is complex and may differ on subtle changes in ligand, metal, solvent, etc. The ligand systems presented in this paper offer a wide range of versatility when choosing the most effective system for a particular application. The Schiff base ligands, when used as described, provide an excellent method for achieving the controlled polymerization of a wide range of methacrylates at relatively mild temperatures in hydrocarbon, noncoordinating, solvents.

Reactivity ratios have been determined for the monomer pair methyl methacrylate and n-butyl methacrylate under a range of polymerization conditions. The value of using reactivity ratios as a mechanistic probe is discussed. Reactivity ratios determined where M1 = MMA and M2 = n-BMA are 1.04, 0.81, classical anionic; 1.10, 0.72 , alkyllithium/trialkylaluminum initiated; 1.76, 0.67, group transfer polymerization; 0.98, 1.26, atom transfer radical polymerization; 0.75, 0.98, catalytic chain transfer; and 0.93, 1.22, classical free radical polymerization. The data suggest ATRP and CCTP proceed via radical type propagation. Li/Al-initiated polymerization undergoes an anionic mechanism, while strong evidence is found for an associative, catalyst dependent mechanism for GTP. Galvinoxyl is demonstrated to inhibit GTP as well as free radical polymerization, and it is suggested that neither the use of inhibition nor polymer stereochemistry can be used to distinguish between anionic and radical processes.

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The surfactant-mediated desorption of adsorbed poly(vinylpyrrolidone), PVP, from anionic silica surfaces by sodium dodecyl sulfate, SDS, was observed. While photon correlation spectroscopy shows that the size of the polymer-surfactant-particle ensemble grows with added SDS, a reduction in the near-surface polymer concentration is measured by solvent relaxation NMR. Volume fraction profiles of the polymer layer extracted from small-angle neutron scattering experiments illustrate that the adsorbed polymer layer has become more diffuse and the polymer chains more elongated as a result of the addition of SDS. The total adsorbed amount is shown to decrease due to Coulombic repulsion between the surfactant-polymer complexes and between the complexes and the anionic silica surface.

The synthesis and characterisation of a series of novel bis(imine)copper(I) complexes and their use in atom‐transfer polymerisation of methyl methacrylate is described. Several N‐alkyl‐(2‐pyridyl)methanimines (alkyl = n‐butyl, isobutyl, sec‐butyl, n‐propyl) and N‐(n‐propyl)‐1‐(2‐pyridyl)ethanimine as ligands have been fully characterised. Three bis[N‐alkyl‐(2‐pyridyl)methanimine]copper(I) complexes, [Cu{(C5H4N)CH=N(iBu)}2][BF4], [Cu{(C5H4N)C(CH3)=N(nPr)}2][PF6], and [Cu{(C5H4N)CH=N(sBu)}2][BF4] have been structurally characterised; all having a distorted tetrahedral arrangement of co‐ordinating nitrogen atoms surrounding the metal centre. All of the catalysts were found to be effective atom‐transfer polymerisation catalysts for the polymerisation of MMA in hydrocarbon solution. However, it was discovered that the performance of the catalysts containing n‐alkyl substituents was superior to those containing branched alkyl substituents. The presence of branching in the alkyl substituent results in a reduction of reaction rate and a corresponding broadening of the polydispersity index.