Atom transfer radical polymerization (ATRP) of n-butyl methacrylates (BMA) has been achieved with ethyl 2-bromoisobutyrate [(CH3)2CBrCO2C2H5] as an initiator and CuBr

2

2′-bipyridine(bpy) and aluminum triisopropoxide [Al(OiPr)3] as a ternary catalyst system in cyclohexanone.The kinetics and mechanism of polymerization were discussed in detail.Al(OiPr)3

a bulky Lewis acid

which is used as a catalytic promoter

may coordinate the ester carbonyl of the initiator and polymer and activate the carbon-bromine bond.Therefore

BMA can be polymerized at a lower temperature.The influence of Al(OiPr)3 on polymerization rate and molecular weight distributions were also studied.The polymerization of BMA became sloer and more controlled with CuBr2 than without CuBr2 In the absence of CuBr2

the polymerization of BMA were the rapider and less controlled at 28℃ In the presence of CuBr2

the polymers produced at 52℃ had narrow molecular weight distributions (MWD=1.2～1.5) and designed molecular weights which were nearly proportional to mononer conversion.The logarithmic conversion data plotted against time (ln([M]0/[M]) versus time) followed a current first order kinetics.