Statistical group transfer copolymrization of acrylates with methacrylate have been performed for six binary systems using 1 methoxy 2 methyl 1 trimethylsilyloxy propene(initiator) and tetrabutylammonium bibenzoate(catalyst) in THF solution.The copolymer compositions were determined by 1H NMR spectroscopy and the results eval uated by the extented Kelen Tudos method.The monomer pairs concerned are (1) methyl acrylate (MA) and methyl methacrylate (MMA)

(2) ethyl acrylate (EA) and MMA

(3) butyl acrylate(BA) and MMA

(4) MA and ethyl methacrylate (EMA).(5)MA and butyl methacrylate (BMA)

(6) MA and iso-buytl methacrylate (iBMA)

The reactivity ratios were found to be γMA=9.23

γMMA=0.06;γEA=14.15

γMMA=0.01;γBA=7.51;γMMA=0.02;γMA=14.41

γEMA=0.01;γMA=13.96

γBMA=0.23;γMA=0.23;γMA=8.66

γi-BMA=0.08.Anionic copolymerization of EA with MMA and MA with EMA was also carried out to compare with the result of GTP

the date are γEA=9.67

γMMA=0.11;γMA=3.51;γEMA=0.20.It was shown that acrylate is much more reactive than methacrylate for GTP and anionic copolymerization the reactivity ratios are quity diffrernt from unity and show a high similarly.