Random copolymerization have been performed for five binary systems using 1 methoxy 2 methyl 1 trimethylsilyloxy propene(initiator) and tetrabutylammonium bibenzoate (catalyst) in tetrahydrofuran solution.The copolymer compositions were determined by elemental analysis for nitrogen and the results calculated by the Kelen Tudos method.The monomer pairs concerned are (1) acrylonitrile (AN) and methyl methacrylate (MMA)

(2)AN and ethyl methacrylate (EMA)

(3)AN and butyl methacrylate (BMA)

(4)AN and butyl acrtlate(BA)

(5)AN and dibutyl maleate(DBM).The reactivity ratios determined in this study are:(1)rAN=10.22

rMMA=0.07;(2)rAN=5.68

rEMA=0.16;(3)rAN=8.59

rBMA=0.09;(4)rsub>AN=4.08

rBA=0.06;(5)rAN1.38

rDBM=0.06.The results show that GTP is similar to anionic polymerization with respect to the reactivoty ratios.