4668
81.95, X M for (CH3)2Si(0C2H& = 104.20, and X C H * = 11.17 gives C = -0.02. Using these parameters, xM values for dimethyl di-nalkoxysilanes have been calculated and summarized in Table 111. For xM values of acetoxy- and propionoxysilanes of the general formula (CH3),Si(OC=OC,H2n+l)d, Hameka's equation has been used as XM =
aA
+ d D + adE
where
D = 0.25x(Si)
+ x(OCOC,HZ,+l) +
x(Si-OCOC,H,,+,)
+ 1.5~
and
(
E = x S i
