The kinetics of polycondensation of aralkyl ethers such as p-di(methoxy) xylene and 4

4/-di(methoxymethyl) diphenyl ether with ten kinds of aro-matics has been studied in the presence of catalysts for Friedel-Crafts reaction. The kinetic expression was found to be V=k [catalyst]0[aromatics]. A series of rate constants and activation energies was calculated. With the nuclear magnetic resonance method

the intermediate product

the carbon-ium ion

was determined

and the following polycondensation mechanism of electrophilic substitution by the carbonium ion was suggested: It was found that the order of reactivity for aromatics reacting with aralkyl ethers is as follows: phenol > p-cresol > 4-tert-butyl-phenol >o-cresol > salicylic acid > acenaphthene > acenaphthylene > 1

2

4

5-tetramethyl-benzene > phenyl ether > naphthalene. The electrophobic group present on the rings of aromatics is favorable to the reactivity of the aromatics.