The meso and racemic forms of 1,3-bis(hydroxyphenylmethyl)benzene underwent solvent-free polycondensation with the aid of an acid catalyst giving polyether. Very interestingly, the diastereoisomerism caused a considerable difference in the polymerization behavior. The meso isomer (mp = 96-98 degreesC) was polymerized even at 65 degreesC, whereas the racemic one (mp = 158-160 degreesC) required heating at 100 degreesC to undergo polymerization. However, the latter produced a much higher molecular weight than the former (30,000 vs 4000). The contamination of the meso isomer with the racemic one very sensitively reduced the polymerization temperature: the 98.5% meso monomer underwent polymerization at 50 degreesC. In contrast to solvent-free polymerization, two diastereomeric monomers showed almost identical behavior in solution polymerization. (C) 2003 Wiley Periodicals, Inc.