posted on 2006-05-02, 00:00authored byZhihua Chen, John P. Amara, Samuel W. Thomas, Timothy M. Swager
A self-polymerizable AB-type monomer for Diels−Alder (D−A) polymerization was prepared,
and its polymerization was carried out in the melt phase and at high pressure in solution. The former method
generated only low-molecular-weight polymer, but the latter one offered an efficient polymerization with increased
molecular weight, due to the effect of high pressure on reactions with a negative activation volume. A pyridinium
p-toluenesulfonate-catalyzed dehydration reaction of the D−A polymer led to a novel aromatic ladder polymer,
poly(iptycene), which is soluble in common organic solvents and stable up to 350 °C. The NMR and UV−vis
spectra of these polymers match the spectra of their corresponding model compounds, the synthesis of which is
also reported.