NEW LADDER POLYMERS VIA REPETITIVE DIELS-ALDER REACTION UNDER HIGH-PRESSURE

The synthesis of a new ladder-type polymer by repetitive Diels-Alder reaction is described. The ''bis-diene'' 1 was treated with 1,4:5,8-bisepoxy-9,10-dihexyl-1,4:5,8-tetrahydroanthracene (2) at high pressure (7-8 kbar). Under these conditions the formation of polymer 5 was obtained. The influence of concentration, solvent, and temperature on the polymer-forming reaction is discussed. The polymer was characterized by size-exclusion chromatography, by NMR spectroscopy, and by DSC and thermogravimetric methods. An attempt is made to solve the complex stereochemistry by the preparation of model compounds 7a and 7b.