CROSS-LINKING COPOLYMERIZATION OF CYCLIC KETENACETALS WITH LOW SHRINKAGE IN VOLUME

The copolymerization of -4-methylene-3,5,8,10-tetraoxabicyclo[5.3.0]de cane (4) with 9-bismethylene-2,4,8,10-tetraoxaspiro[5.5]undecane (5) w as investigated. While 4 polymerizes after radical attack to form high ly viscous linear polyesters with a number-average molecular weight of 5 000, the addition of 5 in variable amounts leads to insoluble sampl es. It is shown that the material properties can be controlled by usin g various contents of 5 in the storable and persistable monomer 4. Acc ording to the application purpose, it is possible to produce gel-like or rubber-like as well as hard polymer samples.