Other polysubstituted norbornenes

For the ROMP of norbomene attached to C o at the 5,6-positions, see Ch.l4. 13.3.6 Other polysubstituted norbornenes 

Various other polymerizable di-, tri-, and tetra-substituted norbornenes are listed in 

For monomers 124 (62% exo-i-CyfTendo-CV-i, 38% endo-i-C -j-exo-CV, 125 (55% exo-CFs, 45% endo-CF ), and 126 (48% exo-(CF2)3, 52% endo-(CF2)3), the first-named exo-isomer is in each case the more reactive so that if polymerization stops short of 100% conversion, the residual monomer is emiched in the other isomer (Seehof 1993b). 

Films of the polymer of 127 exhibit high permeability to gases because of their high fractional free volume. However, this is offset by a somewhat lower discrimination between different gases, as compared with films of other polymers (Teplyakov 1992). 

Polymers of 128 have a narrow MWD if prepared in THF but not if prepared in chlorobenzene. The polymer has a Tg of 110°C and decomposes at 300°C, losing two molecules of acetic acid per repeat unit. It is also readily hydrolyzed to the polydiol, which is soluble in CF3COOH/CHCI3 and degrades with loss of water at 300°C (Bazan 1991b). 

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