Interference 103,482
I), states (Ewen et al., U.S. 4,892,851, col. 1, l. 16-27;
emphasis added):
The present invention provides a catalyst and
process
for polymerizing olefins having three or more carbon
atoms
to produce a polymer with a syndiotactic stereochemical
configuration. The catalyst and process are particularly
useful in polymerizing propylene . . . .
As known in the art, syndiotactic polymers have a
unique stereochemical structure in which monomeric units
having enantiomorphic configuration of the asymmetric
carbon
atoms follow each other alternately and regularly in the
macromolecular main chain.
Ewen et al. depict the structure and define the molecular
units of syndiotactic polymers using general Fischer
projection formulas and NMR nomenclature (Ewen et al., U.S.
4,892,851,
col. 2, l. 9, to col. 3, l. 6).
We find that persons skilled in the art would have
considered broad teachings to polymerize olefins in their
functional context. Ewen defines isotactic polypropylene as
containing “repeating units with identical configurations and
only a few erratic, brief inversions in the chain”,
represented by the Fischer projection \ \ \ \ \ and
designated in Bovey’s NMR nomenclature as mmmm (Ewen U.S.
98
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