Appeal No. 95-1959
Application 07/894,128
that the art relied on strongly suggests the use of
polyolefins in general and polypropylene in particular.
We agree with the examiner's conclusion that
Welborn's teaching that "finely divided olefins such as finely
divided polyethylene" as a support for a complex of a
metallocene and alumoxane is a strong suggestion that
polyolefins, in general, and lower polyolefins, specifically,
would have been expected to be useful supports for catalysts
as claimed. Considered with the fact that Maemoto discloses
that high molecular weight polypropylene is one of many useful
solid materials which serve as a useful support for catalysts
for polymerization of olefins, including polypropylene, we
find that a prima facie case of obviousness is raised by the
references on which the examiner relies. Appellants' brief is
totally silent with respect to the disclosure of Maemoto
except for the terse recognition by appellants at page 3 of
their main brief that Maemoto teaches both polyethylene and
polypropylene have been used as supports for Ziegler-type
catalysts useful in polymerizing olefins.
We find ample motivation to use a supported catalyst
solely from the well-known benefits that a heterogeneous
catalyst is known to engender. Specifically, these benefits
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