Appeal No. 95-4036
Application No. 08/137,332
Markle discloses a process for the non-aqueous dispersion
polymerization of a conjugated diolefin monomer, such as
butadiene (Abstract). In the process disclosed in Markle, a
block copolymer dispersing agent is prepared in a separate
process and thereafter added to the polymerization mixture
(see Examples 1-33; col. 29, lines 30-48). Gunesin discloses
a multi-stage process for homopolymerizing anionically
polymerizable vinyl aromatic monomers, such as styrene (col.
1, lines 59-62). The polymeric dispersing agent used in the
process disclosed in Gunesin is “advantageously a block
copolymer” (col. 2, lines 19-26). However, Gunesin fails to
disclose whether the dispersing agent is prepared in a process
separate from the disclosed homopolymerization process or is
prepared in situ.
According to the examiner (Answer, p.3):
The only difference seen between these two patents
and the instantly claimed process is that the Markle
patent teaches the polymerization of the conjugated
diolefin and Gunesin teaches the polymerization of
styrene. The instantly claimed process is directed
to the preparation of a copolymer which contains 35
to 70% of styrene and 30 to 65% of the conjugated
diene monomer. The Examiner maintains however that
given the fact that both of the cited references
teach dispersion polymerization in the presence of
the block copolymer dispersion stabilizer, then it
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