Patent Interference No. 103,812
chain terminating agent. However, both U.S. Patent Nos. 4,431,793 and 5,025,081 recognize
that phenol can be used as a chain terminating agent. See RX 7, col. 1, lines 17-20; RX 8, col. 4,
lines 25-32.
Scholl argues that the benzotriazole endcapping agents of the count have both acid and
hydroxyl functionalities. Scholl relies on U.S. Patent No. 4,153,780 to Narita et al. (RX 2) to
establish that the endcapping agents of the count could chemically bind to the condensation
product by an ester linkage through the hydroxyl group, rather than the acid substituent, of the
phenolic substituent of the endcapping agents. See SB, pp. 9-10.
Specifically, Narita et al. disclose that benzotriazole compounds are useful in adjusting
the molecular weight of polycarbonate compositions. According to Narita et al., the hydroxyl
group of the benzotriazole compounds reacts with the terminal chloroformate group of the
polycarbonate and binds chemically to the termini of the polycarbonate. Through this reaction,
the molecular weight of the polycarbonate is controlled. See generally RX 2, col. 3, lines 8-45.
Rosenquist argues that the phenolic hydroxyl group in the endcapping agent of the count
is hindered, and therefore, would not react with the condensation product to provide an
endcapping function. According to junior party Rosenquist (RRB, p. 19):
If the hindered phenolic hydroxy group were reacting with the polycarbonate (i.e.
with the phosgene component), the benzotriazol benzene propanoic acid would
have been difunctional (i.e. hydroxy and carboxylic acid functionality), and
would then have functioned as a comonomer, and the resultant molecular weights
of the polymers would have been many fold higher than measured and reported at
RX-6, page 305. This matter is fully explained by Dr. Rosenquist at RR-009 at
par. 11.
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