Appeal No. 95-2035
Serial No. 08/083,864
contacting in a first gas phase, fluidized bed reaction zone under polymerization
conditions, a gaseous monomeric composition comprising a major proportion of
ethylene and, optionally, hydrogen, with a catalyst as hereinafter defined, the
hydrogen/ethylene molar ratio (H /C ratio) being no higher than about 0.35 and the
2 2
ethylene partial pressure being no higher than about 100 psia, to produce said HMW
component associated with catalyst particles, transferring said HMW component
associated with catalyst particles to a second gas phase, fluidized bed reaction zone into
which is also fed hydrogen and a gaseous monomeric composition comprising a major
proportion of ethylene, under polymerization conditions including a H /C ratio of at
2 2
least about 0.6 and at least about 1.5 times that in said first reaction zone, and an
ethylene partial pressure of at least 1.7 times that in said first reaction zone, to produce
said LMW component deposited on and within the HMW component associated with
catalyst particles, said catalyst is selected from the group consisting of 1), 2) and 3),
wherein 1) is a supported Ti/Mg complex precursor prepared by the interacting of a
previously dried hydroxyl-containing, solid, inorganic carrier slurried in a non-polar
solvent with a dialkylmagnesium such that no substantial excess of magnesium remains
in the slurry, and subsequently reacting the resulting supported Mg-containing
intermediate with at least sufficient titanium tetrachloride to react with the hydroxyl
groups on the carrier and form said precursor containing substantially no free TiCl ,
4
said precursor being used together with a hydrocarbyl aluminum cocatalyst; 2) is a
supported Ti/Mg complex precursor prepared by treating a magnesium oxide (MgO)
support with an organic acid, reacting the treated support with titanium tetrachloride,
and pre-reducing the catalyst with an aluminum alkyl, said precursor being used
together with a hydrocarbyl aluminum cocatalyst; and 3) is a catalyst comprising
chromium oxide and tetravalent titanium supported on a refractory oxide in which at
least 75% of its pore volume is in pores of about 200 to 500 Angstroms average pore
diameter.
According to appellants, claims 5, 6 and 12 are to be individually considered separately from
claims 1-4, 13 and 14 (Brief page 3).
The prior art reference of record relied upon by the examiner in rejecting the appealed claims is:
Bailey et al. (Bailey) 4,461,873 Jul. 24, 1984
ISSUES
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