Polymerization process

Claim 1

The method of making polymers of 1-olefins of 2-8 carbon atoms and copolymers of said olefins and 1-olefins of 2-20 carbon atoms which comprises polymerizing said olefins under polymerizing conditions with a catalyst prepared by the process of (1) forming a mixture of a finely divided, difficultly reducible, support of the class consisting of silica, alumina, zirconia, thoria, magnesia and mixtures thereof and a chromium +3 derivative of a beta-dicarbonyl compound of the formula ##STR4## or a chromic carboxylate of the formula Cr(OOCR) 3 in an amount to provide about 0.1-30 weight percent of chromium in said catalyst, wherein each R is individually selected from hydrogen or a hydrocarbyl group of 1-20 carbon atoms, (2) heating the mixture of (1) in a stream of dry, inert, and non-oxidizing gas to a temperature of about 230°-540° C., and then (3) forming a second combination by adding a titanium compound to the product of (2) at a temperature ranging from 95°-370° C., said titanium compound having the formula (R') n Ti(OR') m or (R'O) m Ti(OR') n in which R' is the same or different and is hydrogen or a hydrocarbyl group of 1-12 carbon atoms and in which m is 1-4, n is 0-3 and m plus n equals 4 and being present in an amount to give about 0.5-10 weight percent of titanium in said catalyst, and then (4) activating the mixture of (3) by heating in a stream of dry, oxidizing gas to a temperature of about 370°-1100° C.

Claim 2

The method of making polymers of 1-olefins of 2-8 carbon atoms and copolymers of said olefins and 1-olefins of 2-20 carbon atoms which comprises polymerizing said olefins under polymerizing conditions with a catalyst prepared by the process of (1) forming a mixture of a finely divided, difficultly reducible, support of the class consisting of silica, alumina, zirconia, thoria, magnesia and mixtures thereof and a chromium +3 derivative of a beta-dicarbonyl compound of the formula ##STR4## or a chromic carboxylate of the formula Cr(OOCR) 3 in an amount to provide about 0.1-30 weight percent of chromium in said catalyst, wherein each R is individually selected from hydrogen or a hydrocarbyl group of 1-20 carbon atoms, (2) heating the mixture of (1) in a stream of dry, inert, and non-oxidizing gas to a temperature of about 230°-540° C., and then (3) forming a second combination by adding a titanium compound to the product of (2) at a temperature ranging from 95°-370° C., said titanium compound having the formula (R') n Ti(OR') m or (R'O) m Ti(OR') n in which R' is the same or different and is hydrogen or a hydrocarbyl group of 1-12 carbon atoms and in which m is 1-4, n is 0-3 and m plus n equals 4 and being present in an amount to give about 0.5-10 weight percent of titanium in said catalyst, and then (4) activating the mixture of (3) by heating in a stream of dry, oxidizing gas to a temperature of about 370°-1100° C.