# US 5,705,576 A · Process for controlling production of in-situ thermoplastic polyolefins and products > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,705,576 A - Document ID: US5705576A - Status: Granted - Kind: A - Application number: 08/439,924 - Filed: 1995-05-12 - Granted: 1998-01-06 - Earliest claimed: 1992-11-12 - Assignees: Quantum Chemical Corporation - Inventors: Charles K. Buehler; Thaddeus W. Klimek - Web page: https://patentgrep.com/patent/US5705576A ## CPC - C08J 5/18: Manufacture of films or sheets - C08F 210/06: Propene - C08F 210/16: Copolymers of ethene with alpha-alkenes, e.g. EP rubbers - C08F 297/083: {the monomers being ethylene or propylene} - C08J 2323/10: Homopolymers or copolymers of propene - Y10S 526/901: Monomer polymerized in vapor state in presence of transition metal containing catalyst - C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29) - C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS - Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS ## Abstract An improved gas-phase polymerization process for producing in-situ thermoplastic polyolefins in multiple reactors using high activity Ti/Al catalysts is provided. The improvement consists of developing a control parameter derived from eight integrated regions of the copolymer .sup.13 C NMR spectrum, defining the limits of the control parameter for the process, and operating the process to maintain the parameter within the defined limits. This is accomplished by adjusting the amount of ethylene fed to the secondary reactor and adjusting other process variables as required. Thermoplastic polyolefins, i.e., modified polypropylenes, having reduced hexane extractables and improved paint adhesion are also disclosed. ## Claims ### Claim 1 In a gas-phase process for producing thermoplastic polyolefins in multiple reactors wherein propylene is homopolymerized in a first reactor maintained at 50.degree. C. to 100.degree. C. and 250 psig to 650 psig in the presence of a supported high activity Ziegler-Natta catalyst comprised of a titanium-containing catalyst component and organoaluminum cocatalyst component and the product produced therein is fed to a second reactor maintained at 25.degree. C. to 80.degree. C. and 100 psig to 500 psig where propylene is copolymerized with ethylene, to obtain high rubber content modified polypropylene having reduced hexane extractables and improved paintability, the improvement comprising: (a) calculating a control parameter Q.sub.c using eight integrated areas of the .sup.13 C NMR spectrum corresponding to molecular structural features for copolymers of propylene and ethylene in accordance with the equation: ##EQU3## where A=1.167R.sub.1 +0.75R.sub.2 +1.5R.sub.3 +1.5R.sub.4 +1.167R.sub.8 B=0.667R.sub.1 +0.5R.sub.2 +R.sub.5 +R.sub.6 +R.sub.7 +0.667R.sub.8 and R.sub.1 through R.sub.8 have the following peak assignments: ______________________________________ R.sub.1 37.9 PPM R.sub.2 37.5 PPM R.sub.3 33.2 PPM R.sub.4 31.2-30.9 PPM R.sub.5 30.4 PPM R.sub.6 30.0 PPM R.sub.7 27.4 PPM R.sub.8 24.9 PPM; ______________________________________ (b) selecting limits of Q.sub.c for the process within the range 0.65 to 1.0; (c) determining the actual value of the parameter, Q.sub.A, for the polymer obtained from the second reactor; and (d) controlling the ethylene feed to maintain Q.sub.A within the limits defined in (b). ### Claim 2 (depends on 1) The process of claim 1 wherein the support is treated to remove or react surface hydroxyl groups prior to contacting with the titanium-containing catalyst component. ### Claim 3 (depends on 1) The process of claim 1 wherein the first and second reactors are stirred, fixed-bed reactors. ### Claim 4 (depends on 1) The process of claim 1 wherein one or more .alpha.-olefins containing from 4 to 8 carbon atoms are included in the polymerization. ### Claim 5 (depends on 2) The process of claim 2 wherein an amount of ethylene sufficient to incorporate from 15 to 30 weight percent ethylene in the polymer is fed to the second reactor. ### Claim 6 (depends on 5) The process of claim 5 wherein an amount of hydrogen ranging from 0.1 to 5 mol percent is included in the first reactor and an amount of hydrogen from 1 to 10 mol percent is included in the second reactor. ### Claim 7 (depends on 6) The process of claim 6 wherein the operating limits for Q.sub.c is in the range from 0.75 to 0.98. ### Claim 8 (depends on 7) The process of claim 7 wherein the first and second reactors are stirred, fixed-bed reactors. ### Claim 9 (depends on 6) The process of claim 6 wherein the titanium-containing catalyst component is obtained by (a) treating silica to remove surface hydroxyl groups by calcining said silica in an inert atmosphere and treating with a hexaalkyldisilazane; (b) contacting said treated silica with (1) a modifying compound selected from the group consisting of silicon halides, boron halides, aluminum halides, alkyl silicon halides and mixtures thereof; and (2) at least one hydrocarbon soluble magnesium-containing compound selected from the group consisting of hydrocarbyloxy magnesiums, hydrocarbyloxymagnesium halides and mixtures thereof; said contacting steps (1) and (2) occurring in random order; (c) contacting said product of step (b) with at least one titanium-containing compound having the structural formula Ti(OR).sub.n X.sub.m, where R is aryl, alkyl or mixtures thereof; X is halogen; n is an integer of 1 to 4; m is 0 or an integer of 1 to 3; and the sum of m and n is 4; and (d) treating the product of step (c) with a titanium-containing compound having the structural formula TiX.sup.1.sub.p (OR.sup.1).sub.q, where X.sup.1 is halogen; R.sup.1 is aryl or alkyl; p is an integer 1 to 4; q is 0 or an integer of 1 to 3; and the sum of p and q is 4, with the proviso that the titanium-containing compound of this step is not the same as the titanium-containing compound of step (c). ### Claim 10 (depends on 9) The process of claim 9 wherein an alkylaluminum or alkylaluminum halide and an optional silane cocatalyst of the formula R'.sub.a (OR").sub.4-a Si where R' and R" are hydrocarbyl groups are present with the titanium-containing catalyst component. ### Claim 11 (depends on 6) The process of claim 6 wherein the titanium-containing catalyst component is obtained by treating silica to remove surface hydroxyl groups by calcining in an inert atmosphere and treating with a hexaalkyldisilazane and reacting said modified silica support having a selective distribution of reactive hydroxyl groups with a magnesium compound reactive with said surface hydroxyl groups, optionally reacting the thus obtained product with a silicon halide, alkyl silicon halide, boron halide or aluminum halide, further reacting the so-produced first material with a tetra-substituted organo halogen-free titanium compound wherein the organic moiety sterically hinders accessibility of said organo titanium compound to the reactive sites on the modified silica support and thereafter reacting the so-produced second material with a titanium halide. ### Claim 12 (depends on 11) The process of claim 11 wherein an alkylaluminum or alkylaluminum halide and an optional silane cocatalyst of the formula R'.sub.a (OR").sub.4-a Si where R' and R" are hydrocarbyl groups are present with the titanium-containing catalyst component. ### Claim 13 (depends on 6) The process of claim 6 wherein the titanium-containing catalyst component is obtained by (a) contacting silica, in random order, with (1) at least one hydrocarbon soluble magnesium-containing compound; and (2) a first modifying compound selected from the group consisting of silicon halide; boron halides, aluminum halides and mixtures thereof followed by a second modifying compound selected from the group consisting of a silane of the formula SiH.sub.1 X.sup.2.sub.s, where X.sup.2 is halogen; r is an integer of 1 to 3; and s is an integer of 1 to 3, with the proviso that the sum of r and s is 4, hydrogen halides having the structural formula HX.sup.3, where X.sup.3 is halogen, and mixtures thereof, said sequence of contact of silica with said components (1) and (2) being random; (b) contacting the product of step (a) with a first titanium-containing compound having the structural formula Ti(OR).sub.m X.sub.n, where R is hydrocarbyl or cresyl; X is halogen; m is an integer of 1 to 4; and n is 0 or an integer of 1 to 3, with the proviso that the sum of m and n is 4; and (c) contacting the product of step (b) with a second titanium-containing compound having the structural formula TiX.sup.1.sub.p (OR.sup.1).sub.q, where X.sup.1 is halogen; R.sup.1 is hydrocarbyl; p is an integer of 1 to 4; q is 0 or an integer of 1 to 3, with the provisos that the sum of p and q is 4 and that said first titanium-containing compound and said second titanium-containing compound are different. ### Claim 14 (depends on 13) The process of claim 13 wherein an alkylaluminum or alkylaluminum halide and an optional silane cocatalyst of the formula R'.sub.a (OR").sub.4-a Si where R' and R" are hydrocarbyl groups are present with the titanium-containing catalyst component. ### Claim 15 (depends on 6) The process of claim 6 wherein the titanium-containing catalyst component is obtained by (a) treating an inert inorganic support with hexamethyldisilazane to remove surface hydroxyl groups and heating at 100.degree.-150.degree. C. for 1/2 to 3 hours; (b) contacting said treated inert inorganic support with a hydrocarbon soluble magnesium compound; (c) contacting said product of said step (b) with a modifying compound selected from the group consisting of silicon halides, boron halides, aluminum halides, hexaalkyldisilazanes and mixtures thereof; (d) contacting said product of said step (c) with a vanadium compound having the structural formula V(O).sub.s X.sup.1.sub.4-s, where X.sup.1 is halogen; and s is 0 or 1; a first titanium-containing compound having the structural formula TiX.sup.3.sub.p (OR.sup.3).sub.q, where X.sup.3 is halogen; R.sup.3 is hydrocarbyl; p is an integer of 1 to 4; and q is 0 or an integer of 1 to 3, with the proviso that the sum of p and q is 4 and, optionally, a second titanium-containing compound of the formula Ti(OR.sup.2).sub.n X.sup.2.sub.m, where R.sup.2 is hydrocarbyl; X.sup.2 is halogen; n is an integer of 1 to 4; and m is 0 or an integer of 1 to 3 with the proviso that the sum of n and m is 4; and with the further proviso that if two titanium-containing compounds are used said first and said second titanium-containing compounds are not identical. ### Claim 16 (depends on 15) The process of claim 15 wherein the catalyst is obtained by an alkylaluminum or alkylaluminum halide and an optional silane cocatalyst of the formula R'.sub.a (OR").sub.4-a Si where R' and R" are hydrocarbyl groups are present with the titanium-containing catalyst component. ### Claim 17 (depends on 6) The process of claim 6 wherein the titanium-containing catalyst component is obtained by (a) treating an inert inorganic support to a temperature of 100.degree. C. to 150.degree. C. for 1/2 to 3 hours to remove surface hydroxyl groups; (b) contacting the treated inert inorganic compound with a hydrocarbon soluble magnesium compound; (c) contacting the product of said step (b) with a modifying compound selected from the group consisting of silicon halides, boron halides, aluminum halides, alkyl silicon halides, hexaalkyldisilazanes and mixtures thereof; and (d) contacting the product of said step (c) with a vanadium compound having the structural formula V(O.sub.2)X.sup.1.sub.4-s, is halogen and s is 0 or 1; a first titanium-containing compound having the structural formula TiX.sup.3.sub.p (OR.sup.3).sub.q, where X.sup.3 is halogen, R.sup.3 is hydrocarbyl, p is an integer of 1 to 4, and q is 0 or an integer of 1 to 3, with the proviso that the sum of p and q is 4 and, optionally, a second titanium-containing compound of the formula Ti(OR.sup.2).sub.n X.sup.2.sub.m, where R.sup.2 is hydrocarbyl, X.sup.2 is halogen, n is an integer of 1 to 4, and m is 0 or an integer of 1 to 3 with the proviso that the sum of n and m is 4; and with the further proviso that if two titanium-containing compounds are used said first and said second titanium-containing compounds are not identical. ### Claim 18 (depends on 17) The process of claim 17 wherein an alkylaluminum or alkylaluminum halide and an optional silane cocatalyst of the formula R'.sub.a (OR").sub.4-a Si where R' and R" are hydrocarbyl groups are present with the titanium-containing catalyst component. ### Claim 19 (depends on 1) A modified polypropylene having improved paint adhesion and reduced hexane extractables produced by the process of claim 1 containing from 15 to 30 weight percent ethylene and having a value for Q in the range 0.65 to 1.0 where Q is determined using integrated areas of the .sup.13 C NMR spectrum of the copolymer in accordance with the equation: ##EQU4## where A=1.167R.sub.1 +0.75R.sub.2 +1.5R.sub.3 +1.5R.sub.4 +1.167R.sub.8 B=0.667R.sub.1 +0.5R.sub.2 +R.sub.5 +R.sub.6 +R.sub.7 +0.667R.sub.8 and R.sub.1 through R.sub.8 have the following peak assignments ______________________________________ R.sub.1 37.9 PPM R.sub.2 37.5 PPM R.sub.3 33.2 PPM R.sub.4 31.2-30.9 PPM R.sub.5 30.4 PPM R.sub.6 30.0 PPM R.sub.7 27.4 PPM R.sub.8 24.9 PPM ______________________________________ ### Claim 20 (depends on 19) The modified polypropylene of claim 19 wherein Q is in the range 0.75 to 0.98.