Dow Global Technolgoies LLC

Dow Brasil Sudeste Industrial Ltda

Cornelis J F Hosman

Otto J Berbee

Joaquin Flores

Nhi T Y Dang

Nhi Dang

Sergio E Goncalves

Sarat Munjal

Stefan Hinrichs

Michael E Bishop

Luiz Rodriguez

A high pressure polymerization, as described herein, to form an ethylene-based polymer, comprising the following steps: polymerizing a reaction mixture comprising ethylene, using a reactor system comprising at least three ethylene-based feed streams and a reactor configuration that comprises at least four reaction zones, and at least one of the following a) through c), is met: (a) up to 100 wt % of the ethylene stream to the first zone comes from a high pressure recycle, and/or up to 100 wt % of the last ethylene stream to a zone comes from the output from a Primary compressor system; and/or (b) up to 100 wt % of the ethylene stream to first zone comes from the output from a Primary compressor system, and/or up to 100 wt % of the last ethylene stream to a zone comes from a high pressure recycle; and/or (c) the ethylene stream to the first zone, and/or the last ethylene stream to a zone, each comprises a controlled composition; and wherein each ethylene stream to a zone receives an output from two or more cylinders of the last compressor stage of a Hyper compressor system.

High pressure, free radical polymerizations to produce ethylene-based polymers

A process to form an ethylene-based polymer in a reactor system, said process comprising at least the following steps: a) injecting a first initiator mixture into the tubular reactor at location L along the reactor, b) injecting a compressed make-up CTA system at the location L, at a distance (L&#x2212;L) from 145*Dto 1000*D, upstream from L, and wherein D=the inner diameter of the pre-heater in meter (m); and wherein Lis located in the preheater, and c) optionally, injecting one or more additional compressed make-up CTA system(s) into the preheater, at one or more location: LL, L(2&#x2264;i and 2&#x2264;n), upstream from L, and each location is, independently, at a distance from 145*Dto 1000*D, and wherein n equals the total number of injection locations of the make-up CTA system(s) injected into the preheater, upstream from L, and wherein (L&#x2212;L) is less than each (L&#x2212;L), (L&#x2212;L), (L&#x2212;L); and d) polymerizing a reaction mixture comprising at least ethylene, the first initiator mixture, and the compressed make-up CTA system of step b), and wherein the process has a log coefficient of variation (log(CoV)), at L, that meets the relationships described herein.

A process to form an ethylene-based polymer, as described herein, in a tubular reactor system comprising at least three ethylene-based feeds, and at least four reaction zones, and where the weight ratio of 'the ethylene-based feed to the second zone (EBF2)' to 'the ethylene-based feed to the first zone (EBF1),' is from 0.50 to 1.10; and the weight ratio of &#x201c;the ethylene-based feed to the third zone (EBF3)&#x201d; to &#x201c;the ethylene-based feed to the first zone (EBF1),&#x201d; is from 0.40 to 2.50; in each zone, the polymerization takes place at a start temperature&#x2265;135&#xb0; C.; and (a) for three or more ethylene based feeds, the peak temperatures in the first and the second zones, are each from 200&#xb0; C. to 250&#xb0; C.; and/or (b) for four or more ethylene based feeds, the peak temperatures in the first, the second and the third zones, are each from 200&#xb0; C. to 250&#xb0; C.; and the differential in peak temperatures of the first three zones (TP1, TP2, TP3) meets at least one relationship described herein.

Ethylene-based polymers formed by high pressure free radical polymerizations

A process to form an ethylene-based polymer comprising polymerizing a mixture comprising ethylene, in the presence of a free-radical initiator, and in a tubular reactor system comprising at least two ethylene-based feed streams, and a reactor configuration that comprises at least three reaction zones; and the inlet pressure of the first zone is &#x3c;3200 Bar; and the ethylene conversion &#x3e;28%, and an m value from 20 mole % to 70 mole %, where m=mol % of ethylene-based feed stream to the first zone, based on total moles of ethylene-based feed streams fed to the reactor configuration; and the ratio (Q) of a 'MWDB of a broad polymer polymerized, to a 'MWDN of a narrow polymer polymerized, is as follows: {(T)*(&#x2212;2.3&#xd7;log(m)+7)}&#x2264;Q&#x2264;{(T)*(&#x2212;13.0&#xd7;log(m)+29.8)}; at the same melt index; and &#x201c;T' is the &#x201c;chain transfer activity ratio' as described herein.

A process is provided to form an ethylene-based polymer, in the presence of at least one free-radical, said process comprises at least the following: polymerizing a mixture comprising ethylene, in a reactor configuration comprising at least three reaction zones, and comprising two ethylene feed streams, and wherein the ratio (R), in percent, of the 'LCB content of the first 40 wt % of the total polymer formed' to 'the total LCB content in the final polymer' is &#x2264;22.5%; and wherein the amount of ethylene, and optionally one or more comonomers, and optionally one or more CTAs, fed to the first reaction zone, is from 40 mole % to 80 mole %, based on the total moles of ethylene, and optionally one or more comonomers, and optionally one or more CTAs, fed to the polymerization.

High pressure free radical polymerizations

Ethylene-based polymer, LDPE, is made in a high pressure polymerization process to comprising at least the step of polymerizing a reaction mixture comprising ethylene, using a reactor configuration comprising (A) at least two reaction zones, a first reaction zone (reaction zone 1) and an i reaction zone (reaction zone i where i&#x3e;2), (B) at least two ethylene feed streams, each feed stream comprising a percentage of the total make-up ethylene fed to the polymerization process, in which a first ethylene feed stream is sent to reaction zone 1 and a second ethylene feed stream is sent to reaction zone i, and (C) a control system to control the percentage of the total make-up ethylene in the ethylene feed stream sent to reaction zone 1 and the percentage of the total make-up ethylene in the ethylene feed stream sent to reaction zone i.

High pressure free radical polymerization process with flexible control of molecular weight distribution

A process to form an ethylene-based polymer, in the presence of at least one free-radical, said process comprises at least the following: polymerizing a mixture comprising ethylene in a reactor configuration comprising at least four reaction zones, and comprising at least three ethylene feed streams; and wherein the ratio of (R), in percent, of the LCB content of the 'first 40 wt % of the total polymer formed' to the 'total LCB content in the final polymer' is &#x2264;29%; and wherein the amount of ethylene, and optionally one or more comonomers, and optionally one or more CTAs, fed to the first reaction zone, is from 20 mole % to 70 mole %, based on the total moles of ethylene, and optionally one or more comonomers, and optionally one or more CTAs, fed to the polymerization.

A process to form an ethylene-based polymer, said process comprising at least the following: polymerizing a mixture comprising ethylene, in the presence of at least one free-radical initiator, and in a reactor configuration comprising at least three reaction zones and at least two ethylene feed streams; and wherein the inlet pressure of the first reaction zone is less than, or equal to, 3200 Bar; and wherein the amount of ethylene, and optionally one or more comonomers, and optionally one or more CTAs, fed to the first reaction zone is from 40 mole % to 80 mole %, based on the total moles of ethylene, and optionally one or more comonomers, and optionally one or more CTAs, fed to the polymerization; and wherein the average polymerization temperature of the first 40 wt % polymer formed (APT) (based on the total amount of polymer formed) is less than, or equal to, 200&#xb0; C.

The invention provides a process to prepare an ethylene-based polymer, said process comprising polymerizing ethylene in the presence of at least one initiator system selected from the following: a) class 1 initiator system, b) class 2 initiator system, c) class 3 initiator system, or d) a combination thereof; and at a inlet pressure (P) greater than, or equal to, 1000 Bar (100 MPa); and in a reactor system comprising at least one hyper compressor and a reactor configuration comprising at least one reactor, which comprises at least one reaction zone; and wherein the inlet pressure (P) is reduced by at least 200 Bar, as compared to a similar polymerization, in the same reactor system, except it is operated at a higher inlet pressure (P), and at a different hyper compressor throughput, and at a different maximum temperature for at least one reaction zone, and optionally, at a different amount of CTA system fed to the reactor configuration; and wherein, for the process, the 'Ratio of total reactor consumption of the highest temperature class initiator system(s) (Y)' meets the following Equation D: 0.95*x^((P&#x2212;P)/10 MPa)&#x3c;Y&#x3c;1.04*z^((P&#x2212;P)/10 MPa) (Eqn. D), wherein x is greater than, or equal to, 0.97; and wherein z is less than, or equal to, 1.03. The invention also provides a process to prepare an ethylene-based polymer, said process comprising polymerizing ethylene in the presence of at least one initiator system selected from the following: a) a class 1 initiator system, b) a class 2 initiator system, c) a class 3 initiator system, or d) a combination thereof; and at an inlet pressure (P) greater than, or equal to, 1000 Bar (100 MPa); and in a reactor system comprising a reactor configuration comprising at least one reactor, which comprises at least one reaction zone; and wherein the inlet pressure (P) is reduced by at least 200 Bar, as compared to a similar polymerization, in the same reactor configuration, except it is operated at a higher inlet pressure (P), and at a different maximum temperature for at least one reaction zone, and optionally, at a different amount of CTA system fed to the reactor configuration; and wherein, for the process, the 'Ratio of total reactor consumption of the highest temperature class initiator system(s) (Y)' meets the following Equation D: 0.95*x^((P&#x2212;P)/10 MPa)&#x3c;Y&#x3c;1.04*z^((P&#x2212;P)/10 MPa) (Eqn. D), wherein x is greater than, or equal to, 0.97; and wherein z is less than, or equal to, 1.03.

Growing community of inventors

Ijzendijke, Netherlands

Cornelis J F Hosman