公开(公告)号：US20230056312A1

公开(公告)日：2023-02-23

申请号：US17791389

申请日：2021-01-07

Applicant: ExxonMobil Chemical Patents Inc.

Inventor： Xiaodan ZHANG ,  Christopher G. BAUCH ,  Todd S. EDWARDS ,  Mark S. CHAHL ,  Blu E. ENGLEHORN ,  Khoa TO ,  Steven L. LAMBERT

IPC: C08F110/06 ,  C08L23/14

Abstract: Provided are methods for producing bimodal polyolefins comprising the steps of contacting α-olefin monomers with a catalyst in slurry polymerization conditions in the presence of zero to minimum hydrogen to produce a high molecular weight polyolefin and contacting additional α-olefin monomers in gas phase polymerization conditions and the high molecular weight polyolefin and the catalyst to produce bimodal polyolefin having high stiffness and broad molecular weight distribution. An additional step of polymerizing the bimodal polyolefin with a comonomer in a second gas phase can provide a bimodal impact copolymer having high stiffness and broad molecular weight distribution. Among the advantages of the present methods, bimodal polyolefins can be produced in a continuous process between a slurry polymerization reactor and a gas phase polymerization reactor without a venting step in between and with minimal hydrogen in the slurry polymerization reactor.

公开(公告)号：US20230235105A1

公开(公告)日：2023-07-27

申请号：US18001438

申请日：2021-07-12

Applicant: EXXONMOBIL CHEMICAL PATENTS INC.

Inventor： Todd S. EDWARDS ,  Christopher G. BAUCH ,  Ranadip GANGULY ,  Xiaodan ZHANG

IPC: C08F210/06 ,  C08F2/18 ,  C08L23/12

CPC classification number: C08F210/06 ,  C08F2/18 ,  C08L23/12

Abstract: Polypropylenes and impact copolymers with low organic volatiles. The impact copolymers comprising a polypropylene and within a range from 5 wt% to 40 wt% of an ethylene-propylene copolymer or rubber, by weight of the impact copolymer; wherein the polypropylene has a melt flow rate within a range from 100 g/10 min to 400 g/10 min, and the impact copolymer has a melt flow rate within a range from 15 g/10 min to 150 g/10 min; and wherein there are less than 1000 µg of oligomer per gram of impact copolymer. The polymers may be made by combining olefins with the reaction product of a solid magnesium compound and a halogen-containing titanium compound with at least one phthalic acid ester compound and at least one diether compound as internal electron donors.

公开(公告)号：US20230077569A1

公开(公告)日：2023-03-16

申请号：US17759598

申请日：2021-02-12

Applicant: ExxonMobil Chemical Patents Inc.

Inventor： George J. PEHLERT ,  Ranadip GANGULY ,  Christopher G. BAUCH ,  Blu E. ENGLEHORN ,  Xiaodan ZHANG ,  Mark S. CHAHL ,  Kevin W. LAWSON ,  Xuejia YAN

IPC: C08F210/06 ,  C08L23/12

Abstract: Processes for forming a polypropylene composition are provided herein comprising the steps of making a first propylene-based copolymer having a molecular weight distribution between 3 to 8.5, and making a second propylene-based polymer in the presence of the first propylene-based polymer to produce the polypropylene composition having a high molecular weight tail in the amount of between 1.0 wt. % and 10.0 wt. %. The polypropylene compositions produced have a broad molecular weight distribution and high molecular weight tail to provide improved stiffness while retaining toughness.

公开(公告)号：US20220332864A1

公开(公告)日：2022-10-20

申请号：US17640172

申请日：2020-08-14

Applicant: EXXONMOBIL CHEMICAL PATENTS INC.

Inventor： Xiaodan ZHANG ,  Christopher G. BAUCH ,  Lubin LUO ,  Jeffrey L. BRINEN ,  George J. PEHLERT ,  Todd S. EDWARDS ,  Sung A. KIM

IPC: C08F210/06

Abstract: Provided herein are methods of polymerizing α-olefin monomer with a catalyst and hydrogen in a slurry to produce low molecular weight polyolefins. Hydrogen is vented from the low molecular weight polyolefins and then the low molecular weight polyolefins are further polymerized in a gas phase to produce a polyolefin having a molecular weight distribution of between 4.0 and 30 and a flexural modulus between 1500 mPa and 2500 mPa.