講者：Dr. Andy H. Tsou
演講題目：Bimodal Comb Block Polyolefins from Serial Reactors
演講時間：10/23（五）15:30~17:20
演講地點：博雅館 201
主持人：王大銘教授
Bio- Andy H. Tsou
Presently, a Senior Research Associate in Global Chemical Research of ExxonMobil Chemical Company in Baytown, Texas. Andy received his PhD in Chemical Engineering from Purdue University in 1987. He spent 10 years at Eastman Kodak prior to joining ExxonMobil Chemical Company in Baytown, Texas. For his work in polymer microscopy and rheology, Andy received Frank Giblin Memorial Award in Polymer Analysis from Society of Plastic Engineers in 2000. Subsequently, Andy was involved the development and commercialization of metallocene propylene elastomers, Vistamaxx™, in 2004. For his work in elastomer morphology quantification and in elastomer product development, Andy received the Sparks-Thomas award in 2004 from ACS Rubber Division recognizing outstanding scientific contributions and innovations in elastomers by younger scientists. From 2002 to 2006, Andy led the efforts in developing and commercializing Exxcore™ DVA (Dynamic Vulcanized Alloy) material. For his innovation and commercialization of Exxcore DVA in 2006, Andy was featured in Essential 2 campaign, cover page article, from American Chemistry Council in 2007. In 2015, the sustained collaborative research activities over the past 15 years between Andy and Prof. Ben Hsiao of Stony Brook University on developing frontier synchrotron X-ray scattering techniques and applications of these techniques to assist the development and commercialization of new polyolefins have led to their receiving of 2015 ACS PMSE Cooperative Research Award.
From 2007 to 2011, Andy has been responsible in managing the Structure and Performance of Organic Materials section as a Section Head in Corporate Strategic Research of ExxonMobil Research and Engineering Company in Clinton, New Jersey, while conducting research in areas of polymer science and lubrication science. Starting in 2011, Andy has transitioned back to research and was moved back to ExxonMobil Chemical Company in January, 2014. Andy has more than 90 US patents and patent applications and more than 120 external publications. He has received two Best Paper awards and one Best Symposium award and is presently on the editorial board of Rubber Chemistry and Technology and on the technical program committee of ACS PMSE (Polymer Materials Science and Engineering) division.
Bimodal Comb Block Polyolefins from Serial Reactors
Andy H. Tsou, Carlos R. Lopez-Barron, Peijun Jiang, and Donna J. Crowther
Global Chemical Research, ExxonMobil Chemical Company, Baytown, Texas, USA
By employing solution serial reactors along with judicious choices of organometallic catalysts, bimodal comb block copolyolefins can be produced with bimodalities in molecular weight, in branching, and in composition distributions. A low molecular weight (MW) vinyl terminated polyolefin prepared in the first reactor along with its catalyst and unreacted olefin monomer was fed directly into the second reactor without purification and catalyst termination. A second olefin monomer and a second catalyst capable of incorporating macromers and of producing high MW were then added in the second reactor leading to the synthesis of bimodal comb block polyolefins. These comb block copolyolefins contain low MW linear polyolefins of mixed compositions and high MW comb branched polyolefins of a constant composition.
Various bimodal PE-sb-aPP, or polyethylene-(side block)-atactic polypropylene, was thus prepared with propylene being the first-reactor monomer and ethylene being the second-reactor monomer with varying aPP comb arm MW, backbone MW, and comb arm number. Their bimodalities were confirmed by GPC-4D (Gel Permeation Chromatography-4 Detectors) and by extraction C13 NMR (Carbon 13 Nuclear Magnetic Resonance). The presence of these low MW linear polypropylene and poly(propylene-r-ethylene) may prevent the micelle formation of the high MW comb block PE-sb-aPP as evident by the devoid of micelles, as examined by bimodal AFM (atomic force microscopy), when the bimodal PE-sb-aPP was added into HDPE (high density polyethylene), iPP (isotactic polypropylene), and blends of HDPE and iPP. Without the micelle formation, the high MW PE-sb-aPP can be intimately entangled with HDPE and with iPP delivering extensional flow hardening, as measured by SER (Sentmanat Extensional Rheometer) rheometer, when the bimodal PE-sb-aPP was added at 5% or less.
In addition to enhancing processabiity of PE, iPP, and PE/iPP blends, it was found that this bimodal PE-sb-aPP can compatibilize the immiscible blends of HDPE and iPP. As revealed by SEM (Scanning Electron Microscopy), domain sizes are significantly reduced in blends with HDPE dispersion, iPP dispersion, and HDPE and iPP co-continuous morphologies. Although the lack-of-material-contrast preventing the detection of PE-sb-aPP at the PE/PP interfaces, diffused interfaces were apparent in bimodal AFM micrographs at high magnifications of all PE and PP blends when the bimodal PE-sb-aPP was added. Both the domain size reductions and the diffused interfaces suggest compatibilized blends in the presence of PE-sb-aPP. The importance of this low MW linear mixed-composition polyolefin in bimodal comb block polyolefin to prevent the micelle formation of the comb block needs to be verified through the synthesis of a comparable example of a pure PE-sb-aPP using a single reactor in two steps with purification and separation after each step.[:en]Speaker：Dr. Andy H. Tsou
Topic：Bimodal Comb Block Polyolefins from Serial Reactors
Date：10/23（五）15:30~17:20
Location：博雅館 201
Host ： Prof. Da-Ming Wang
Bio- Andy H. Tsou
Presently, a Senior Research Associate in Global Chemical Research of ExxonMobil Chemical Company in Baytown, Texas. Andy received his PhD in Chemical Engineering from Purdue University in 1987. He spent 10 years at Eastman Kodak prior to joining ExxonMobil Chemical Company in Baytown, Texas. For his work in polymer microscopy and rheology, Andy received Frank Giblin Memorial Award in Polymer Analysis from Society of Plastic Engineers in 2000. Subsequently, Andy was involved the development and commercialization of metallocene propylene elastomers, Vistamaxx™, in 2004. For his work in elastomer morphology quantification and in elastomer product development, Andy received the Sparks-Thomas award in 2004 from ACS Rubber Division recognizing outstanding scientific contributions and innovations in elastomers by younger scientists. From 2002 to 2006, Andy led the efforts in developing and commercializing Exxcore™ DVA (Dynamic Vulcanized Alloy) material. For his innovation and commercialization of Exxcore DVA in 2006, Andy was featured in Essential 2 campaign, cover page article, from American Chemistry Council in 2007. In 2015, the sustained collaborative research activities over the past 15 years between Andy and Prof. Ben Hsiao of Stony Brook University on developing frontier synchrotron X-ray scattering techniques and applications of these techniques to assist the development and commercialization of new polyolefins have led to their receiving of 2015 ACS PMSE Cooperative Research Award.
From 2007 to 2011, Andy has been responsible in managing the Structure and Performance of Organic Materials section as a Section Head in Corporate Strategic Research of ExxonMobil Research and Engineering Company in Clinton, New Jersey, while conducting research in areas of polymer science and lubrication science. Starting in 2011, Andy has transitioned back to research and was moved back to ExxonMobil Chemical Company in January, 2014. Andy has more than 90 US patents and patent applications and more than 120 external publications. He has received two Best Paper awards and one Best Symposium award and is presently on the editorial board of Rubber Chemistry and Technology and on the technical program committee of ACS PMSE (Polymer Materials Science and Engineering) division.
Bimodal Comb Block Polyolefins from Serial Reactors
Andy H. Tsou, Carlos R. Lopez-Barron, Peijun Jiang, and Donna J. Crowther
Global Chemical Research, ExxonMobil Chemical Company, Baytown, Texas, USA
By employing solution serial reactors along with judicious choices of organometallic catalysts, bimodal comb block copolyolefins can be produced with bimodalities in molecular weight, in branching, and in composition distributions. A low molecular weight (MW) vinyl terminated polyolefin prepared in the first reactor along with its catalyst and unreacted olefin monomer was fed directly into the second reactor without purification and catalyst termination. A second olefin monomer and a second catalyst capable of incorporating macromers and of producing high MW were then added in the second reactor leading to the synthesis of bimodal comb block polyolefins. These comb block copolyolefins contain low MW linear polyolefins of mixed compositions and high MW comb branched polyolefins of a constant composition.
Various bimodal PE-sb-aPP, or polyethylene-(side block)-atactic polypropylene, was thus prepared with propylene being the first-reactor monomer and ethylene being the second-reactor monomer with varying aPP comb arm MW, backbone MW, and comb arm number. Their bimodalities were confirmed by GPC-4D (Gel Permeation Chromatography-4 Detectors) and by extraction C13 NMR (Carbon 13 Nuclear Magnetic Resonance). The presence of these low MW linear polypropylene and poly(propylene-r-ethylene) may prevent the micelle formation of the high MW comb block PE-sb-aPP as evident by the devoid of micelles, as examined by bimodal AFM (atomic force microscopy), when the bimodal PE-sb-aPP was added into HDPE (high density polyethylene), iPP (isotactic polypropylene), and blends of HDPE and iPP. Without the micelle formation, the high MW PE-sb-aPP can be intimately entangled with HDPE and with iPP delivering extensional flow hardening, as measured by SER (Sentmanat Extensional Rheometer) rheometer, when the bimodal PE-sb-aPP was added at 5% or less.
In addition to enhancing processabiity of PE, iPP, and PE/iPP blends, it was found that this bimodal PE-sb-aPP can compatibilize the immiscible blends of HDPE and iPP. As revealed by SEM (Scanning Electron Microscopy), domain sizes are significantly reduced in blends with HDPE dispersion, iPP dispersion, and HDPE and iPP co-continuous morphologies. Although the lack-of-material-contrast preventing the detection of PE-sb-aPP at the PE/PP interfaces, diffused interfaces were apparent in bimodal AFM micrographs at high magnifications of all PE and PP blends when the bimodal PE-sb-aPP was added. Both the domain size reductions and the diffused interfaces suggest compatibilized blends in the presence of PE-sb-aPP. The importance of this low MW linear mixed-composition polyolefin in bimodal comb block polyolefin to prevent the micelle formation of the comb block needs to be verified through the synthesis of a comparable example of a pure PE-sb-aPP using a single reactor in two steps with purification and separation after each step.