Free-radical polymerization engineering—III. Modelling homogeneous polymerization of ethylene: mathematical model and new method for obtaining molecular-weight distribution
Identifieur interne : 001111 ( Istex/Corpus ); précédent : 001110; suivant : 001112Free-radical polymerization engineering—III. Modelling homogeneous polymerization of ethylene: mathematical model and new method for obtaining molecular-weight distribution
Auteurs : Pascal Lorenzini ; Michel Pons ; Jacques VillermauxSource :
- Chemical Engineering Science [ 0009-2509 ] ; 1992.
English descriptors
- KwdEn :
- Activation energies, Active center, Autoclave reactors, Blavier, Carbon atoms, Chain transfer, Chem, Coefficient, Computer model, Dead fragment, Dead macromolecules, Dead polymer, Different processes, Dimensionless parameter, Distribution exhibits, Double bond, Double bonds, Experimental data, Experimental distribution, Free radicals, Heuristic method, Initiator, Initiator concentration, Initiator feed stream, Intramolecular transfer, Kinetic mechanism, Kinetic model, Kinetic parameters, Laguerre polynomials, Large number, Long branches, Macromolecule, Mathematical model, Micromixing time, Model equations, Molecular mass, Molecular structure, Molecular weight, Mother distribution, Negative parts, Next paper, Number distribution, Overall concentration, Pascal, Pascal lorenzini, Permeation chromatography, Polyethylene, Polymer, Polymer quality, Polymerization, Polymerization degree, Polymerization degrees, Present model, Present paper, Qssa, Rate coefficients, Reactor, Reactor axis, Real solutions, Remarkable property, Scission, Secondary carbon atoms, Secondary radicals, Several kinds, Short branches, Statistical moments, Structural characters, Tendency model, Total concentration, Transfer agent, Villermaux, Weight distribution.
- Teeft :
- Activation energies, Active center, Autoclave reactors, Blavier, Carbon atoms, Chain transfer, Chem, Coefficient, Computer model, Dead fragment, Dead macromolecules, Dead polymer, Different processes, Dimensionless parameter, Distribution exhibits, Double bond, Double bonds, Experimental data, Experimental distribution, Free radicals, Heuristic method, Initiator, Initiator concentration, Initiator feed stream, Intramolecular transfer, Kinetic mechanism, Kinetic model, Kinetic parameters, Laguerre polynomials, Large number, Long branches, Macromolecule, Mathematical model, Micromixing time, Model equations, Molecular mass, Molecular structure, Molecular weight, Mother distribution, Negative parts, Next paper, Number distribution, Overall concentration, Pascal, Pascal lorenzini, Permeation chromatography, Polyethylene, Polymer, Polymer quality, Polymerization, Polymerization degree, Polymerization degrees, Present model, Present paper, Qssa, Rate coefficients, Reactor, Reactor axis, Real solutions, Remarkable property, Scission, Secondary carbon atoms, Secondary radicals, Several kinds, Short branches, Statistical moments, Structural characters, Tendency model, Total concentration, Transfer agent, Villermaux, Weight distribution.
Abstract
Abstract: A specific approach based on a “tendecy model”, intermediate between the “black-box” and the “detailed analytical” models, has been developed. It makes it possible to predict both the amount of polymer produced in the autoclave process, and the quality of the polymer, expressed in terms of molecular structure: molecular-weight distribution (MWD), average molecular weights, long- and short-branching indices, double-bond indices. The prediction of conversion requires an appropriate representation of partial segregation of the initiator feedstream. The prediction of quality is based on a kinetic model taking into account the most important mechanism recognized for this reaction. Several kinds of free radicals are involved to which the quasi-steady-state assumption is applied. Processes giving rise to new chains are identified and the statistical moments for the corresponding distributions are derived. The moments of the overall dead polymer population are finally derived,thanks to a mixing theorem. In spite of the difficulties caused by transfer to polymer and scission of free radicals, equations for the moments are obtained in a closed form and this constituents a remarkable property of the present model. An expression for the MWD can then be obtained from its statistical moments by an original method based on the deformation of a known distribution.
Url:
DOI: 10.1016/0009-2509(92)85146-3
Links to Exploration step
ISTEX:F2114A91EA51074353F30570A1CF47D9A10C023FLe document en format XML
<record><TEI wicri:istexFullTextTei="biblStruct"><teiHeader><fileDesc><titleStmt><title xml:lang="en">Free-radical polymerization engineering—III. Modelling homogeneous polymerization of ethylene: mathematical model and new method for obtaining molecular-weight distribution</title><author><name sortKey="Lorenzini, Pascal" sort="Lorenzini, Pascal" uniqKey="Lorenzini P" first="Pascal" last="Lorenzini">Pascal Lorenzini</name><affiliation><mods:affiliation>Laboratoire des Science du Génie Chimique, CNRS—ENSIC—Institut National Polytechnique de Lorraine, 1 rue Grandville, BP 451, 54001 Nancy Cedex, France</mods:affiliation></affiliation></author><author><name sortKey="Pons, Michel" sort="Pons, Michel" uniqKey="Pons M" first="Michel" last="Pons">Michel Pons</name><affiliation><mods:affiliation>Laboratoire des Science du Génie Chimique, CNRS—ENSIC—Institut National Polytechnique de Lorraine, 1 rue Grandville, BP 451, 54001 Nancy Cedex, France</mods:affiliation></affiliation></author><author><name sortKey="Villermaux, Jacques" sort="Villermaux, Jacques" uniqKey="Villermaux J" first="Jacques" last="Villermaux">Jacques Villermaux</name><affiliation><mods:affiliation>Laboratoire des Science du Génie Chimique, CNRS—ENSIC—Institut National Polytechnique de Lorraine, 1 rue Grandville, BP 451, 54001 Nancy Cedex, France</mods:affiliation></affiliation></author></titleStmt><publicationStmt><idno type="wicri:source">ISTEX</idno><idno type="RBID">ISTEX:F2114A91EA51074353F30570A1CF47D9A10C023F</idno><date when="1992" year="1992">1992</date><idno type="doi">10.1016/0009-2509(92)85146-3</idno><idno type="url">https://api.istex.fr/document/F2114A91EA51074353F30570A1CF47D9A10C023F/fulltext/pdf</idno><idno type="wicri:Area/Istex/Corpus">001111</idno><idno type="wicri:explorRef" wicri:stream="Istex" wicri:step="Corpus" wicri:corpus="ISTEX">001111</idno></publicationStmt><sourceDesc><biblStruct><analytic><title level="a" type="main" xml:lang="en">Free-radical polymerization engineering—III. Modelling homogeneous polymerization of ethylene: mathematical model and new method for obtaining molecular-weight distribution</title><author><name sortKey="Lorenzini, Pascal" sort="Lorenzini, Pascal" uniqKey="Lorenzini P" first="Pascal" last="Lorenzini">Pascal Lorenzini</name><affiliation><mods:affiliation>Laboratoire des Science du Génie Chimique, CNRS—ENSIC—Institut National Polytechnique de Lorraine, 1 rue Grandville, BP 451, 54001 Nancy Cedex, France</mods:affiliation></affiliation></author><author><name sortKey="Pons, Michel" sort="Pons, Michel" uniqKey="Pons M" first="Michel" last="Pons">Michel Pons</name><affiliation><mods:affiliation>Laboratoire des Science du Génie Chimique, CNRS—ENSIC—Institut National Polytechnique de Lorraine, 1 rue Grandville, BP 451, 54001 Nancy Cedex, France</mods:affiliation></affiliation></author><author><name sortKey="Villermaux, Jacques" sort="Villermaux, Jacques" uniqKey="Villermaux J" first="Jacques" last="Villermaux">Jacques Villermaux</name><affiliation><mods:affiliation>Laboratoire des Science du Génie Chimique, CNRS—ENSIC—Institut National Polytechnique de Lorraine, 1 rue Grandville, BP 451, 54001 Nancy Cedex, France</mods:affiliation></affiliation></author></analytic><monogr></monogr><series><title level="j">Chemical Engineering Science</title><title level="j" type="abbrev">CES</title><idno type="ISSN">0009-2509</idno><imprint><publisher>ELSEVIER</publisher><date type="published" when="1992">1992</date><biblScope unit="volume">47</biblScope><biblScope unit="issue">15–16</biblScope><biblScope unit="page" from="3969">3969</biblScope><biblScope unit="page" to="3980">3980</biblScope></imprint><idno type="ISSN">0009-2509</idno></series></biblStruct></sourceDesc><seriesStmt><idno type="ISSN">0009-2509</idno></seriesStmt></fileDesc><profileDesc><textClass><keywords scheme="KwdEn" xml:lang="en"><term>Activation energies</term><term>Active center</term><term>Autoclave reactors</term><term>Blavier</term><term>Carbon atoms</term><term>Chain transfer</term><term>Chem</term><term>Coefficient</term><term>Computer model</term><term>Dead fragment</term><term>Dead macromolecules</term><term>Dead polymer</term><term>Different processes</term><term>Dimensionless parameter</term><term>Distribution exhibits</term><term>Double bond</term><term>Double bonds</term><term>Experimental data</term><term>Experimental distribution</term><term>Free radicals</term><term>Heuristic method</term><term>Initiator</term><term>Initiator concentration</term><term>Initiator feed stream</term><term>Intramolecular transfer</term><term>Kinetic mechanism</term><term>Kinetic model</term><term>Kinetic parameters</term><term>Laguerre polynomials</term><term>Large number</term><term>Long branches</term><term>Macromolecule</term><term>Mathematical model</term><term>Micromixing time</term><term>Model equations</term><term>Molecular mass</term><term>Molecular structure</term><term>Molecular weight</term><term>Mother distribution</term><term>Negative parts</term><term>Next paper</term><term>Number distribution</term><term>Overall concentration</term><term>Pascal</term><term>Pascal lorenzini</term><term>Permeation chromatography</term><term>Polyethylene</term><term>Polymer</term><term>Polymer quality</term><term>Polymerization</term><term>Polymerization degree</term><term>Polymerization degrees</term><term>Present model</term><term>Present paper</term><term>Qssa</term><term>Rate coefficients</term><term>Reactor</term><term>Reactor axis</term><term>Real solutions</term><term>Remarkable property</term><term>Scission</term><term>Secondary carbon atoms</term><term>Secondary radicals</term><term>Several kinds</term><term>Short branches</term><term>Statistical moments</term><term>Structural characters</term><term>Tendency model</term><term>Total concentration</term><term>Transfer agent</term><term>Villermaux</term><term>Weight distribution</term></keywords><keywords scheme="Teeft" xml:lang="en"><term>Activation energies</term><term>Active center</term><term>Autoclave reactors</term><term>Blavier</term><term>Carbon atoms</term><term>Chain transfer</term><term>Chem</term><term>Coefficient</term><term>Computer model</term><term>Dead fragment</term><term>Dead macromolecules</term><term>Dead polymer</term><term>Different processes</term><term>Dimensionless parameter</term><term>Distribution exhibits</term><term>Double bond</term><term>Double bonds</term><term>Experimental data</term><term>Experimental distribution</term><term>Free radicals</term><term>Heuristic method</term><term>Initiator</term><term>Initiator concentration</term><term>Initiator feed stream</term><term>Intramolecular transfer</term><term>Kinetic mechanism</term><term>Kinetic model</term><term>Kinetic parameters</term><term>Laguerre polynomials</term><term>Large number</term><term>Long branches</term><term>Macromolecule</term><term>Mathematical model</term><term>Micromixing time</term><term>Model equations</term><term>Molecular mass</term><term>Molecular structure</term><term>Molecular weight</term><term>Mother distribution</term><term>Negative parts</term><term>Next paper</term><term>Number distribution</term><term>Overall concentration</term><term>Pascal</term><term>Pascal lorenzini</term><term>Permeation chromatography</term><term>Polyethylene</term><term>Polymer</term><term>Polymer quality</term><term>Polymerization</term><term>Polymerization degree</term><term>Polymerization degrees</term><term>Present model</term><term>Present paper</term><term>Qssa</term><term>Rate coefficients</term><term>Reactor</term><term>Reactor axis</term><term>Real solutions</term><term>Remarkable property</term><term>Scission</term><term>Secondary carbon atoms</term><term>Secondary radicals</term><term>Several kinds</term><term>Short branches</term><term>Statistical moments</term><term>Structural characters</term><term>Tendency model</term><term>Total concentration</term><term>Transfer agent</term><term>Villermaux</term><term>Weight distribution</term></keywords></textClass><langUsage><language ident="en">en</language></langUsage></profileDesc></teiHeader><front><div type="abstract" xml:lang="en">Abstract: A specific approach based on a “tendecy model”, intermediate between the “black-box” and the “detailed analytical” models, has been developed. It makes it possible to predict both the amount of polymer produced in the autoclave process, and the quality of the polymer, expressed in terms of molecular structure: molecular-weight distribution (MWD), average molecular weights, long- and short-branching indices, double-bond indices. The prediction of conversion requires an appropriate representation of partial segregation of the initiator feedstream. The prediction of quality is based on a kinetic model taking into account the most important mechanism recognized for this reaction. Several kinds of free radicals are involved to which the quasi-steady-state assumption is applied. Processes giving rise to new chains are identified and the statistical moments for the corresponding distributions are derived. The moments of the overall dead polymer population are finally derived,thanks to a mixing theorem. In spite of the difficulties caused by transfer to polymer and scission of free radicals, equations for the moments are obtained in a closed form and this constituents a remarkable property of the present model. 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It makes it possible to predict both the amount of polymer produced in the autoclave process, and the quality of the polymer, expressed in terms of molecular structure: molecular-weight distribution (MWD), average molecular weights, long- and short-branching indices, double-bond indices. The prediction of conversion requires an appropriate representation of partial segregation of the initiator feedstream. The prediction of quality is based on a kinetic model taking into account the most important mechanism recognized for this reaction. Several kinds of free radicals are involved to which the quasi-steady-state assumption is applied. Processes giving rise to new chains are identified and the statistical moments for the corresponding distributions are derived. The moments of the overall dead polymer population are finally derived,thanks to a mixing theorem. In spite of the difficulties caused by transfer to polymer and scission of free radicals, equations for the moments are obtained in a closed form and this constituents a remarkable property of the present model. An expression for the MWD can then be obtained from its statistical moments by an original method based on the deformation of a known distribution.</abstract><qualityIndicators><score>7.436</score><pdfVersion>1.2</pdfVersion><pdfPageSize>550 x 720 pts</pdfPageSize><refBibsNative>true</refBibsNative><keywordCount>0</keywordCount><abstractCharCount>1370</abstractCharCount><pdfWordCount>5432</pdfWordCount><pdfCharCount>36812</pdfCharCount><pdfPageCount>12</pdfPageCount><abstractWordCount>203</abstractWordCount></qualityIndicators><title>Free-radical polymerization engineering—III. Modelling homogeneous polymerization of ethylene: mathematical model and new method for obtaining molecular-weight distribution</title><pii><json:string>0009-2509(92)85146-3</json:string></pii><genre><json:string>research-article</json:string></genre><host><title>Chemical Engineering Science</title><language><json:string>unknown</json:string></language><publicationDate>1992</publicationDate><issn><json:string>0009-2509</json:string></issn><pii><json:string>S0009-2509(00)X0612-4</json:string></pii><volume>47</volume><issue>15–16</issue><pages><first>3969</first><last>3980</last></pages><genre><json:string>journal</json:string></genre></host><categories><wos><json:string>science</json:string><json:string>engineering, chemical</json:string></wos><scienceMetrix><json:string>applied sciences</json:string><json:string>engineering</json:string><json:string>chemical engineering</json:string></scienceMetrix><inist><json:string>sciences appliquees, technologies et medecines</json:string><json:string>sciences exactes et technologie</json:string><json:string>chimie</json:string><json:string>chimie analytique</json:string></inist></categories><publicationDate>1992</publicationDate><copyrightDate>1992</copyrightDate><doi><json:string>10.1016/0009-2509(92)85146-3</json:string></doi><id>F2114A91EA51074353F30570A1CF47D9A10C023F</id><score>1</score><fulltext><json:item><extension>pdf</extension><original>true</original><mimetype>application/pdf</mimetype><uri>https://api.istex.fr/document/F2114A91EA51074353F30570A1CF47D9A10C023F/fulltext/pdf</uri></json:item><json:item><extension>zip</extension><original>false</original><mimetype>application/zip</mimetype><uri>https://api.istex.fr/document/F2114A91EA51074353F30570A1CF47D9A10C023F/fulltext/zip</uri></json:item><istex:fulltextTEI uri="https://api.istex.fr/document/F2114A91EA51074353F30570A1CF47D9A10C023F/fulltext/tei"><teiHeader><fileDesc><titleStmt><title level="a" type="main" xml:lang="en">Free-radical polymerization engineering—III. Modelling homogeneous polymerization of ethylene: mathematical model and new method for obtaining molecular-weight distribution</title></titleStmt><publicationStmt><authority>ISTEX</authority><publisher>ELSEVIER</publisher><availability><p>ELSEVIER</p></availability><date>1992</date></publicationStmt><sourceDesc><biblStruct type="inbook"><analytic><title level="a" type="main" xml:lang="en">Free-radical polymerization engineering—III. Modelling homogeneous polymerization of ethylene: mathematical model and new method for obtaining molecular-weight distribution</title><author xml:id="author-0000"><persName><forename type="first">Pascal</forename><surname>Lorenzini</surname></persName><note type="biography">Société Française de Polyéthyléne(SOFRAPO), Groupe Enimont, 11 rue del l'Abreuvoir,92411 Courbevoie Cedex, France.</note><affiliation>Société Française de Polyéthyléne(SOFRAPO), Groupe Enimont, 11 rue del l'Abreuvoir,92411 Courbevoie Cedex, France.</affiliation><affiliation>Laboratoire des Science du Génie Chimique, CNRS—ENSIC—Institut National Polytechnique de Lorraine, 1 rue Grandville, BP 451, 54001 Nancy Cedex, France</affiliation></author><author xml:id="author-0001"><persName><forename type="first">Michel</forename><surname>Pons</surname></persName><note type="biography">Société Française de Polyéthyléne(SOFRAPO), Groupe Enimont, 11 rue del l'Abreuvoir,92411 Courbevoie Cedex, France.</note><affiliation>Société Française de Polyéthyléne(SOFRAPO), Groupe Enimont, 11 rue del l'Abreuvoir,92411 Courbevoie Cedex, France.</affiliation><affiliation>Laboratoire des Science du Génie Chimique, CNRS—ENSIC—Institut National Polytechnique de Lorraine, 1 rue Grandville, BP 451, 54001 Nancy Cedex, France</affiliation></author><author xml:id="author-0002"><persName><forename type="first">Jacques</forename><surname>Villermaux</surname></persName><affiliation>Author to whom correspondence should be addressed.</affiliation><affiliation>Laboratoire des Science du Génie Chimique, CNRS—ENSIC—Institut National Polytechnique de Lorraine, 1 rue Grandville, BP 451, 54001 Nancy Cedex, France</affiliation></author><idno type="istex">F2114A91EA51074353F30570A1CF47D9A10C023F</idno><idno type="DOI">10.1016/0009-2509(92)85146-3</idno><idno type="PII">0009-2509(92)85146-3</idno><idno type="ArticleID">92851463</idno></analytic><monogr><title level="j">Chemical Engineering Science</title><title level="j" type="abbrev">CES</title><idno type="pISSN">0009-2509</idno><idno type="PII">S0009-2509(00)X0612-4</idno><imprint><publisher>ELSEVIER</publisher><date type="published" when="1992"></date><biblScope unit="volume">47</biblScope><biblScope unit="issue">15–16</biblScope><biblScope unit="page" from="3969">3969</biblScope><biblScope unit="page" to="3980">3980</biblScope></imprint></monogr></biblStruct></sourceDesc></fileDesc><profileDesc><creation><date>1992</date></creation><langUsage><language ident="en">en</language></langUsage><abstract xml:lang="en"><p>A specific approach based on a “tendecy model”, intermediate between the “black-box” and the “detailed analytical” models, has been developed. It makes it possible to predict both the amount of polymer produced in the autoclave process, and the quality of the polymer, expressed in terms of molecular structure: molecular-weight distribution (MWD), average molecular weights, long- and short-branching indices, double-bond indices. The prediction of conversion requires an appropriate representation of partial segregation of the initiator feedstream. The prediction of quality is based on a kinetic model taking into account the most important mechanism recognized for this reaction. Several kinds of free radicals are involved to which the quasi-steady-state assumption is applied. Processes giving rise to new chains are identified and the statistical moments for the corresponding distributions are derived. The moments of the overall dead polymer population are finally derived,thanks to a mixing theorem. In spite of the difficulties caused by transfer to polymer and scission of free radicals, equations for the moments are obtained in a closed form and this constituents a remarkable property of the present model. An expression for the MWD can then be obtained from its statistical moments by an original method based on the deformation of a known distribution.</p></abstract></profileDesc><revisionDesc><change when="1992">Published</change></revisionDesc></teiHeader></istex:fulltextTEI><json:item><extension>txt</extension><original>false</original><mimetype>text/plain</mimetype><uri>https://api.istex.fr/document/F2114A91EA51074353F30570A1CF47D9A10C023F/fulltext/txt</uri></json:item></fulltext><metadata><istex:metadataXml wicri:clean="Elsevier, elements deleted: tail"><istex:xmlDeclaration>version="1.0" encoding="UTF-8"</istex:xmlDeclaration><istex:docType PUBLIC="-//ES//DTD journal article DTD version 4.5.2//EN//XML" URI="art452.dtd" name="istex:docType"></istex:docType><istex:document><converted-article version="4.5.2" docsubtype="fla" xml:lang="en"><item-info><jid>CES</jid><aid>92851463</aid><ce:pii>0009-2509(92)85146-3</ce:pii><ce:doi>10.1016/0009-2509(92)85146-3</ce:doi><ce:copyright type="unknown" year="1992"></ce:copyright></item-info><head><ce:title>Free-radical polymerization engineering—III. Modelling homogeneous polymerization of ethylene: mathematical model and new method for obtaining molecular-weight distribution</ce:title><ce:author-group><ce:author><ce:given-name>Pascal</ce:given-name><ce:surname>Lorenzini</ce:surname><ce:cross-ref refid="FN1"><ce:sup loc="post">1</ce:sup></ce:cross-ref></ce:author><ce:author><ce:given-name>Michel</ce:given-name><ce:surname>Pons</ce:surname><ce:cross-ref refid="FN1"><ce:sup loc="post">1</ce:sup></ce:cross-ref></ce:author><ce:author><ce:given-name>Jacques</ce:given-name><ce:surname>Villermaux</ce:surname><ce:cross-ref refid="COR1"><ce:sup loc="post">§</ce:sup></ce:cross-ref></ce:author><ce:affiliation><ce:textfn>Laboratoire des Science du Génie Chimique, CNRS—ENSIC—Institut National Polytechnique de Lorraine, 1 rue Grandville, BP 451, 54001 Nancy Cedex, France</ce:textfn></ce:affiliation><ce:correspondence id="COR1"><ce:label>§</ce:label><ce:text>Author to whom correspondence should be addressed.</ce:text></ce:correspondence><ce:footnote id="FN1"><ce:label>1</ce:label><ce:note-para>Société Française de Polyéthyléne(SOFRAPO), Groupe Enimont, 11 rue del l'Abreuvoir,92411 Courbevoie Cedex, France.</ce:note-para></ce:footnote></ce:author-group><ce:date-received day="17" month="7" year="1991"></ce:date-received><ce:date-accepted day="29" month="10" year="1991"></ce:date-accepted><ce:abstract class="author"><ce:section-title>Abstract</ce:section-title><ce:abstract-sec><ce:simple-para view="all" id="simple-para.0010">A specific approach based on a “tendecy model”, intermediate between the “black-box” and the “detailed analytical” models, has been developed. It makes it possible to predict both the amount of polymer produced in the autoclave process, and the quality of the polymer, expressed in terms of molecular structure: molecular-weight distribution (MWD), average molecular weights, long- and short-branching indices, double-bond indices. The prediction of conversion requires an appropriate representation of partial segregation of the initiator feedstream. The prediction of quality is based on a kinetic model taking into account the most important mechanism recognized for this reaction. Several kinds of free radicals are involved to which the quasi-steady-state assumption is applied. Processes giving rise to new chains are identified and the statistical moments for the corresponding distributions are derived. The moments of the overall dead polymer population are finally derived,thanks to a mixing theorem. In spite of the difficulties caused by transfer to polymer and scission of free radicals, equations for the moments are obtained in a closed form and this constituents a remarkable property of the present model. An expression for the MWD can then be obtained from its statistical moments by an original method based on the deformation of a known distribution.</ce:simple-para></ce:abstract-sec></ce:abstract></head></converted-article></istex:document></istex:metadataXml><mods version="3.6"><titleInfo lang="en"><title>Free-radical polymerization engineering—III. Modelling homogeneous polymerization of ethylene: mathematical model and new method for obtaining molecular-weight distribution</title></titleInfo><titleInfo type="alternative" lang="en" contentType="CDATA"><title>Free-radical polymerization engineering—III. Modelling homogeneous polymerization of ethylene: mathematical model and new method for obtaining molecular-weight distribution</title></titleInfo><name type="personal"><namePart type="given">Pascal</namePart><namePart type="family">Lorenzini</namePart><affiliation>Laboratoire des Science du Génie Chimique, CNRS—ENSIC—Institut National Polytechnique de Lorraine, 1 rue Grandville, BP 451, 54001 Nancy Cedex, France</affiliation><description>Société Française de Polyéthyléne(SOFRAPO), Groupe Enimont, 11 rue del l'Abreuvoir,92411 Courbevoie Cedex, France.</description><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">Michel</namePart><namePart type="family">Pons</namePart><affiliation>Laboratoire des Science du Génie Chimique, CNRS—ENSIC—Institut National Polytechnique de Lorraine, 1 rue Grandville, BP 451, 54001 Nancy Cedex, France</affiliation><description>Société Française de Polyéthyléne(SOFRAPO), Groupe Enimont, 11 rue del l'Abreuvoir,92411 Courbevoie Cedex, France.</description><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">Jacques</namePart><namePart type="family">Villermaux</namePart><affiliation>Laboratoire des Science du Génie Chimique, CNRS—ENSIC—Institut National Polytechnique de Lorraine, 1 rue Grandville, BP 451, 54001 Nancy Cedex, France</affiliation><description>Author to whom correspondence should be addressed.</description><role><roleTerm type="text">author</roleTerm></role></name><typeOfResource>text</typeOfResource><genre type="research-article" displayLabel="Full-length article" authority="ISTEX" authorityURI="https://content-type.data.istex.fr" valueURI="https://content-type.data.istex.fr/ark:/67375/XTP-1JC4F85T-7">research-article</genre><originInfo><publisher>ELSEVIER</publisher><dateIssued encoding="w3cdtf">1992</dateIssued><copyrightDate encoding="w3cdtf">1992</copyrightDate></originInfo><language><languageTerm type="code" authority="iso639-2b">eng</languageTerm><languageTerm type="code" authority="rfc3066">en</languageTerm></language><abstract lang="en">Abstract: A specific approach based on a “tendecy model”, intermediate between the “black-box” and the “detailed analytical” models, has been developed. It makes it possible to predict both the amount of polymer produced in the autoclave process, and the quality of the polymer, expressed in terms of molecular structure: molecular-weight distribution (MWD), average molecular weights, long- and short-branching indices, double-bond indices. The prediction of conversion requires an appropriate representation of partial segregation of the initiator feedstream. The prediction of quality is based on a kinetic model taking into account the most important mechanism recognized for this reaction. Several kinds of free radicals are involved to which the quasi-steady-state assumption is applied. Processes giving rise to new chains are identified and the statistical moments for the corresponding distributions are derived. The moments of the overall dead polymer population are finally derived,thanks to a mixing theorem. In spite of the difficulties caused by transfer to polymer and scission of free radicals, equations for the moments are obtained in a closed form and this constituents a remarkable property of the present model. An expression for the MWD can then be obtained from its statistical moments by an original method based on the deformation of a known distribution.</abstract><relatedItem type="host"><titleInfo><title>Chemical Engineering Science</title></titleInfo><titleInfo type="abbreviated"><title>CES</title></titleInfo><genre type="journal" authority="ISTEX" authorityURI="https://publication-type.data.istex.fr" valueURI="https://publication-type.data.istex.fr/ark:/67375/JMC-0GLKJH51-B">journal</genre><originInfo><publisher>ELSEVIER</publisher><dateIssued encoding="w3cdtf">199210</dateIssued></originInfo><identifier type="ISSN">0009-2509</identifier><identifier type="PII">S0009-2509(00)X0612-4</identifier><part><date>199210</date><detail type="volume"><number>47</number><caption>vol.</caption></detail><detail type="issue"><number>15–16</number><caption>no.</caption></detail><extent unit="issue-pages"><start>3827</start><end>4224</end></extent><extent unit="pages"><start>3969</start><end>3980</end></extent></part></relatedItem><identifier type="istex">F2114A91EA51074353F30570A1CF47D9A10C023F</identifier><identifier type="ark">ark:/67375/6H6-VK4KMXXW-G</identifier><identifier type="DOI">10.1016/0009-2509(92)85146-3</identifier><identifier type="PII">0009-2509(92)85146-3</identifier><identifier type="ArticleID">92851463</identifier><recordInfo><recordContentSource authority="ISTEX" authorityURI="https://loaded-corpus.data.istex.fr" valueURI="https://loaded-corpus.data.istex.fr/ark:/67375/XBH-HKKZVM7B-M">elsevier</recordContentSource></recordInfo></mods><json:item><extension>json</extension><original>false</original><mimetype>application/json</mimetype><uri>https://api.istex.fr/document/F2114A91EA51074353F30570A1CF47D9A10C023F/metadata/json</uri></json:item></metadata><serie></serie></istex></record>Pour manipuler ce document sous Unix (Dilib)
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