THERMODYNAMIC DATA of COPOLYMER SOLUTIONS ppt

CRC HANDBOOK OF of THERMODYNAMIC DATA COPOLYMER SOLUTIONS © 2001 by CRC Press LLC Christian Wohlfarth CRC HANDBOOK OF of THERMODYNAMIC DATA COPOLYMER SOLUTIONS Boca Raton London New York Washington, D.C. CRC Press This book contains information obtained from authentic and highly regarded sources. Reprinted material is quoted with permission, and sources are indicated. A wide variety of references are listed. Reasonable efforts have been made to publish reliable data and information, but the author and the publisher cannot assume responsibility for the validity of all materials or for the consequences of their use. Neither this book nor any part may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, microfilming, and recording, or by any information storage or retrieval system, without prior permission in writing from the publisher. The consent of CRC Press LLC does not extend to copying for general distribution, for promotion, for creating new works, or for resale. Specific permission must be obtained in writing from CRC Press LLC for such copying. Direct all inquiries to CRC Press LLC, 2000 N.W. Corporate Blvd., Boca Raton, Florida 33431. Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation, without intent to infringe. Visit the CRC Press Web site at www.crcpress.com © 2001 by CRC Press LLC No claim to original U.S. Government works International Standard Book Number 0-8493-1074-1 Printed in the United States of America 1 2 3 4 5 6 7 8 9 0 Printed on acid-free paper Library of Congress Cataloging-in-Publication Data Catalog record is available from the Library of Congress 1074/Disclaimer Page 1 Tuesday, March 13, 2001 12:33 PM Foreword Practical applications of thermodynamics as well as theoretical calculations of thermodynamic properties generally require data of real systems. In most cases these data rest on laboratory measurements of various physical properties. The study of phase behavior and thermodynamic properties of polymers and mixtures containing polymers has been subject of interest during the last 50 years. Investigations on such properties for copolymer systems were emphasized during the last decade when copolymers gained an increasing commercial interest because of their unique physical properties. Much effort has been devoted over the years to compiling thermodynamic data for types of systems from literature and preparing compilations and databases for both scientific and industrial use. However, scarcely anything is found when one looks for compilations or databases that provide thermodynamic properties of polymer, or even more specially, copolymer solutions. Experimental information is spread over many articles and journals. There are only a small number of data books that cover this field. The author of this handbook wrote one of them on vapor-liquid equilibria of binary polymer solutions in 1994. He is known for his experience and his own experimental investigations on polymer and copolymer solutions for more than 20 years. With his new Handbook of Thermodynamic Data of Copolymer Solutions for the first time a compilation of thermodynamic data for copolymer solutions from the original literature is available. Taking into account vapor-liquid equilibrium (VLE) data, liquid-liquid equilibrium (LLE) data, high-pressure phase equilibrium (HPPE) data of copolymer solutions in supercritical fluids, volumetric property (PVT) data of copolymer melts, enthalpy data, and second osmotic virial coefficients of copolymer solutions, the book covers all the necessary areas for researchers and engineers who work in this field. When dealing with copolymer systems, one encounters the special problem of copolymer characterization since a copolymer is far from well-defined only by its chemical formula. Copolymers vary by a number of characterization variables. Molar mass, chemical composition, and distribution functions, tacticity, sequence distribution, branching, and end groups determine their thermodynamic behavior in solution. It is far from clear how these parameters influence the thermodynamic properties in detail. Unfortunately, there usually is not much information in the original papers; the available ones are added to each system in this book. In comparison to low-molecular systems, the amount of data for copolymer solutions is still rather small. About 300 literature sources were perused for the purpose of this handbook, including some dissertations and diploma papers. Several hundred vapor-pressure isotherms, Henry’s constants, LLE and HPPE data sets, a number of PVT data and some second osmotic virial coefficients are reported. I am sure that readers interested in the field of thermodynamic properties of polymer solutions will benefit from this handbook and will identify the work that has to be done in the future. Henry V. Kehiaian Chairman IUPAC-CODATA Task Group on Standard Physico-Chemical Data Formats © 2001 by CRC Press LLC PREFACE Knowledge of thermodynamic data of copolymer solutions is a necessity for industrial and laboratory processes. Such data serve as essential tools for understanding the physical behavior of copolymer solutions, for studying intermolecular interactions, and for gaining insights into the molecular nature of mixtures. They also provide the necessary basis for any developments of theoretical thermodynamic models. Scientists and engineers in academic and industrial research need such data and will benefit from a careful collection of existing data. The CRC Handbook of Thermodynamic Data of Copolymer Solutions provides a reliable collection of such data for copolymer solutions from the original literature. The Handbook is divided into seven chapters: (1) Introduction, (2) Vapor-Liquid Equilibrium (VLE) Data of Binary Copolymer Solutions, (3) Liquid-Liquid Equilibrium (LLE) Data of Quasibinary or Quasiternary Copolymer Solutions, (4) High-Pressure Phase Equilibrium (HPPE) Data of Quasibinary or Quasiternary Copolymer Solutions in Supercritical Fluids, (5) Enthalpy Changes for Binary Copolymer Solutions, (6) PVT Data of Molten Copolymers, and (7) Second Virial Coefficients (A 2 ) of Copolymer Solutions. Finally, four appendices quickly route the user to the desired data sets. Original data have been gathered from approximately 300 literature sources, including also a number of dissertations and diploma papers. The Handbook provides about 250 vapor-pressure isotherms, 75 tables of Henry’s constants, 50 LLE data sets, 175 HPPE data sets, and 70 PVT data tables for more than 165 copolymers and 165 solvents. Data are included only if numerical values were published or authors provided their numerical results by personal communication (and I wish to thank all those who did so). No digitized data have been included in this data collection, but some tables include systems data published in graphical form. The Handbook is the first complete overview about this subject in the world’s literature. The closing day for the data collection was October 1, 2000. The Handbook results from parts of a more general database, Thermodynamic Properties of Polymer Systems, which is continuously updated by the author. Thus, the user who is in need for new additional data sets is kindly invited to ask for new information beyond this book via e-mail at wohlfarth@chemie.uni-halle.de. Additionally, the author will be grateful to users who call his attention to mistakes and make suggestions for improvements. The Handbook also highlights the work still to be done − obvious, when one compares the relatively small number of copolymer solutions for which data exist with the number of copolymers in use today. Additionally, only a small minority of possible solutions of the copolymers covered by this book were properly investigated (in relation to the combinatorial number of copolymer/solvent pairs, although it is appreciated that not all make thermodynamic sense or are of practical use). The CRC Handbook of Thermodynamic Data of Copolymer Solutions will be useful to researchers, specialists, and engineers working in the fields of polymer science, physical chemistry, chemical engineering, material science, and those developing computerized predictive packages. The Handbook should also be of use as a data source to Ph.D. students and faculty in Chemistry, Physics, Chemical Engineering, and Materials Science Departments at universities. Merseburg, January 2001 Christian Wohlfarth © 2001 by CRC Press LLC About the Author Christian Wohlfarth is Associate Professor for Physical Chemistry at Martin Luther University Halle-Wittenberg, Germany. He earned his degree in Chemistry in 1974 and wrote his Ph.D. thesis on investigations on the second dielectric virial coefficient and the intermolecular pair potential in 1977, both at Carl Schorlemmer Technical University Merseburg. In 1985, he wrote his habilitation thesis, Phase Equilibria in Systems with Polymers and Copolymers, at Technical University Merseburg. Since then, his main research is related to polymer systems. Currently, his research topics are molecular thermodynamics, continuous thermodynamics, phase equilibria in (co)polymer mixtures and solutions, (co)polymers in supercritical fluids, PVT-behavior and equations of state, sorption properties of (co)polymers, about which he has published approximately 90 original papers. He has also built a database, Thermodynamic Properties of Polymer Systems, and has written the book Vapor-Liquid Equilibria of Binary Polymer Solutions. He is working on the evaluation, correlation, and calculation of thermophysical properties of pure compounds and mixtures resulting in 6 volumes of Landolt-Börnstein New Series. He is a member of the Editorial Board of ELDATA: The International Electronic Journal of Physico-Chemical Data. © 2001 by CRC Press LLC CONTENTS 1. INTRODUCTION 1.1. Objectives of the handbook 1.2. Experimental methods involved 1.3. Guide to the data tables 1.4. List of symbols 1.5. References 2. VAPOR-LIQUID EQUILIBRIUM (VLE) DATA OF BINARY COPOLYMER SOLUTIONS 2.1. Partial solvent vapor pressures or solvent activities for copolymer solutions 2.2. Classical mass-fraction Henry's constants of solvent vapors in molten copolymers 2.3. References 3. LIQUID-LIQUID EQUILIBRIUM (LLE) DATA OF QUASIBINARY OR QUASITERNARY COPOLYMER SOLUTIONS 3.1. Cloud-point and/or coexistence curves of quasibinary solutions 3.2. Table of systems where binary LLE data were published only in graphical form as phase diagrams or related figures 3.3. Cloud-point and/or coexistence curves of quasiternary solutions containing at least one copolymer 3.4. Table of systems where ternary LLE data were published only in graphical form as phase diagrams or related figures 3.5. Lower critical (LCST) and/or upper (UCST) critical solution temperatures of copolymer solutions 3.6. References 4. HIGH-PRESSURE PHASE EQUILIBRIUM (HPPE) DATA OF COPOLYMER SOLUTIONS IN SUPERCRITICAL FLUIDS 4.1. Experimental data of quasibinary copolymer solutions 4.2. Table of systems where binary HPPE data were published only in graphical form as phase diagrams or related figures 4.3. Experimental data of quasiternary solutions containing at least one copolymer 4.4. Table of systems where ternary HPPE data were published only in graphical form as phase diagrams or related figures 4.5. References © 2001 by CRC Press LLC 5. ENTHALPY CHANGES FOR BINARY COPOLYMER SOLUTIONS 5.1. Enthalpies of mixing or intermediary enthalpies of dilution, and copolymer partial enthalpies of mixing (at infinite dilution), or copolymer (first) integral enthalpies of solution 5.2. Partial molar enthalpies of mixing at infinite dilution of solvents and enthalpies of solution of gases/vapors of solvents in molten copolymers from inverse gas-liquid chromatography (IGC) 5.3. Table of systems where additional information on enthalpy effects in copolymer solutions can be found 5.4. References 6. PVT DATA OF MOLTEN COPOLYMERS 6.1. Experimental data and/or Tait equation parameters 6.2. References 7. SECOND VIRIAL COEFFICIENTS (A 2 ) OF COPOLYMER SOLUTIONS 7.1. Experimental A 2 data 7.2. References 8. APPENDICES 8.1. List of copolymer acronyms 8.2. List of systems and properties in order of the copolymers 8.3. List of solvents in alphabetical order 8.4. List of solvents in order of their molecular formulas © 2001 by CRC Press LLC 1. INTRODUCTION 1.1. Objectives of the handbook Knowledge of thermodynamic data of copolymer solutions is a necessity for industrial and laboratory processes. Furthermore, such data serve as essential tools for understanding the physical behavior of copolymer solutions, for studying intermolecular interactions, and for gaining insights into the molecular nature of mixtures. They also provide the necessary basis for any developments of theoretical thermodynamic models. Scientists and engineers in academic and industrial research need such data and will benefit from a careful collection of existing data. However, the database for polymer solutions is still modest in comparison with the enormous amount of data for low-molecular mixtures, and the specialized database for copolymer solutions is even smaller. On the other hand, copolymers are gaining increasing commercial interest because of their unique physical properties, and thermodynamic data are needed for optimizing their synthesis, production, and application. Basic information on polymers as well as copolymers can be found in the Polymer Handbook (99BRA). Some data books on polymer solutions appeared in the early 1990s (90BAR, 92WEN, 93DAN, and 94WOH), but most data for copolymer solutions have been compiled during the last decade. No books or databases dedicated to copolymer solutions presently exist. Thus, the intention of the Handbook is to fill this gap and to provide scientists and engineers with an up-to-date compilation from the literature of the available thermodynamic data on copolymer solutions. The Handbook does not present theories and models for (co)polymer solution thermodynamics. Other publications (71YAM, 90FUJ, 90KAM, and 99PRA) can serve as starting points for investigating those issues. The data within this book are divided into six chapters: • Vapor-liquid equilibrium (VLE) data of binary copolymer solutions • Liquid-liquid equilibrium (LLE) data of quasibinary or quasiternary copolymer solutions • High-pressure phase equilibrium (HPPE) data of copolymer solutions in supercritical fluids • Enthalpy changes for binary copolymer solutions • PVT data of molten copolymers • Second virial coefficients (A 2 ) of copolymer solutions Data from investigations applying to more than one chapter are divided and appear in the relevant chapters. Data are included only if numerical values were published or authors provided their numerical results by personal communication (and I wish to thank all those who did so). No digitized data have been included in this data collection, but some tables include systems data published in graphical form. This volume also highlights the work still to be done − obvious, when one compares the relatively small number of copolymer solutions for which data exist with the number of copolymers in use today. Additionally, only a small minority of possible solutions of the copolymers covered by this book were properly investigated (in relation to the combinatorial number of copolymer/solvent pairs, although it is appreciated that not all make thermodynamic sense or are of practical use). Very few investigations involved thermodynamic data for particular copolymer solutions, and the temperature (and/or pressure) ranges usually investigated are rather limited. The Handbook provides the results of recent research, and clearly identifies areas that require further exploration in the future. © 2001 by CRC Press LLC 1.2. Experimental methods involved Vapor-liquid equilibrium (VLE) measurements Investigations on vapor-liquid equilibrium of polymer solutions can be made by various methods: 1. Absolute vapor pressure measurement 2. Differential vapor pressure measurement 3. Isopiestic sorption/desorption methods, i.e., gravimetric sorption, piezoelectric sorption, or isothermal distillation 4. Inverse gas-liquid chromatography (IGC) at infinite dilution, IGC at finite concentrations, and headspace gas chromatography (HSGC) 5. Steady-state vapor-pressure osmometry (VPO) Experimental techniques for vapor pressure measurements were reviewed in 75BON and 2000WOH. Methods and results of the application of IGC to polymers and polymer solutions were more often reviewed (76NES, 88NES, 89LLO, 89VIL, and 91MU1). Reviews on ebulliometry and/or vapor- pressure osmometry can be found in 74TOM, 75GLO, 87COO, 91MAY, and 99PET. The measurement of vapor pressures for polymer solutions is generally more difficult and more time-consuming than that of low-molecular mixtures. The main difficulties can be summarized as follows: Polymer solutions exhibit strong negative deviations from Raoult’s law. These are mainly due to the large entropic contributions caused by the difference between the molar volumes of solvents and polymers as was explained by the classical Flory-Huggins theory about 60 years ago. However, because of this large difference in molar mass, vapor pressures of dilute solutions do not differ markedly from the vapor pressure of the pure solvent at the same temperature, even at polymer concentrations of 10-20 wt%. This requires special techniques to measure very small differences in solvent activities. Concentrated polymer solutions are characterized by rapidly increasing viscosities with increasing polymer concentration. This leads to a strong increase in time required to obtain real thermodynamic equilibrium caused by slow solvent diffusion effects (in or out of a non-equilibrium-state polymer solution). Furthermore, only the solvent coexists in both phases because polymers do not evaporate. The experimental techniques used for the measurement of vapor pressures of polymer solutions have to take into account all these effects. Vapor pressures of polymer solutions are usually measured in the isothermal mode by static methods. Dynamic methods are seldom applied, e.g., ebulliometry (75GLO and 87COO). At least, one can consider measurements by VPO to be dynamic ones, where a dynamic (steady-state) balance is obtained. Limits for the applicable ranges of polymer concentration and polymer molar mass, limits for the solvent vapor pressure and the measuring temperature and some technical restrictions prevent its broader application, however. Static techniques usually work at constant temperature. The three different methods (1 through 3 above) were used to determine most of the vapor pressures of polymer solutions in the literature. All three methods have to solve the problems of establishing real thermodynamic equilibrium between liquid polymer solution and solvent vapor phase, long-time temperature constancy during the experiment, determination of the final polymer concentration, and determination of pressure and/or activity. Absolute vapor pressure measurement and differential vapor pressure methods were mostly used by early workers. Most recent measurements were done with the isopiestic sorption methods. Gas-liquid chromatography as IGC closes the gap at high polymer concentrations where vapor pressures cannot be measured with sufficient accuracy. HSGC can be considered as some combination of absolute vapor pressure measurement with GLC. The following text (a short summary from the author’s own review, 2000WOH) explains briefly the usual experimental equipment and the measuring procedures. © 2001 by CRC Press LLC [...]... concentration of solvent A (mass/volume) concentration of copolymer B mass of solvent A mass of copolymer B molar mass of the solvent A molar mass of the copolymer B number-average relative molar mass molar mass of a basic unit of the copolymer B amount of substance of solvent A amount of substance of copolymer B segment number of the solvent A, usually rA = 1 segment number of the copolymer B volume of the... enthalpy of vaporization of the pure solvent A at temperature T integral enthalpy of mixing of copolymer B partial molar (or specific) enthalpy of mixing of copolymer B partial molar (or specific) enthalpy of mixing at infinite dilution of copolymer B integral enthalpy of solution of copolymer B partial molar (or specific) enthalpy of solution of copolymer B first integral enthalpy of solution of copolymer. .. fraction of solvent A mass fraction of copolymer B mole fraction of solvent A mole fraction of copolymer B base mole fraction of solvent A base mole fraction of copolymer B © 2001 by CRC Press LLC ϕA ϕB ρA ρB ψA ψB volume fraction of solvent A volume fraction of copolymer B density of solvent A density of copolymer B segment fraction of solvent A segment fraction of copolymer B For high-molecular copolymers,... relationship molar mass of the copolymer species Bi amount of substance of copolymer species Bi mass fraction of copolymer species Bi © 2001 by CRC Press LLC (34) The data tables of each chapter are provided below in order of the copolymers The tables in all the following chapters always begin with a summary of the available characterization data for the corresponding samples of a given kind of copolymer An acronym... enthalpy of solution of the copolymer B is measured by mixing isothermally a large excess of pure solvent and a certain amount of the copolymer to form a homogeneous solution The state of the copolymer before dissolution can significantly affect the enthalpy of solution An amorphous copolymer below its glass transition temperature Tg often dissolves with the release of heat The enthalpy of solution of a... int ∆ MH B mB wB xB integral enthalpy of solution of copolymer B integral enthalpy of mixing of copolymer B mass of copolymer B mass fraction of copolymer B mole fraction of copolymer B © 2001 by CRC Press LLC (13c) (13d) As stated above, the difference between int∆solHB and int∆MHB is determined by any enthalpic effects caused from solid-liquid phase transition of the crystallites and/or from glass... molten copolymer B (integral) intermediary enthalpy of dilution ( = ∆MH(2) − ∆MH(1)) (integral) enthalpy of mixing (integral) enthalpy of solution integral enthalpy of mixing of solvent A ( = integral enthalpy of dilution) partial molar enthalpy of mixing of the solvent A ( = differential enthalpy of dilution) partial molar enthalpy of mixing at infinite dilution of the solvent A integral enthalpy of solution... integral enthalpy of solution of solvent A partial molar enthalpy of solution of the solvent A first integral enthalpy of solution of solvent A (= ∆MHA∞ in the case of liquid/molten copolymers and a liquid solvent, i.e., it is different from the values for solutions of solvent vapors or gases in a liquid/molten copolymer ∆solHA(vap)∞ ) first integral enthalpy of solution of the vapor of solvent A (with ∆solHA(vap)∞... Press LLC (12a) (12b) where: ∆ Mh ∆solh HA HB H0A H0B nA nB (integral) enthalpy of mixing (integral) enthalpy of solution partial molar enthalpy of solvent A partial molar enthalpy of copolymer B molar enthalpy of pure solvent A molar enthalpy of pure copolymer B amount of substance of solvent A amount of substance of copolymer B The enthalpy effect might be positive (endothermic solution/mixture)... mole fraction of copolymer B base mole fraction of solvent A base mole fraction of copolymer B critical exponent activity coefficient of the solvent A in the liquid phase with activity aA = xAγA wavelength volume fraction of solvent A volume fraction of copolymer B density of solvent A density of copolymer B segment fraction of solvent A segment fraction of copolymer B osmotic pressure scattering angle . CRC HANDBOOK OF of THERMODYNAMIC DATA COPOLYMER SOLUTIONS © 2001 by CRC Press LLC Christian Wohlfarth CRC HANDBOOK OF of THERMODYNAMIC DATA COPOLYMER SOLUTIONS Boca Raton London. more than 20 years. With his new Handbook of Thermodynamic Data of Copolymer Solutions for the first time a compilation of thermodynamic data for copolymer solutions from the original literature. temperatures of copolymer solutions 3.6. References 4. HIGH-PRESSURE PHASE EQUILIBRIUM (HPPE) DATA OF COPOLYMER SOLUTIONS IN SUPERCRITICAL FLUIDS 4.1. Experimental data of quasibinary copolymer solutions 4.2.