DOCSLIB.ORG

ANNUAL REPORT 2013 COVER Plasma Discharge in Synthetic Air

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
ANNUAL REPORT 2013 COVER Plasma Discharge in Synthetic Air FRAUNHOFER INSTITUTE FOR SURFACE ENGINEERING AND THIN FILMS IST ANNUAL REPORT 2013 COVER Plasma discharge in synthetic air. FRAUNHOFER IST 1 FOREWORD FOREWORD Ladies and gentlemen, 1 On the left: deputy director Prof. Wolfgang Diehl. On the right: the year 2013 was a very successful year for the Fraunhofer Institute for Surface Engineering director Prof. Dr. Günter Bräuer. and Thin Films IST in many ways. We can look back on important awards and numerous new research results. We would like to take this opportunity to express our thanks to all people whose hard work and commitment made our success possible in the first place: above all the employees of the Fraunhofer IST, our partners from research and development, our customers from industry, our sponsors, colleagues and friends. Thank you for a trusting cooperation. We provide you with a selection of the most important developments of the Fraunhofer IST in the annual report at hand. We hope you enjoy the reading and are looking forward to your ideas for cooperation in future. Prof. Dr. Günter Bräuer Prof. Wolfgang Diehl 3 FRAUNHOFER IST CONTENT Foreword 3 Mechanical and automotive engineering 33 Optics and electronics 63 The Fraunhofer IST in Networks 101 Hard work for thin films 34 Uniform coatings on the EOSS® platform 64 The Fraunhofer-Gesellschaft at a glance 103 Highlights 2013 6 Carbon coatings for applications in fusion reactors 36 PECVD coatings for optical coating systems 66 Fraunhofer Group for Light & Surfaces 104 Thermoresistive thin-film sensor system Scratch-resistant antireflective coatings 68 Encouragement of young Fraunhofer prize 2013 8 for monitoring engine components 38 talent at the Fraunhofer IST 106 Oxidic electronics for flexible applications 70 Surfaces for efficient fuel cells 40 INPLAS – Network of competence Prizes and awards in 2013 10 Plastic metallization with ions 72 industrial plasma surface technology 108 Aerospace 43 Memberships 110 From the board of trustees 12 Life science and ecology 75 Thin films on a long journey 44 Board memberships 111 Coatings for cell cultivation 76 Outstanding collaboration 15 Filigree electroplating: metallized carbon fibers 46 International guests 114 Surfaces for droplet-based microfluidics 78 Load monitoring of critical components Creation of functional coating structures 80 Institute profile 16 in rotor testing technology 48 Publications 114 ISO compliant turnkey-solutions Lectures, posters 118 for measuring NOX-degradation 82 The institute in figures 18 Tools 51 Dissertations 122 Sensor modules for plastic injection molding 52 Services and competencies 85 Diploma thesis / Master‘s thesis 123 Your contact person 22 Wear protection for forging dies 54 An overview of our competencies 86 Bachelor‘s thesis 124 The scope of research and services 24 Fast yet precise: ball-cratering3 88 Patent applications 125 Energy, glass and façade 57 Analysis and quality assurance 26 Emission spectroscopy and Electrolyte coatings for SOFC Special equipment 28 atmospheric-pressure plasma 90 Appendix 126 with gas-flow sputtering 58 New PACVD / PVD hybrid coating system 92 Picture index 126 Sustainable solutions with surface Atomic layer deposition 60 and thin film engineering 30 Editorial notes 127 Names, dates, events 2013 95 Trade fairs and exhibitions 96 Events, colloquia, workshops 98 4 5 FRAUNHOFER IST 1 2 HIGHLIGHTS 2013 “Cells snuggle up in the mini-lab” and “Deep thoughts about contributing over a million euros to the institute‘s balance on Fundamentals and Applications of High Impulse Power 1 Dr. Michael Thomas with surfaces – plasma coatings have conquered our daily lives”: sheet. One of the major topics here is the treatment of Magnetron Sputtering was held in Braunschweig for the the plasma bag coater. with these headlines in June 2013 the Braunschweiger Zeitung organic surfaces. Physicians are in urgent need of a gentle second time and was attended by around 150 experts from acknowledged the work of the Fraunhofer IST. Also in June, yet efficient treatment for skin and nail diseases or a faster 25 countries. 2 Prof. Dr. Wolfgang Viöl five Braunschweig researchers received the highly esteemed healing of wounds after injuries or surgical interventions. presents the plasma comb. Fraunhofer prize for human-centered technology for their Atmospheric-pressure plasmas can play an important role Despite developments of this kind, plasma is frequently still “Plasma in a bag” research. They work at the Helmholtz here. The scientists in Göttingen are also working on further regarded as a “subset” of optical technologies. However this Centre for Infection Research, at the Braunschweig Municipal innovations: the “plasma comb” kills unappetizing pests such does not live up to the importance of this key instrument. Hospital (Städtisches Klinikum Braunschweig) and at the as head lice or bedbugs, seeds are rendered germ-free, and Although plasma may appear in its most beautiful form as the Fraunhofer IST. Plastic bags are conditioned with atmospheric- the plasma in the vacuum cleaner is a deadly trap for dust aurora borealis, it is still a lot more than simply lights in the pressure plasmas for the cultivation of stem cells from which mites. One extremely positive side-effect associated with this sky. For most plasma processes this illumination is irrelevant “spare parts” are ultimately to be produced for the human work is the increasing number of young and talented female and only a free gift from nature. body. This research project is a classic example of interdis- scientists from the fields of biology and biotechnology who ciplinary collaboration between plasma chemists, biologists are enriching our research activities. “Talenta” is also the The editor-in-chief of Metalloberfläche (mo), a periodical and medical scientists and a further contribution towards a name of an internal Fraunhofer project within which we have dedicated to metallic surfaces, headlined his editorial in a discipline which is still young – plasma medicine. already been able to foster the careers of four young female recent edition with the words “The future spells plasma”. This researchers. At this point I should like to express my thanks to is a statement with which I wholeheartedly agree. With the establishment of the Application Center for Plasma our central office for this opportunity. and Photonics (APP) in collaboration with HAWK University I wish you great enjoyment in reading the report of our for applied Science and Art in Göttingen our institute has With its comprehensive equipment and its competence in the activities, taken another important step towards plasma medicine. field of high-ionized low-pressure plasma, the Fraunhofer IST Since its dedication in the summer of 2012, the IST‘s center has also developed an outstanding reputation at national in Göttingen has developed outstandingly well and is already and international level. In 2013 the International Conference Günter Bräuer 6 7 FRAUNHOFER IST 1 2 FRAUNHOFER PRIZE FOR HUMAN-CENTERED TECHNOLOGY 2013 It sounds like one of those brainteasers where you have to At the Helmholtz Centre for Infection Research (HZI) in Braun- For their work on developing plasma in bags for cell cultivation 1 Dr. Kurt E. J. Dittmar, change a matchstick figure into something else without schweig Dr. Werner Lindenmaier and Dr. Kurt Dittmar were in closed systems Dr. Kristina Lachmann, Dr. Michael Thomas, Dr. Michael Thomas, adding or taking away any matches: How do you modify already been working on bags for cultivating stem cells but Dr. Henk Garritsen, Dr. Werner Lindenmaier and Dr. Kurt Dr. Kristina Lachmann, the inside of a closed bag without opening it? Impossible, I without the success they were looking for. The geographical E. J. Dittmar have been awarded with the Fraunhofer prize Dr. Werner Lindenmaier, hear you say. But that is precisely what a team of researchers proximity and the expertise of Fraunhofer IST researchers in for human-centered technology. The prize in the amount Dr. Henk Garritsen and around Dr. Kristina Lachmann and Dr. Michael Thomas at the the field of plasma coating brought the two teams together. of 50,000 euros is granted every two years and founded by Dr. Hans-Ulrich Wiese, Fraunhofer Institute for Surface Engineering and Thin Films IST Initial tests showed that the cells grow on plasma-coated films. former executive board members and institute directors of former director of in Braunschweig have managed to do. They use plasma to In a joint project sponsered by the German Federal Ministry of the Fraunhofer-Gesellschaft and the Fraunhofer Excellence human ressources of the activate the interior surfaces of plastic bags. The plasma acts Economics and Technology (BMWi), the closed bag system and Foundation. It honors developments which make a significant Fraunhofer-Gesellschaft, (left as a disinfectant while also transfroming the surface of the cell growth were to be investigated in greater detail. contribution to improving people‘s quality of life. to right) after being awarded bag such so that cells want and are able to grow on it. with the Fraunhofer prize. The key part of the method is coating with plasma. To achieve The project-partners “Our goal was to realize a closed system in which cells grow this, ordinary bags such as those used for blood infusions are Helmholtz Centre for Infection Research Therapeutic 2 The five awardees with undisturbed and without the risk of contamination”, says filled with a noble gas and voltage is applied. “This produces Cellular Vaccines their development, plasma Dr. Henk Garritsen from Braunschweig Municipal Hospital plasma inside the bag for a short period – a luminous ionized Inhoffenstraße 7 in a bag for cell cultivation in 38124 Braunschweig (Städtisches Klinikum Braunschweig). “Coating the bags gas that chemically modifies and at the same time disinfects closed systems. www.helmholtz-hzi.de/en with plasma enables us to use them as a GMP laboratory. the plastic surface”, explains Dr. Kristina Lachmann from Institut für Klinische Transfusionsmedizin GMP stands for good manufacturing practice – for quality Fraunhofer IST.
Load more

Recommended publications
  • Thin Film Metallization and Protective Top-Coat Development
    University of Windsor Scholarship at UWindsor Electronic Theses and Dissertations 2011 Thin iF lm Metallization and Protective Top-Coat Development Jack Bekou University of Windsor Follow this and additional works at: http://scholar.uwindsor.ca/etd Recommended Citation Bekou, Jack, "Thin iF lm Metallization and Protective Top-Coat Development" (2011). Electronic Theses and Dissertations. Paper 174. This online database contains the full-text of PhD dissertations and Masters’ theses of University of Windsor students from 1954 forward. These documents are made available for personal study and research purposes only, in accordance with the Canadian Copyright Act and the Creative Commons license—CC BY-NC-ND (Attribution, Non-Commercial, No Derivative Works). Under this license, works must always be attributed to the copyright holder (original author), cannot be used for any commercial purposes, and may not be altered. Any other use would require the permission of the copyright holder. Students may inquire about withdrawing their dissertation and/or thesis from this database. For additional inquiries, please contact the repository administrator via email ([email protected]) or by telephone at 519-253-3000ext. 3208. Thin Film Metallization and Protective Top-Coat Development By Jack Bekou A Thesis Submitted to the Faculty of Graduate Studies Through the Department of Mechanical, Automotive and Materials Engineering In Partial Fulfillment of the Requirements for the Degree of Master of Applied Science at the University of Windsor Windsor, Ontario, Canada 2011 © 2011 Jack Bekou Thin Film Metallization and Protective Top-Coat Development By Jack Bekou APPROVED BY: ____________________________________________ Dr. Xueyuan Nie, Program Reader, Department of Mechanical, Automotive & Materials Engineering ____________________________________________ Dr.
    [Show full text]
  • Formation of Highly Electrically Conductive Surface-Silvered Polyimide Films Under Exceptionally Mild Conditions
    W&M ScholarWorks Undergraduate Honors Theses Theses, Dissertations, & Master Projects 5-2010 Formation of Highly Electrically Conductive Surface-Silvered Polyimide Films Under Exceptionally Mild Conditions Tyler Stukenbroeker College of William and Mary Follow this and additional works at: https://scholarworks.wm.edu/honorstheses Part of the Chemistry Commons Recommended Citation Stukenbroeker, Tyler, "Formation of Highly Electrically Conductive Surface-Silvered Polyimide Films Under Exceptionally Mild Conditions" (2010). Undergraduate Honors Theses. Paper 666. https://scholarworks.wm.edu/honorstheses/666 This Honors Thesis is brought to you for free and open access by the Theses, Dissertations, & Master Projects at W&M ScholarWorks. It has been accepted for inclusion in Undergraduate Honors Theses by an authorized administrator of W&M ScholarWorks. For more information, please contact [email protected]. Formation of Highly Electrically Conductive Surface-Silvered Polyimide Films Under Exceptionally Mild Conditions A thesis submitted in partial fulfillment of the requirement for the degree of Bachelors of Science in Chemistry from The College of William and Mary by Tyler Stukenbroeker Accepted for (Honors, High Honors, Highest Honors) David Thompson, Director Christopher Abelt Gary Rice Clay Clemens Williamsburg, VA May 5, 2010 Table of Contents INTRODUCTION Background of Polyimide Synthesis and Characterization 4 EXPERIMENTAL SECTION Experimental Materials 11 Characterization Techniques and Procedure 15 Room Temperature Metallization
    [Show full text]
  • Silver and Gold Coating
    Copyright © Tarek Kakhia. All rights reserved. http://tarek.kakhia.org Gold & Silver Coatings By A . T . Kakhia 1 Copyright © Tarek Kakhia. All rights reserved. http://tarek.kakhia.org 2 Copyright © Tarek Kakhia. All rights reserved. http://tarek.kakhia.org Part One General Knowledge 3 Copyright © Tarek Kakhia. All rights reserved. http://tarek.kakhia.org 4 Copyright © Tarek Kakhia. All rights reserved. http://tarek.kakhia.org Aqua Regia ( Royal Acid ) Freshly prepared aqua regia is colorless, Freshly prepared aqua but it turns orange within seconds. Here, regia to remove metal fresh aqua regia has been added to these salt deposits. NMR tubes to remove all traces of organic material. Contents 1 Introduction 2 Applications 3 Chemistry 3.1 Dissolving gold 3.2 Dissolving platinum 3.3 Reaction with tin 3.4 Decomposition of aqua regia 4 History 1 - Introduction Aqua regia ( Latin and Ancient Italian , lit. "royal water"), aqua regis ( Latin, lit. "king's water") , or nitro – hydro chloric acid is a highly corrosive mixture of acids, a fuming yellow or red solution. The mixture is formed by freshly mixing concentrated nitric acid and hydro chloric acid , optimally in a volume ratio of 1:3. It was named 5 Copyright © Tarek Kakhia. All rights reserved. http://tarek.kakhia.org so because it can dissolve the so - called royal or noble metals, gold and platinum. However, titanium, iridium, ruthenium, tantalum, osmium, rhodium and a few other metals are capable of with standing its corrosive properties. IUPAC name Nitric acid hydro chloride Other names aqua regia , Nitro hydrochloric acid Molecular formula HNO3 + 3 H Cl Red , yellow or gold Appearance fuming liquid 3 Density 1.01–1.21 g / cm Melting point − 42 °C Boiling point 108 °C Solubility in water miscible in water Vapor pressure 21 mbar 2 – Applications Aqua regia is primarily used to produce chloro auric acid, the electrolyte in the Wohl will process.
    [Show full text]
  • The Foundations of Vacuum Coating Technology
    The Foundations of Vacuum Coating Technology The Foundations of Vacuum Coating Technology Donald M. Mattox Management Plus, Inc. Albuquerque, New Mexico NOYES PUBLICATIONS WILLIAM ANDREW PUBLISHING Norwich, New York, U.S.A. i Copyright © 2003, Noyes Publications / William Andrew Publishing. All rights reserved. No part of this book may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without permission in writing from the Publisher. Cover Art © 2003 by Brent Beckley / William Andrew Publishing Library of Congress Catalog Card Number: 2003004260 ISBN: 0-8155-1495-6 Published in the United States of America by Noyes / William Andrew Publishing 13 Eaton Avenue Norwich, NY 13815 1-800-932-7045 www.williamandrew.com www.knovel.com 10 9 8 7 6 5 4 3 2 1 This book may be purchased in quantity at discounts for education, business, or sales promotional use by contacting the Publisher. Plastics Design Library and its logo are trademarks of William Andrew Inc. Notice: To the best of our knowledge the information in this publication is accurate; however the Publisher does not assume any responsibility or liability for the accuracy or completeness of, or consequences arising from, such information. This book is intended for informational purposes only. Mention of trade names or commercial products does not constitute endorsement or recommendation for use by the Publisher. Final determination of the suitability of any information or product for any use, and the manner of that use, is the sole responsibility of the user.
    [Show full text]
  • Vacuum Metallizing-Quality and Productivity Enhancements Through In-Line Technology by John H
    Vacuum Metallizing-Quality and Productivity Enhancements Through In-Line Technology by John H. Durant, Durant, I.H. 1995. Yonrum Uelallizing: Quliry and Pmducfiviv Mill Lane Engineering Co. Inc., Lowell, Mass. Enhoncemnfs ntrough In-Line techno log^ Metal Finishing 9313). 27- 29. Reprinted with permission f”Elsevier Science Inc. .- acuum mating. frequently des- ically. The basecoating of lacquer fills together with virtually total exclusion ignated physical vapor deposi- in minor imperfections, which would of dust and other contaminants-for Vtion or PVD. offers an intriguing otherwise require buffing and polishing. example, for semiconductor wafer variety of solutions to application prob- The vacuum-deposited film of alumi- processing-in quantities that in- lems as well as relief from the increas- num (aluminized) may receive a trans- creased to undreamed-of levels. ingly astly business of handling, trans- parent topcoating for additional protec- Although the two applications cited porting. and disposing of the toxic and tion or perhaps color tinting. if requircd. are as diverse as one could select, they hszprdour wastes associated with vari- The use of an organic basecoat on a share in-line technology. As part sizes ws chemical plating processes. metal part, in effect, presents a surface increase or as requirements for ex- Production vacuum evaporation was that is quite similar to that of a molded tremely close process control and for a first employed by the optical industry or extruded plastic part. Thus, a mer- clean. uniform process environment in the 1930s for depositing thin magne- chant metallizer has the opportunity to tighten, the technical limitations of sium fluoride glare-resistant films on serve a wider market than would be batch systems become apparent.
    [Show full text]
  • Handbook of Chemical Vapor Deposition (Cvd)
    HANDBOOK OF CHEMICAL VAPOR DEPOSITION (CVD) Principles, Technology, and Applications Second Edition by Hugh O. Pierson Consultant and Sandia National Laboratories (retired) Albuquerque, New Mexico NOYES PUBLICATIONS Park Ridge, New Jersey, U.S.A. WILLIAM ANDREW PUBLISHING, LLC Norwich, New York, U.S.A. Copyright © 1999 by Noyes Publications No part of this book may be reproduced or utilized in any form or by any means, elec- tronic or mechanical, including photocopying, recording or by any information storage and retrieval system, without permission in writing from the Publisher. Library of Congress Catalog Card Number: 99-26065 ISBN: 0-8155-1432-8 Printed in the United States Published in the United States of America by Noyes Publications / William Andrew Publishing, LLC Norwich, New York, U.S.A. 10 9 8 7 6 5 4 3 2 1 Library of Congress Cataloging-in-Publication Data Pierson, Hugh O. Handbook of chemical vapor deposition / by Hugh O. Pierson. -- 2nd ed. p. cm. Rev. ed. of: Handbook of chemical vapor deposition (CVD), c1992 Includes bibliographical references. ISBN 0-8155-1432-8 1. Chemical vapor depostion Handbooks, manuals, etc. 2. Vapor -plating Handbook, manuals, etc. I. Pierson, Hugh O. Handbook of chemical vapor deposition (CVD) II. Title. TS695.P52 1999 671.7'35--dc21 99-26065 CIP About the Author Hugh Pierson is presently a private consultant in Chemical Vapor Deposition. He was formerly the head of the Deposition Laboratory at the Sandia National Laboratories and is now retired. Since then, he has been a consultant to the U.S. State Department in South America; Ultramet in Pacoima, California; LOF in Toledo, Ohio; the Gorham Institute in Maine; REI in Whittier, California; TH Goldschmidt AG in Germany; and to many other companies.
    [Show full text]
  • CVD) Developed During My Graduate Study with Professor Gordon at Harvard University
    Chemical Vapor Deposition of Thin Film Materials for Copper Interconnects in Microelectronics A dissertation presented by Yeung Au to The Department of Chemistry and Chemical Biology in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the subject of Chemistry Harvard University Cambridge, Massachusetts May, 2012 © 2012 – Yeung Au All rights reserved. Dissertation Advisor Author Professor Roy G. Gordon Yeung Au Chemical Vapor Deposition of Thin Film Materials for Copper Interconnects in Microelectronics Abstract The packing density of microelectronic devices has increased exponentially over the past four decades. Continuous enhancements in device performance and functionality have been achieved by the introduction of new materials and fabrication techniques. This thesis summarizes the thin film materials and metallization processes by chemical vapor deposition (CVD) developed during my graduate study with Professor Gordon at Harvard University. These materials and processes have the potential to build future generations of microelectronic devices with higher speeds and longer lifetimes. Manganese Silicate Diffusion Barrier: Highly conformal, amorphous and insulating manganese silicate (MnSixOy) layers are formed along the walls of trenches in interconnects by CVD using a manganese amidinate precursor vapor that reacts with the surfaces of the insulators. These MnSixOy layers are excellent barriers to diffusion of copper, oxygen and water. Manganese Capping Layer: A selective CVD manganese capping process strengthens the interface between copper and dielectric insulators to improve the electromigration reliability of the interconnects. High selectivity is achieved by deactivating the insulator surfaces using vapors iii containing reactive methylsilyl groups. Manganese at the Cu/insulator interface greatly increases the strength of adhesion between the copper and the insulator.
    [Show full text]
  • Vacuum Deposition Onto Webs, Films, and Foils This Page Intentionally Left Blank Vacuum Deposition Onto Webs, Films, and Foils
    Vacuum Deposition onto Webs, Films, and Foils This page intentionally left blank Vacuum Deposition onto Webs, Films, and Foils Second Edition Charles A. Bishop AMSTERDAM G BOSTON G HEIDELBERG G LONDON NEW YORK G OXFORD G PARIS G SAN DIEGO SAN FRANCISCO G SINGAPORE G SYDNEY G TOKYO William Andrew is an imprint of Elsevier William Andrew is an imprint of Elsevier 225 Wyman street, Waltham, MA 02451, USA The Boulevard, Langford Lane, Oxford OX5 1GB, UK First edition 2007 Second edition 2011 r 2011 Elsevier Inc. All rights reserved No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the Publisher. Details on how to seek permission, further information about the Publisher’s permissions policies and our arrangements with organizations such as the Copyright Clearance Center and the Copyright Licensing Agency, can be found at our website: www.elsevier.com/permissions. This book and the individual contributions contained in it are protected under copyright by the Publisher (other than as may be noted herein). Notices Knowledge and best practice in this field are constantly changing. As new research and experience broaden our understanding, changes in research methods, professional practices, or medical treatment may become necessary. Practitioners and researchers must always rely on their own experience and knowledge in evaluating and using any information, methods, compounds, or experiments described herein. In using such information or methods they should be mindful of their own safety and the safety of others, including parties for whom they have a professional responsibility.
    [Show full text]
  • Methods for Electroplating Metals on Nonconducting Materials
    U. 3 » DEPARTMENT OF COMMERCE NATIONAL BUREAU OF STANDARDS WASHINGTON 25, D.C. Revised Letter November Circular 1953 LC1013 METHODS FOR ELECTROPLATING METALS ON NONCONDUCTING MATERIALS The following information is based principally on pub- lished papers and not on any extensive experience by this Bureau. The details of the various methods may require modification for specific products. Some knowledge of and experience in electroplating are desirable before attempting to conduct these operations on even a small commercial scale. GENERAL PRINCIPLES It is necessary to render the surface impervious and conducting before electroplating is applied. It is customary to first electrodeposit copper, upon which other metals may then be plated. A coating of clear lacquer is usually applied to the final surface to resist tarnish. RENDERING THE SURFACE IMPERVIOUS Glass and plastics are practically impervious to water. Wood may be rendered impervious by applying at least two coats of a good spar varnish. Plaster and leather articles such as baby shoes may be immersed in melted, paraffin or beeswax, heated to about 212 °F, until the bubbling caused by release of air or moisture nearly ceases. They are then re- moved and allowed to drain and to cool. RENDERING THE SURFACE CONDUCTING 1. Silvering. Glass and plastics are coated with silver by chemical reduction (similar to the silvering of glass mirrors). The solutions and methods are described in NBS Circular 3&9, a copy of which may be purchased for 10 cents (stamps not accepted) from the Superintendent of Documents, Government Printing Office, Washington 25, D. C. 2. Copper or silver powder.
    [Show full text]
  • Improvements in Processing and Stretchability of Super Gas
    IMPROVEMENTS IN PROCESSING AND STRETCHABILITY OF SUPER GAS BARRIER MULTILAYER THIN FILMS A Dissertation by FANGMING XIANG Submitted to the Office of Graduate and Professional Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Chair of Committee, Jaime C. Grunlan Committee Members, Hong Liang Jodie Lutkenhaus Xinghang Zhang Head of Department, Andreas A. Polycarpou May 2015 Major Subject: Mechanical Engineering Copyright 2015 Fangming Xiang ABSTRACT Polymeric materials with gas barrier equivalent to metalized plastics have become increasingly important for food packaging, electronic device encapsulation, and vacuum insulation. Early attempts to develop alternative gas barrier materials have focused on thick (>10 μm) polymer/clay composites produced using physical mixing, but only limited improvement was achieved due to aggregation and random orientation of clay platelets. Layer-by-layer (LbL) assembly is a simple yet powerful bottom-up fabrication technique, which allows assembly of thin films with designed microstructure under ambient conditions. These multilayer thin films have many desirable properties: mechanical flexibility, transparency, and impermeability. This dissertation sought to further improve the processing and properties of high gas barrier thin films produced using LbL assembly. The influence of deposition time on gas barrier of polymer/clay multilayer thin films composed of polyethylenimine (PEI), poly(acrylic acid) (PAA), and clay was investigated. Multilple PEI/PAA bilayers (BL) were deposited between clay layers to construct multilayer assemblies with quadlayer (QL), hexalayer (HL), and octalayer (OL) sequences. Regardless of film structure, polymer/clay multilayer thin films prepared using shorter dipping time were thicker and exhibited better gas barrier than samples prepared using longer dipping time in the first few layers.
    [Show full text]