Progress in Adhesion and Adhesives Scrivener Publishing 100 Cummings Center, Suite 541J Beverly, MA 01915-6106 Publishers at Scrivener Martin Scrivener ([email protected]) Phillip Carmical ([email protected]) Progress in Adhesion and Adhesives Volume 4 Edited by K.L. Mittal This edition first published 2019 by John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, USA and Scrivener Publishing LLC, 100 Cummings Center, Suite 541J, Beverly, MA 01915, USA © 2019 Scrivener Publishing LLC For more information about Scrivener publications please visit www.scrivenerpublishing.com. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or other- wise, except as permitted by law. Advice on how to obtain permission to reuse material from this title is available at http://www.wiley.com/go/permissions. 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Mittal Cover design by Russell Richardson Set in size of 10pt and Minion Pro by Exeter Premedia Services Private Ltd., Chennai, India Printed in the USA 10 9 8 7 6 5 4 3 2 1 Contents Preface xiii 1 Adhesion Phenomena Pertaining to Thermal Interface Materials and Solder Interconnects in Microelectronic Packaging: A Critical Review 1 Dinesh P R Thanu, Aravindha Antoniswamy, Roozbeh Danaei and Manish Keswani 1.1 Introduction 2 1.2 Polymer Thermal Interface Material -Metal Interface Adhesion Phenomena 3 1.2.1 Basics of Thermal Interface Material Adhesion 3 1.2.2 Current Status of Thermal Interface Materials and their Bonding Mechanisms 5 1.2.3 Chemical Bonding 6 1.2.4 Mechanical Interlocking 12 1.2.5 Weak Boundary Layer 14 1.3 Ball Grid Array Solder Attach Adhesion Phenomena 14 1.3.1 Solder Alloy Selection 15 1.3.2 Flux Selection 18 1.4 Summary 19 Nomenclature 20 References 21 2 Influence of Silicon-Containing Compounds on Adhesives for and Adhesion to Wood and Lignocellulosic Materials: A Critical Review 25 Marko Petricˇ 2.1 Introduction 26 2.2 An Overview of Compounds and Natural Minerals Containing the Element Si, which are the Most Relevant in the Science and Technology of Lignocellulosics 29 2.2.1 Silica – SiO 29 2 2.2.2 Silicates and Clay 30 2.2.3 Silicones 32 2.2.4 Silanes and Silsesquioxanes 33 2.3 Si-containing Compounds in Adhesives and in Lignocellulosic Substrates and their Influence on the Performance of Adhesive Bonds 35 v vi Contents 2.3.1 Compounds of Silicon in Adhesives 35 2.3.1.1 Inorganic Compounds of Si (Silica, Silicates, Clay, and Other Inorganic Compounds) 35 2.3.1.2 Organosilicon Compounds in Adhesives 40 2.3.2 Silicon-containing Compounds in Lignocellulosics with Regard to the Properties of Adhesive Bonds 42 2.3.3 Influence of Si in Coatings or in Lignocellulosic Substrates with Regard to Coatings Adhesion to the Substrates 44 2.4 Interactions of the Si Compounds with Lignocellulosics 46 2.4.1 Interactions with Silica 46 2.4.2 Interactions with Silicates 48 2.4.3 Interactions with Silicones 49 2.4.4 Interactions with Organosilicon Compounds and Coupling Agents 50 2.4.4.1 Interactions with Organosilicon Compounds 50 2.4.4.2 Coupling Agents 52 2.5 Wood- and Lignocellulose-based Composites Containing Si Compounds 57 2.5.1 Composites Containing Silica 57 2.5.2 Composites Containing Silicates and Clay 59 2.5.3 Composites Containing Silicones 60 2.5.4 Composites with Organosilicon Compounds 61 2.6 Summary and General Remarks 64 2.7 Acknowledgments 65 References 65 3 Recent Advances in Adhesively Bonded Lap Joints Having Bi-Adhesive and Modulus-Graded Bondlines: A Critical Review 77 Özkan Öz and Halil Özer 3.1 Introduction 77 3.2 B i-adhesive Joints 80 3.2.1 Numerical and Analytical Studies 80 3.2.2 Experimental Studies 84 3.3 Modulus-Graded Bondline 88 3.3.1 Numerical and Analytical Studies 88 3.3.2 Experimental Studies 91 3.4 Summary 94 Acknowledgement 94 Nomenclature 94 References 94 4 Adhesion between Compounded Elastomers: A Critical Review 99 K. Dinesh Kumar, M.S. Satyanarayana, Ganesh C. Basak and Anil K. Bhowmick 4.1 Introduction 100 4.2 Co-crosslinking 101 Contents vii 4.2.1 Adhesion Between Unvulcanized Rubber (Filled with Crosslinking Agents) and Unvulcanized Rubber (Filled with Crosslinking Agents) by Co-crosslinking 104 4.2.2 Adhesion Between Partially Vulcanized Rubber (Filled with Crosslinking Agents) and Partially Vulcanized Rubber (Filled with Crosslinking Agents) by Co-crosslinking 118 4.3 Adhesion Between Vulcanized Rubber and Unvulcanized Rubber or Partially Vulcanized Rubber 138 4.3.1 Adhesion between Vulcanized Rubber and Unvulcanized Rubber (Filled with Crosslinking Agents) 140 4.3.2 Adhesion between Vulcanized Rubber and Partially Vulcanized Rubber (Filled with Crosslinking Agents) 164 4.4 Adhesion Between Vulcanized Rubber and Vulcanized Rubber 166 4.5 Summary 184 Acknowledgements 186 List of Symbols 186 List of Abbreviations 187 References 189 5 Contact Angle Measurements and Applications in Pharmaceuticals and Foods: A Critical Review 193 Davide Rossi, Paola Pittia and Nicola Realdon 5.1 Introduction 194 5.1.1 Prospects 199 5.2 Contact Angle Measurements in Pharmaceutical Field 200 5.2.1 Pharmaceutical Powders 200 5.2.2 Solvents for Pharmaceutical Use 211 5.2.3 Injectable Solutions for Parenteral Use 218 5.3 Contact Angle Measurements in Foods 222 5.3.1 Solid Foods 222 5.3.2 Liquid Foods and Beverages 231 5.3.3 Food Packaging 234 5.4 Summary 236 Acknowledgement 236 References 237 6 The Formation Processes of Functional Groups at Polyolefin Surfaces on Exposure to Oxygen or Ammonia Plasma: A Critical Review 241 Jörg Friedrich 6.1 Introduction 242 6.1.1 Reasons for Polyolefin Surface Functionalization 242 6.1.2 Energetic Considerations, Thermodynamics and Probability of Reactions 245 6.1.3 Processes on Molecular Level at Polyolefin Surface 249 6.2 Oxygen Plasma Treatment 254 viii Contents 6.2.1 Formation of O Functional Groups at Polyolefin Surfaces on Exposure to Oxygen Plasma 254 6.2.2 Kinetics of Polyolefin Oxidation – Dependence on Parameters 260 6.2.3 Influence of Type of Plasma Gas 262 6.2.4 Influence of Polymer Composition 263 6.2.5 Auto-Oxidation 265 6.2.6 Oxidation by Exposure to Noble Gas Plasmas 267 6.2.7 Generation of OH Groups on the Surface of Polyolefins by Deposition of a Thin Layer of Poly(allyl alcohol) Plasma Polymer 269 6.3 Ammonia Plasma for Introduction of NH Groups onto 2 Polyolefin Surfaces 272 6.3.1 Production of Primary Amino Groups on Exposure to Plasma 274 6.3.2 Thermodynamic Aspects 275 6.3.3 Ammonia Plasma 277 6.3.4 Formation of Functional Groups on Exposure to NH Plasma 278 3 6.3.5 Kinetics of N and NH Introduction on Exposure 2 to Ammonia or Nitrogen-Hydrogen Plasmas 280 6.3.6 Side-Reactions at Polyolefin Surfaces on Exposure to NH 3 Plasma 283 6.3.6.1 Hydrogenation and Dehydrogenation 284 6.3.6.2 Post-Plasma Oxidation 286 6.3.6.3 Nitrile Formation 286 6.3.7 NH Groups via Plasma Polymerization of Allylamine and 2 Other N-Precursors 290 6.3.8 Attempts to Increase the Concentration of NH 2 Groups by Addition of Ammonia to Allylamine Plasma Polymerization 294 6.3.9 Significant Side-Reactions During and After Plasma Polymerization of Allylamine 294 6.4 Discussion 297 6.5 Summary 303 Acknowledgement 304 References 304 7 Surface Free Energy Determination of Powders and Particles with Pharmaceutical Applications: A Critical Review 315 Frank M. Etzler and Douglas Gardner 7.1 Introduction 315 7.2 Surface Thermodynamic Quantities of Pure Materials 316 7.3 Contact Angle Methods 320 7.3.1 The Zisman Method 320 Contents ix 7.3.2 The van Oss, Chaudhury and Good Method 320 7.3.2.1 Methods for Calculating the van Oss, Chaudhury and Good Parameters 324 7.3.3 The Chang – Chen Method 325 7.4 Determination of Surface Free Energy using IGC and AFM 326 7.4.1 Application of the Fowkes Method to IGC Data 326 7.4.2 Application of the van Oss, Chaudhury and Good Method to IGC Data 328 7.4.3 Application of the Chang-Chen Model to IGC Data 329 7.4.4 AFM Methods 329 7.5 Characterizing Surface Properties by Inverse Gas Chromatography 331 7.5.1 IGC Measurements - Experimental Considerations 332 7.5.2 Finite Dilution IGC 339 7.6 Pharmaceutical Applications 340 7.6.1 Surface Free Energy and Crystal Planes 340 7.6.2 Compaction of Tablets 341 7.6.3 Effects of Processing on Surface Free Energy 342 7.6.4 Performance of Dry Powder Inhalers 344 7.6.5 Powder Flow 345 7.7 Summary 346 References 347 8 Understanding Wood Bonds–Going Beyond What Meets the Eye: A Critical Review 353 Christopher G. Hunt, Charles R. Frihart, Manfred Dunky and Anti Rohumaa 8.1 Introduction: Macroscopic Knowledge for Successful Adhesive Bonding of Wood 353 8.2 Bond Formation (Developing Adhesion) 356 8.2.1 Influence of Wood Structure on Bonding 356 8.2.2 Influence of Wood Surface Quality on Bonding 360 8.2.2.1 Mechanical Damage at the Wood Surface 361 8.2.2.2 Surface Chemistry Barriers to Bonding 365 8.2.3 Adhesive Penetration 367 8.2.3.1 Void Penetration (Bulk Flow) 368 8.2.3.2 Cell Wall Penetration (Infiltration) 370 8.2.4 Adhesive Properties that Influence Void and Cell Wall Penetration 373 8.3 Properties of Adhesive-Wood Assemblies 375 8.3.1 Zones in a Wood Bond 375 8.3.2 How Adhesives Accommodate Wood Swelling 376 8.3.3 Two Classes of Adhesives 377 8.3.4 Methods for Determining Void and Cell Wall Penetration 379