Sachithanadam / Joshi Silica Aerogel Composites

Novel Fabrication Methods
1. Auflage 2016
ISBN: 978-981-10-0440-7
Verlag: Springer Nature Singapore
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, 149 Seiten

Reihe: Engineering Materials

This book explores the improvement in thermal insulation properties of protein-based silica aerogel composites fabricated by a novel, inexpensive and feasible method. The resulting material exhibits polymeric foam behavior including high compressibility, super-hydrophobic qualities and excellent strain recovery in addition to low thermal conductivity. The fabrication methodologies are explained in great detail and represented in flowcharts for easy reference and understanding. This monograph gives readers a new perspective on composite fabrication using methods other than the traditional ones and explores the endless ways of altering the composition to modify the properties of the silica aerogel composites. Applications for this novel composite are diverse and range from those in the pharmaceutical and aerospace industries to the oil and gas industries.

Dr. Sunil C. Joshi received his Ph.D. degree from Monash University (Australia) for his work on composites manufacturing processes. Prior to that he worked as Scientist at National Aerospace laboratories, Bangalore, India, where he was part of the composite structures group from 1988 to 1994 after completing his M. Tech in Aeronautical Engineering with aircraft structures specialization.
He has been a faculty in the School of Mechanical and Aerospace Engineering, at Nanyang Technological University, Singapore, since 2000, currently serving under Aerospace Engineering cluster with Materials and Structures as the focus area.
His research interests encompass aerogel composites, nano-engineered composites, microwave curing, manufacturing of thick composites, damages in braided and filament wound composites, and hygrothermal effects on composites. He looks into applications of composites for impact resistance, thermal insulation, and acoustic damping.
He is an area editor for an Elsevier Journal and serves as reviewer for a number of international journals. He has more than 120 international journal and conference papers, 1 book, 1 applied patent and 5 book chapters to his publication list.Mahesh Sachithanadam received his Bachelors' Degree in Mechanical Engineering from University of Newcastle, Australia, in 2010, with Class 1 Honors. He worked previously as a Military Expert (Engineer) in the Republic of Singapore Armed Forces (RSAF). He is currently pursuing PhD on aerogel composites under the supervision of Assoc. Prof. Sunil Chandrakant Joshi from the School of Mechanical & Aerospace Engineering, Nanyang Technological University, Singapore.
Mahesh has been working on aerogel composites for his PhD and has presented his work on 'A New Phenomenon of Compressive Strain Recovery in Gelatin-silica Aerogel Composites with SDS', 'Brittle to Ductile Transitions in Silica Aerogel Behaviour with Post Synthesis Binding Treatment' and 'High strain recovery with improved mechanical properties of gelatin-silica aerogel composites post-binding treatment' at various forums. Mahesh also coauthored a pending patent titled 'Compressibility, Strain Recovery and Hydrophobicity in Silica Aerogel Composites' (TD/181/13) with his supervisor. Currently he is compiling his thesis.

Autoren/Hrsg.

Sachithanadam, Mahesh

Joshi, Sunil Chandrakant

Inhaltsverzeichnis

1;Preface;6
2;Contents;7
3;Abbreviations and Symbols;10
4;1 Introduction;12
4.1;1.1 What Is Aerogel???;12
4.2;1.2 How It All Started2026;13
4.3;1.3 Uniqueness of the Book;14
4.4;References;14
5;2 Aerogels Today;16
5.1;2.1 Introduction;16
5.2;2.2 Aerogels Today;16
5.3;2.3 Market Outlook;17
5.4;2.4 Silica Aerogels;18
5.5;2.5 Evolution of Silica Aerogels;19
5.5.1;2.5.1 Formation of Wet Gel;19
5.5.1.1;2.5.1.1 Precursors, Solvents, and Catalysts;20
5.5.2;2.5.2 Aging and Fluid Exchange of Wet Gel;20
5.5.3;2.5.3 Drying;20
5.5.3.1;2.5.3.1 Supercritical Drying (SCD);21
5.5.3.2;2.5.3.2 Ambient Pressure Drying (APD);21
5.5.3.3;2.5.3.3 Freeze Drying (FD);22
5.6;2.6 Concluding Remarks;23
5.7;References;23
6;3 Fabrication Methods;26
6.1;3.1 Introduction;26
6.2;3.2 Silica Aerogel `Hybrid' Composites---Developments and Limitations;26
6.3;3.3 Silica Aerogel Binder Composites;28
6.3.1;3.3.1 Associated Problems;28
6.4;3.4 Surface Chemistry of Silica Aerogel Granules;29
6.5;3.5 Possible Routes of Binder Composite Fabrication;31
6.5.1;3.5.1 Route 1---Resin Binders;31
6.5.2;3.5.2 Route 2---De-Methylation of Hydrophobic Groups;31
6.5.3;3.5.3 Route 3---Water Soluble Materials;32
6.6;3.6 Possible Binder Materials;34
6.6.1;3.6.1 Gelatin;34
6.6.1.1;3.6.1.1 Properties of Gelatin;36
6.6.2;3.6.2 Additives;37
6.6.2.1;3.6.2.1 Sodium Dodecyl Sulfate (SDS);37
6.6.2.2;3.6.2.2 Carbon Nanotubes (CNTs);37
6.6.2.3;3.6.2.3 Functionalized CNTs;38
6.7;3.7 Materials' Property and Data;39
6.8;3.8 Fabrication Methodologies of GSA Composites;40
6.8.1;3.8.1 FM Method;40
6.8.2;3.8.2 FD Method;42
6.9;3.9 Concluding Remarks;43
6.10;References;44
7;4 Microstructural Analysis;47
7.1;4.1 Introduction;47
7.2;4.2 Hypothesis on Binder Concept;47
7.3;4.3 Chemical Analysis of Gelatin Films;48
7.4;4.4 Microstructural Examination of Silica Aerogels and Their Composites;53
7.4.1;4.4.1 SEM/EDX Characterization;53
7.4.2;4.4.2 XPS/ESCA Surface Characterization;56
7.5;4.5 Concluding Remarks;59
7.6;References;59
8;5 A New Phenomenon---Brittle to Ductile Transition;61
8.1;5.1 Introduction;61
8.1.1;5.1.1 Parametric Model;62
8.1.2;5.1.2 Direct Experimental Measurements;65
8.2;5.2 Experimental Setup;65
8.3;5.3 GSA and GSA--SDS Composites (FM Method);67
8.3.1;5.3.1 Compressive Stress--Strain Behavior (FM Composites);67
8.3.2;5.3.2 Unusual Phenomenon---Brittle to Ductile Behavior;69
8.3.3;5.3.3 Influence of SDS on Composite Properties from ANOVA;70
8.3.3.1;5.3.3.1 Statistical Analysis of Measured Data;70
8.3.3.2;5.3.3.2 General Trend of Density;73
8.3.4;5.3.4 Strain Recovery Optimization via Empirical Models;74
8.4;5.4 Validation of Optimal Properties with GSA--SDS Composites;77
8.4.1;5.4.1 Influence of Silica Aerogel Granules on Mechanical Properties of GSA--SDS Composites;79
8.5;5.5 FMWNT-Doped GSA and GSA--SDS Composites (FM);82
8.5.1;5.5.1 Influence of FMWNT on Composites;82
8.5.2;5.5.2 Experimental Result---General Trend of Stress--Strain Curves;83
8.5.3;5.5.3 Empirical Analysis of Various Properties;85
8.5.3.1;5.5.3.1 Strain Recovery;85
8.5.3.2;5.5.3.2 Compressive Strength and Modulus;87
8.6;5.6 Concluding Remarks;88
8.7;Appendix 5A---Failed Specimen Analysis (FM Method);89
8.8;References;89
9;6 Superhydrophobic and Ultralow Thermal Insulation;91
9.1;6.1 Introduction;91
9.1.1;6.1.1 Hydrophobicity;92
9.2;6.2 Thermal Conductivity Measurements;94
9.3;6.3 Operating Temperature of GSA--SDS Composites;97
9.4;6.4 Silica Aerogel Granule Size Distribution;98
9.5;6.5 Thermal Conductivity of Silica Aerogel Granules;99
9.6;6.6 Thermal Conductivity of GSA--SDS Composites;101
9.6.1;6.6.1 Influence of Silica Aerogel Granules on the Thermal Conductivity of GSA--SDS (FD) Composites;103
9.7;6.7 Thermal Conductivity of GSA--SDS/FMWNT Composites;104
9.7.1;6.7.1 Optimization and Validation;107
9.8;6.8 Thermal Transport Phenomenon in GSA--SDS/FMWNT Composites;108
9.9;6.9 Superhydrophobicity of FMWNT doped GSA--SDS Composites;111
9.10;6.10 Concluding Remarks;114
9.11;Appendix 6A---Granule Size Distribution;115
9.12;Appendix 6B---Optimization of Coupled Function;116
9.12.1;Derivation of Optimal Values for Coupled Function of SDS and FMWNT;116
9.12.2;1st Derivation Test;116
9.12.3;2nd Derivation Test;116
9.13;References;117
10;7 Acoustic Performance of Silica Aerogel Composites;119
10.1;7.1 Introduction;119
10.2;7.2 Experimental Procedure;121
10.2.1;7.2.1 Transfer Function Method (2-microphone);121
10.2.2;7.2.2 Inferential Transmission Loss (InTLM);123
10.2.3;7.2.3 Sound Meter Measurements;125
10.3;7.3 Silica Aerogel Granules Optimization;125
10.3.1;7.3.1 Transmission Loss of Silica Aerogel Granules;128
10.4;7.4 Acoustic Performance GSA--SDS Composites and Other Materials;129
10.4.1;7.4.1 GSA--SDS;130
10.4.2;7.4.2 GSA--SDS/FMWNT Composites;135
10.4.3;7.4.3 `InTLM' and Sound Meter;137
10.5;7.5 Comparative Analysis with Other Traditional Materials;138
10.5.1;7.5.1 Acoustic Activity;139
10.6;7.6 Concluding Remarks;140
10.7;References;141
11;Appendix: Useful MATLAB Codes;143
12;Index;145