Self-Healing Nanotextured Vascular Engineering Materials

Preface

Contents

About the Authors

1 Introduction

1.1 Nature-Inspired Biomimetic Self-Healing for Self-sustained Mechanical Properties

1.2 Self-Healing: Extension to Corrosion Protection

1.3 Capsule-Based Approach to Self-Healing

1.3.1 Microcapsules Filled with Healing Agents

1.3.2 Nanoscale Capsules Filled with Healing Agents

1.4 Tube and Channel Networks and Microfibers

1.5 Sacrificial Materials and Shape-Memory Polymers

References

Materials and Fundamental Physicochemical Phenomena

2 Healing Agents Used for Mechanical Recovery in Nanotextured Systems

2.1 Dicyclopentadiene (DCPD) and Grubbs’ Catalyst

2.2 Poly(Dimethyl Siloxane) (PDMS)

2.3 Other Elastomers

2.4 Bisphenol-A-Based Epoxy and Other Types of Epoxy

2.5 Gels

References

3 Macroscopic Observations of Physicochemical Aspects of Self-Healing Phenomena

3.1 Spreading of Released Drops of Healing Agents on Horizontal Surfaces

3.1.1 Experimental Observations

3.1.2 Wetting of Self-Healing Agents on Porous Electrospun NFs

3.1.3 Coalescence of Droplets of Self-Healing Agents on Porous Electrospun NFs

3.1.4 The Hoffman–Voinov–Tanner Law and Droplet Footprint Spreading on Wettable Intact Surfaces and NF Mats

3.1.5 Coalescence of Droplets on NF Mats

3.2 Spreading on Tilted Surfaces

3.3 Filling of Crack Tips

3.3.1 Macroscopic View of Epoxy Release and Hardening

3.3.2 Epoxy-Hardener Reaction Observed in a Macroscopic Crack-Tip-Shaped Mold

3.4 Stitching Cracks and the Corresponding Mechanical Properties

3.4.1 Macroscopic Model of Self-Healing Composite Materials with Embedded Microchannel System

3.4.2 Release and Mixing of Healing Agents

3.4.3 Wettability-Driven Spreading and Polymerization of Healing Agents

3.4.4 Recovery of Mechanical Strength

References

Fabrication Methods

4 Fabrication of Vascular Nanofiber Networks with Encapsulated Self-Healing Agents for Mechanical Recovery

4.1 Electrospinning

4.1.1 Charge Relaxation Time in Electrolytes

4.1.2 Formation of Electrospun Polymer NFs

4.2 Co-electrospinning

4.3 Emulsion Spinning

4.4 Solution Blowing

4.5 Coaxial Solution Blowing

4.6 Emulsion Blowing

4.7 Two- and Three-Dimensional Self-Healing Materials

4.7.1 Two-Dimensional Planar Self-Healing Composites

4.7.2 Three-Dimensional Self-Healing Composites

References

5 Characterization of Self-Healing Phenomena on Micro- and Nanoscale Level

5.1 Visualization

5.2 Spectroscopic Characterization

5.3 Thermal Analysis

References

Mechanical Behavior of Self-Healing Nanotextured Materials

6 Failure, Cracks, Fracture, Fatigue, Delamination, Adhesion, and Cohesion

6.1 Failure Criteria

6.2 Cracks in Brittle Elastic-Plastic Media

6.3 Cracks in Viscoelastic Media

6.4 Fatigue Cracks

6.5 Critical Catastrophic Crack and Subcritical Crack Propagation

6.6 Delamination Cracks

6.7 Adhesion and Cohesion Energy: Stiff Materials

6.8 Adhesion and Cohesion Energy: Soft Materials

References

7 Self-Healing of Mechanical Properties: Evaluation by Tensile Testing

7.1 Tensile Testing: Stiffness Recovery in Composites with Co-electrospun Polyacrylonitrile–DMS Resin Monomer–Curing Agent Nanofibers

7.2 Tensile Testing: Stiffness Recovery in Composites with Solution-Blown PVDF/PEO/Epoxy/Hardener NFs

7.3 Strength Recovery Under Static Fatigue Conditions

7.4 Dynamic Situation: Mode I Crack Propagation

References

8 Self-Healing at Ply Surfaces: Adhesion, Cohesion, and Interfacial Toughening Evaluated Using Blister and Impact Tests

8.1 Blister Testing: Recovery of Adhesion or Cohesion in Composites with Co-electrospun PAN/DMS-Resin/Curing Agent NFs

8.2 Blister Testing: Recovery of Adhesion or Cohesion in Composites with Solution-Blown PVDF/PEO/Epoxy/Hardener NFs

8.3 Double-Cantilever Beam and Bending Tests

8.3.1 Double-Cantilever Beam Test

8.3.2 Bending Test

8.4 Interfacial Toughening Due to NFs: Intrinsic Versus Extrinsic Toughening and Self-Healing Characterized by Impact Testing

8.5 Cumulative Results on Mechanical Recovery of Self-Healing Vascular Materials

8.6 Self-Healing of Three-Dimensional Materials

References

Self-Healing Nanotextured Materials for Corrosion Protection

9 Capsule-Based Self-Healing Approaches for Corrosion Protection

9.1 Electrochemical Fundamentals of Corrosion Cracking of Metals

9.2 Healing Agent-Embedded Capsule-Based Self-Healing

9.3 Modified Healing Agents and Microcapsules

9.4 Corrosion Inhibitor-Embedded Capsule-Based Self-Healing

References

10 Fiber-Based Self-Healing Approaches for Corrosion Protection

10.1 Corrosion Protection Provided by Coatings with Embedded Core-Shell NFs Formed by Co-Electrospinning

10.2 Corrosion Protection Provided by Coatings with Embedded Core-Shell NFs Formed by Emulsion Spinning

References

11 Concluding Remarks and Future Perspectives

11.1 Advantages and Disadvantages of Self-Healing Engineering Materials and Future Research Directions

References

Index