I. Introduction ................................................................. 554 II. Manufacturing of Nanocomposites ............................ 556

A. Intercalation in 2-D and 3-D Structures ........ 557 B. Use of Preformed Nanoparticles ..................... 558 C. Preparation Routes........................................... 559

In situ

Polymerization ........................ 559 2. Solvent-Assisted Techniques .............. 561

3. Melt Compounding ............................. 561 III. Structure Development and Characterization.......... 567

A. Particle Dispersion ........................................... 567 B. Matrix Polymer (Bulk) ..................................... 569 C. Interphase ......................................................... 571 D. Effects of Processing......................................... 573

IV. Properties and Their Prediction................................. 575 A. Mechanical Response ....................................... 575

1. Stiffness and Ultimate Properties for 2-D Intercalated Nanocomposites...... 575

2. Stiffness and Ultimate Properties of Nanocomposites with Preformed Quasi-Spherical Particles ................... 577

3. Creep and Fatigue Behavior .............. 578 4. Toughness............................................ 580

B. Thermal Behavior............................................. 584 C. Rheological Behavior........................................ 585 D. Barrier Properties ............................................ 586 E. Fire Retardant Properties................................ 587 F. Other Properties ............................................... 589

V. Summary and Outlook................................................ 589 Acknowledgments................................................................. 589 References............................................................................. 590

I. INTRODUCTION

Nanoparticle-modified polymer composites (also termed polymeric nanocomposites, inorganic/organic hybrid materials) have attracted great scientific and technological interest owing to their exceptional physico-mechanical, thermal and other properties achieved at very low nanoparticle content (<5 wt% or <2~3 vol%). Nanoparticle means that the size of the related inorganic filler — at least in one dimension — is on nanometer scale. Note that the size of traditional fillers and reinforcements is in micrometer range (ca. 10 µm and more). Although the term nanocomposite sounds like a current one, nanocomposites have been produced industrially for more than half a century. In this respect attention should be drawn to the rein-

forcement of rubbers by nanometer scale carbon black. In addition, many natural and artificial products can be considered as nanocomposites based on their build-up.