TABLE OF CONTENTS Polymer nanocomposites (PNs) consist of a polymeric material (e.g., thermoplastics, thermosets, or elastomers) and a reinforcing nanoscale material (nanoparticle). The nanoparticle has at least one dimension in nanometer scale. Polymer nanocomposites show major improvements in mechanical properties, gas barrier properties, thermal stability, fire retardancy, and other areas. There are many factors that affect the polymer nanocomposite properties:
Synthesis methods such as melt compounding, solvent blending, in-situ polymerization, and emulsion polymerization
Polymer nanocomposite morphology
Types of nanoparticles and their surface treatments
Polymer matrix such as crystallinity, molecular weight, polymer chemistry, and whether thermoplastic or thermosetting
Understanding property improvement related to PN properties is a very complex matter. Table 2.1 shows several benefits and disadvantages when nanoparticles are incorporated into the polymer matrix.
| Improved properties | Disadvantages |
|---|---|
| ? Mechanical properties (tensile strength, stiffness, toughness) | ? Viscosity increase (limits processability) |
| ? Gas barrier | ? Dispersion difficulties |
| ? Synergistic flame retardant additive | ? Optical issues |
| ? Dimensional stability | ? Sedimentation |
| ? Thermal expansion | ? Black color when different carbon containing nanoparticles are used |
| ? Thermal conductivity | |
| ? Ablation resistance | |
| ? Chemical resistance | |
| ? Reinforcement |
There are different types of commercially available nanoparticles that can be incorporated into the polymer matrix to form polymer nanocomposites. Depending on the application, the researcher must determine the type of nanoparticle needed to provide the desired effect. A brief discussion will include the...
