Zinc oxide whiskers properties

Zinc oxide whiskers possess the following attractive physical properties ... 

Good isotropy. The composites made with zinc oxide whiskers have good isotropic mechanical, electrical, and optical properties because of the isotropic structure and properties of zinc oxide whiskers. 

Table 3.5 Physical and Chemical Properties of Zinc Oxide Whiskers... 

Ultraviolet absorption. Zinc oxide whiskers have obvious ultraviolet absorption properties, which could be used to improve the aging resistance of polymers. 

High density. Zinc oxide whiskers can be used to make composites with sound insulation, shock absorption, and vibration resistance properties because of their high relative density (5.78 g/cm ). 

Like other acicular whiskers, general acicular zinc oxide whiskers are mainly used as reinforcing agents in composites tetragonal acicular ZnO whiskers are also used to prepare functional composites because of their unique structure. They are employed to improve some properties of composites, such as tensile strength, flexure resistance, wear resistance at room temperature, as well as chemical and dimensional stability at high temperature. 

When polygonal needle-like zinc oxide whiskers are added to matrix resin, adjacent needles overlap with each other and form a conductive path, which makes the transmission of charge possible, gives electrical conductivity to material, and also gives the polymer material a certain antistatic property. 

He found that zinc oxide whiskers can effectively improve the conductive property of PP resin. When the whisker volume fraction reaches 3%, the resistivity of the material decreases to below 10 Q cm, which is seven orders of magnitude lower than the resistivity of a pure PP matrix, whose resistivity is 10 Q cm and could meet the requirement of a general antistatic material. Wan and Jin put zinc oxide whiskers into an epoxy resin and obtained the same findings. Zhou et al. believed that there are three kinds of conductive mechanisms in the system network conduction, tunnel effect, and point discharge effect. 

Abstract Biodegradable thermoplastic materials offer great potential to be used in food packaging or biomedical industry. In this chapter we will present a review of the research done on starch and starch nanocomposites. In the case of nanocomposites based on starch, special attention will be given to the influence of starch nanoparticles, cellulose whiskers, zinc oxide nanorods, antioxidants, and antimicrobial inclusion on the physicochemical properties of the materials. The discussion will be focused on structural, mechanical, and barrel properties as well as on degradation, antibacterial and antioxidant activities. Finally, we will discuss our perspectives on how future research should be oriented to contribute in the substitution of synthetic materials with new econanocomposites. 

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