Zinc Oxide for Materials Science and Coating Applications Using Nanomaterials from Nanophase Technologies Corporation

Topics Covered

Integrated Family of Technologies
     Wood Preservation
     Marine Antifouling
     Textile Fibers
     UV-Attenuating Coatings
     Permanent Coatings
     Thermoplastics
Products, Data and Specifications
Typical Properties
Zinc Oxide Nanopowders
     NanoTek® Zinc Oxide 1701
     NanoTek® Zinc Oxide C1 1716
     NanoTek® Zinc Oxide C2 EXP 1726
Zinc Oxide Dispersions
NanoShield® ZN-2000 Series Zinc Oxide Dispersions for Paints
     NanoShield® ZN-2000, 50wt% EXP 1754
     NanoShield® ZN-2001, 50wt% EXP 1757
NanoShield® ZN-3000 Series Zinc Oxide Dispersions for Textile Coatings
     NanoShield® ZN-3008C, 50wt% EXP 4023
     NanoShield® ZN-3010, 50wt% EXP 1769
     NanoShield® ZN-3014A, 50wt% EXP 4022
NanoShield® ZN-5000 Series Zinc Oxide Dispersions for Curing Catalyst Applications
     NanoShield® ZN-5060, 50wt% EXP 4024
Organic Borne Zinc Oxide Dispersions for Paints
     NanoTek® Z1102PMA, 50wt% EXP 1707

Integrated Family of Technologies

As a leader in the field of nanomaterials technologies, Nanophase has evolved from solely a producer of nanoparticles into an integrator of commercially scaled nanomaterial technologies focused on market and customer applications. Nanophase Technologies Corporation manufactures a variety of nanocrystalline powders in commercial quantities. The nanocrystalline metal oxides typically have a mean particle size less than 100 nm, are non-porous single crystals, have defined surface chemistry, and are chemically pure. Further modification of these materials often involves vapor-phase coating to prepare a surface-modified dry powder, or liquid phase processing to prepare a dispersion that is compatible with the application. Nanophase’s family of integrated technologies economically produces nanocrystalline materials and then nanoengineers those materials to fit customer’s needs.

Figure 1. Nanophase development process

Nanophase’s development process is designed to produce the most advantageous nanomaterials solution for an application. The foundation technologies are the patented Physical Vapor Synthesis (PVS) process and patent pending NanoArc® Synthesis (NAS) process. These processes use plasma energy to produce pure, non-agglomerated, non-porous, single-phase metal and mixed metal oxide nanoparticles at annual capacities measured in tens of thousands of kilograms per reactor. Nanoparticle size and surface chemistry can be tailored for applications as the nanomaterial is produced.

Wood Preservation

Due to the small size of the nanomaterials, penetration into a porous surface rather than simple surface adhesion can be achieved. With the discontinuation of CCA wood preservation materials for residential uses by the end of 2003, the wood industry is eagerly searching for cost-effective long-lasting anti-microbial products that will allow wood to perform well in outdoor applications. New formulations are usually reported as being more health-friendly and environmental-friendly, but longevity of performance is often missing. The incorporation of NanoTek® products, including zinc oxide, doped zinc oxides into the wood preservation formula helps to provide the required longevity of performance.

Marine Antifouling

Due to the small size of the nanomaterials, the particles are held in the coating lattice and are not readily leached out of the coating by the marine environment, while slowly releasing ions to help provide longer-term anti-fouling character. By the end of 2003, tributyl tin compounds will no longer be approved for use in marine antifouling coatings by the EPA. The need for longevity of antimicrobial activity in marine environments has been recognized, and is not fully addressed using only combinations of organic biocides and copper oxide. NanoArc® copper oxide or doped zinc oxides can reside permanently in marine coating formulations and can increase the lifetime of the antimicrobial activity, meaning that cleaning and re-application cycles can be extended.

Textile Fibers

Nanoparticles have been incorporated into products such as nylon, polypropylene and other polymers to provide long-term antimicrobial character even in harsh environments and after extensive thermal cycling. The need for minimizing or eliminating microbial growth on a variety of textile-based substrates has become a major topic of discussion in numerous industries, including healthcare, home furnishings, filtration and apparel, among others. NanoTek® zinc oxide or doped zinc oxides, due to the small particle size, can be readily incorporated into synthetic fibers such as Nylon prior to extrusion through spinnerets to impart antimicrobial activity with minimal effects on color and clarity, surface gloss, physical properties and melt flow properties. NanoTek® products may also be incorporated into coatings that can be applied to staple fibers to impart antimicrobial activity. Such applications include carpet fibers, water filters of various types, fabrics for use in healthcare facilities and various institutions, activewear and other apparel, home furnishings and a variety of non-woven applications including the transportation and bedding industries. Zinc oxide is FDA approved for skin contact applications and NanoTek® zinc oxide is produced under cGMP conditions and is approved as an active ingredient for personal care products.

UV-Attenuating Coatings

The incorporation of nanomaterials in surface coatings can provide long-term protection from harmful UV radiation in harsh environments without significantly effecting optical clarity, gloss, color or physical properties. Degradation of substrates through exposure to ultraviolet light is an old problem, but now there is a new and permanent solution. Whether the substrate is metal (automotive clear-coats), glass (windows and architectural glazing) or polymeric (plastic sheets and building products), UV attenuation may be critical to the long-term performance of the substrate or items that the substrate protects. Incorporation of NanoDur® zinc oxide or doped zinc oxides into clear surface coatings can help to attenuate unwanted UV light without significantly sacrificing clarity, gloss or physical properties. Additionally, the NanoDur® products will not wear out over time as organic UV absorbers do, and they can withstand high temperatures and harsh conditions during processing without being deactivated. The NanoDur® products can also be surface treated through proprietary technology to ensure compatibility with a variety of coating systems.

Permanent Coatings

Long-term antimicrobial activity can be imparted in many coating formulations through the incorporation of nanomaterials. The desire for permanent coatings to impart long-term antimicrobial or bacteria-stat properties to coated products has been expressed in a variety of industries, including healthcare, industrial and institutional cleaning, food processing, food service, and general paints and coatings. NanoTek® zinc oxide or doped zinc oxides can be fully dispersed into a wide variety of coating formulations, including urethanes, acrylics and vinyl acetates and have shown utility in UV curable and thermosetting coatings as well as in water-based coating systems.

Thermoplastics

Long-term antimicrobial needs in various plastic, rubber and composite materials have been increasing in recent years. Nanomaterials can provide cost-effective longevity of activity even in harsh environments and after significant thermal history, separating them from the more unstable organic biocides. NanoTek® zinc oxide or doped zinc oxides can be fully dispersed into thermoplastic product formulations that are subsequently fabricated via injection molding, extrusion, blow molding, thermoforming or other typical plastic fabrication techniques. Antimicrobial activities are imparted to the article while the small particle size results in minimal effects on color, clarity, surface gloss, physical properties and melt flow properties of the finished product. Applications for antimicrobial plastic parts include children’s toys, refrigerator liners and other appliance parts, interior and exterior wall coverings, adhesives, caulks and sealants and food processing and food service equipment. Zinc oxide is FDA approved for skin contact applications and NanoTek® zinc oxide is produced under cGMP conditions and is approved as an active ingredient for personal care products.

Products, Data and Specifications

Figure 2. NanoTek® Zinc Oxide

Typical Properties

  • ZnO, Purity = 99+%
  • APS 60 nm (determined from SSA)
  • SSA = 18 m2/g (BET)
  • Appearance = White powder
  • Bulk Density = 0.25 g/cc
  • True Density = 5.6 g/cc
  • Morphology = Elongated
  • Crystal Phase = Zincite (hexagonal)

Zinc Oxide Nanopowders

NanoTek® Zinc Oxide 1701

NanoTek® Zinc Oxide, due to the small particle size, can provide UV protection and antimicrobial properties while maintaining a high level of transparency in coatings, polymers, caulks, adhesives and other resin systems.

NanoTek® Zinc Oxide C1 1716

NanoTek® Zinc Oxide C1 has a hydrophobic, nonpolar coating to aid dispersing in organic systems.

NanoTek® Zinc Oxide C2 EXP 1726

NanoTek® Zinc Oxide C2 has an oleophilic, polar coating to aid dispersing in organic systems.

Nanophase has worked diligently for years to develop expertise in dispersing nanomaterials in water, polar organics and non-polar organics.  We offer most of our products in one or more standard dispersions.  We also offer the service of dispersing a nanomaterial in the bulk medium of your choice as long as it is of low viscosity, non toxic, and has a flash point greater than 100°F.

Zinc Oxide Dispersions

NanoShield® ZN-2000 Series Zinc Oxide Dispersions for Paints

NanoShield® ZN-2000, 50wt% EXP 1754

Water borne zinc oxide dispersion is suitable for incorporation in water compatible coatings to improve UV stability and protect against mold, mildew and fungal growth.

NanoShield® ZN-2001, 50wt% EXP 1757

Water borne zinc oxide dispersion is suitable for incorporation in water compatible coatings.  Similar to ZN-2000, but is formulated with rheology modifier to reduce the tendency for gravimetric settling during storage.

NanoShield® ZN-3000 Series Zinc Oxide Dispersions for Textile Coatings

NanoShield® ZN-3008C, 50wt% EXP 4023

NanoShield® ZN-3008C is a cationic dispersion of zinc oxide in water designed to be incorporated in coatings applied to a fabric or non-woven substrates.  Zinc oxide is generally used to provide UVa and UVb blocking, as well as anti-reddening and anti-inflammatory skin effects, antimicrobial activity, and odor control.

NanoShield® ZN-3010, 50wt% EXP 1769

NanoShield® ZN-3010 is a non-ionic dispersion of zinc oxide in water designed to be incorporated in coatings applied to a fabric or non-woven substrates.  Zinc oxide is generally used to provide UVa and UVb blocking, as well as anti-reddening and anti-inflammatory skin effects, antimicrobial activity, and odor control.

NanoShield® ZN-3014A, 50wt% EXP 4022

NanoShield® ZN-3014A is an anionic dispersion of zinc oxide in water designed to be incorporated in coatings applied to a fabric or non-woven substrates.  Zinc oxide is generally used to provide UVa and UVb blocking, as well as anti-reddening and anti-inflammatory skin effects, antimicrobial activity, and odor control.

NanoShield® ZN-5000 Series Zinc Oxide Dispersions for Curing Catalyst Applications

NanoShield® ZN-5060, 50wt% EXP 4024

Water borne zinc oxide dispersion is suitable for curing or cross linking of both natural and synthetic latex polymers.

Organic Borne Zinc Oxide Dispersions for Paints

NanoTek® Z1102PMA, 50wt% EXP 1707

Zinc oxide dispersion in Dowanol PMA is suitable for incorporation in a wide variety of coatings formulations to improve UV stability and protect against mold, mildew and fungal growth.

Source: Nanophase

For more information on this source please visit Nanophase

Date Added: Sep 14, 2006 | Updated: Jun 11, 2013
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