1.  Summarization of nanotech apply in paper making

The main reason for applying nanotechnology solutions is added value. Nanotechnology in papermaking can be applied in several areas. These include:

·         Water based coatings that are non-toxic, smoother and tougher

·         Surfaces that are smoother and have better printability

·         Enhanced sheet properties by adding nanoparticles such as silica

·         Developing grades that are stronger and lighter, use less fibre and are biodegradable

·         Closed looped water reuse with nano-filtration

In traditional paper making, nano-particle-based fillers, substituting for fibre, and combined with lower basis weights, are delivering significant savings to the industry. Also, wet end retention aids are another example of existing nanotechnology.

Nano materials have unique properties (physical, chemical, electrical and optical) which are different from the original material, and they range in size between 1 and 200 nm. Examples of new applications include nanoparticles kaolin pigment, which have improved stiffness over conventional kaolin in coating and surface pigmentation applications.

Research into the application of nanotechnologies for papermaking is in progress in different parts of the world including the US, Canada and Scandinavia. One environmentally-driven shift concerns the elimination of fluorocarbons in coatings, as well as minimizing petroleum-based extruded polymeric films. Water-based barrier coatings in paper and board applications in the food industry have proven successful. These barriers, which are effective against grease, oil and vapour, employ nano-level mineral formulations. Other examples include high filler loading, and using nanoparticle retention aids for high speed paper machines, which increase productivity. Nano sizing to improve surface sizing, and nanoparticles to improve coating hold-out, have improved printing on a wide range of paper grades. Using a silica nanoparticle system, an open sheet structure can be achieved, which is attractive for the packaging of bulk powders such as cement, where paper porosity to air is important.

2.  Nano-materials which commonly used in paper making

    

Nano-materials	Functions
Nano titanium dioxide	Antibacterial；Heat-resistant；Good safety performance
Nano zinc
Nano silica
Nano silver
Nano copper
Nano chromium trioxide	Wear resistance; Water-resistance; Corrosion resistance; Electrostatic shielding; Lower electrostatic effect; Better printability
Nano silica
Nano zinc oxide
Nano ferric oxide
Nano tin dioxide
Nano calcium carbonate	Lower cost; Enhance color fastness; Enhance surface strength and smoothness
Nano titanium dioxide
Nano silica