A Fundamental Review of the Relationships between Nanotechnology and Lignocellulosic Biomass - The Nanoscience and Technology of Renewable Biomaterials - page 6

materials and products derived from trees. The Principles of Green Engineering 1 are as

follows (Schmidt 2007):

1. Engineer processes and products holistically, use systems analysis, and integrate envi-
ronmental impact assessment tools.
2. Conserve

and improve natural ecosystems while protecting human health and

well-being.
3. Use life-cycle thinking in all engineering activities.
4. Ensure that all material and energy inputs and outputs are as inherently safe and
benign as possible.
5. Minimize depletion of natural resources.
6. Strive to prevent waste.
7. Develop and apply engineering solutions, while being cognizant of local geography,
aspirations, and cultures.
8. Create engineering solutions beyond current or dominant technologies; improve, inno-
vate, and invent (technologies) to achieve sustainability.
9. Actively engage communities and stakeholders in development of engineering solu-
tions.

As we apply nanotechnologies to the lignocellulosic products industry, we will need to
be cognizant of how the applications of these new technologies adhere to and advance
Green Chemistry and Green Engineering principles.

1.4 Nanotechnology

The ability to see materials at or near atomic dimensions and to measure physical
properties at these scales has enabled the emergence of a discipline now known as
Nanotechnology. At these scales and up to approximately 100 nm unusual properties
are often encountered. In addition many fundamental properties are driven by processes
scaled at the 10s of nm dimension. Many 'natural products' with valuable properties
such as silk, wool, nacre, wood and clay have building blocks that are 1 to 10s of nm
in dimension and owe their valuable properties to these nanometer-scale building blocks
(Roco 2003). Table 1.1 shows a short compilation of some of the key physical properties
and their dimensional dependencies.
Already, there are over 700 nanomaterial-containing products available in the market
place, including coatings, computers, clothing, cosmetics, sports equipment, and medical
devices (Langsner 2006). The estimated global market for nanotechnology enabled
products was approximately US$9.4 billion in 2005, over US$10.5 billion in 2006, and
projected to grow to over US$25 billion by 2011 (Lux Research Inc. 2004, Hullmann
2006, Technology Transfer Center 2007). Nanomaterials - particularly nanoparticles
and nanocomposites - currently account for over 85% of the market. Currently used
nanomaterials include carbon nanotubes, carbon black fillers, nanocatalyst thin films,
nanodimensional additives, and nanoscale sensors.

1 As developed by more than 65 engineers and scientists at the Green Engineering: Defining the Principles Conference,
held in Sandestin, Florida in May 2003.