What is Nanotechnology? ::
Nanotechnology—how big or small?
If a definition of technology is "the application of science and scientific knowledge for industrial or commercial objectives," then in its most simplistic form, nanotechnology might be specifically defined as "the application of science and scientific knowledge, at the nanoscale, for industrial or commercial objectives." In order to understand the size of material/matter involved at the nanoscale level, one needs to trace down the units of measurement, commencing with an ant (at the milliscale) and ending at the very bottom, at the nanoscale. The nanoscale is far from the smallest unit of measurement—it is however the smallest scale at which matter can be manipulated. Figure 1 illustrates where the nanoscale fits in with relation to other scales.
Figure 1 :: The size of nanotechnology
Nanotechnology—the manufacture
In terms of techniques for manufacturing nanoscale materials, there are two different approaches, bottom up and top down. Figures 2 and 3 give examples of each approach.
Top-down refers to making nanoscale structures by machining and etching techniques, whereas bottom-up, or "molecular nanotechnology," applies to building organic and inorganic structures atom-by-atom, or molecule-by-molecule.
| Lithography | Cutting / Etching / Grinding |  |
|---|---|---|
| Electronic devices; Chip masks | Precision engineered surfaces | |
Quantum well lasers; Computer Chips; |
High quality optical mirrors. |
| Chemical Synthesis | Self Assembly | Positional Assembly | |
|---|---|---|---|
| Particle; molecules | Crystals; films; tubes | Experimental atomic or molecular devices | |
| Cosmetics; Fuel additives | Displays | ||
| Main applications: Structural; Skincare; ICT; Biotech; Instruments; Sensors; Environmental filtration | |||
Nanotechnology—the applications
Many believe that the scientist K. Eric Drexler popularised the word nanotechnology in the 1980's with his fictional writings on the construction of machines built on the nanoscale—machines such as miniature submarines capable of being transported through the human body. However these have not been the only application for nanotechnology, because the nanoscience behind the technology is now recognised as having "general purpose" potential. When the technology is essentially fully mature, the manufacture of products from nano-scale materials will significantly impact virtually all industries and all areas of society. Yet with all the hypotheses and press releases covering nano-machines, nanorobots (nanobots) and suchlike, it is not surprising that nanotechnology is usually associated with science fiction scenarios—the reality is far from this. The manufacturing techniques and manipulation tools used in nanotechnology are already deemed suitable for the improvement and development of molecular medicine, biotechnology, advanced materials and other indirect applications relating to the environment (i.e. energy and pollution reduction). Currently the general trend is towards the use of nanotechnology within the area information and communication technology (ICT), especially focused upon the miniaturisation of electronic systems.
For many scientists, working with materials at the nanoscale is nothing unusual. Chemists and physicists have been analysing and manipulating (combining/splitting) materials at the nanoscale for decades. Recent developments in the tools used to characterise and observe nanoscale materials have led to an increased understanding of their behaviour and properties. Such tools have been used to investigate some of the nanoscale materials that will be used in the SustainPack project i.e. nanoclays and nanofibrils. Details and potential applications for these materials can be seen in Figure 4.
| Description | Applications | |
|---|---|---|
| Nanoclay | ~1nm thick sheet like minerals, which naturally form in stacks and can be split apart into the individual platelets | The split (exfoliated) stacks can be blended with renewable polymers to produce plastics with enhanced properties |
| Nanofibril | 20-200nm diameter chains of cellulose molecules that form the cellulose fibres found in paper | The cellulose chains can be blended with other materials to give enhanced properties |
Nanotechnology—the risks
As with any developing technology, there will be actual and perceived risks and associated fear so there is an urgent requirement to constructively and proactively debate these now, rather than wait until polarised views have developed—which are likely to damage any further advances in the technology. It seems likely that although there is much political support for nanotechnology, a repeat performance of the handling of Genetically Modified Organisms (GMOs) use in agriculture—should be avoided at any cost. Therefore, thorough risk assessments of the advancements in nanotechnology should almost be as important as the technology itself. For example, it is envisaged that it will be important to assess whole lifecycles via Life Cycle Analysis (LCA) tools, in order to evaluate the net benefits for environmental improvements. Such evaluations will be required to ensure there is not an increase in burden further down the supply chain, in disposal etc.
The technical challenges should by no means be underestimated. They comprise the following:
- Scaling up from lab to industrial scale
- Understanding the properties involved with nano materials
- Converting the science into application
- Regulating, standardising, classifying and risk managing
Summary
Developments in nanotechnology are some of the most important scientifc developments in recent years, with many industries, including the packaging industry being set to benefit. In parallel there is now also a need for informed and rational debate to ensure those involved, apply nanotechnology safely to their products. The SustainPack project seeks to identify and advance the application of nanotechnology to unlock these benefits.
Henry Goodband, Consultant, Pira Consulting
This article first appeared in the Sustainpack Newsletter
