Multi-Functional Materials

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Problem or Challenge

Living systems tend to use materials for multiple functions, whereas we enlist chemistry to develop new materials. For example, a candy wrapper may use up to seven layers of different materials to protect and advertise the product, while "insect cuticle does all this in one material - a composite of polysaccharides whose functions are achieved by altering the shape of the polymers, their alignment, and how they are bonded together." [Benyus, Baumeister]

Multi-functionality in materials is related to structure (organization of the material), as well as information (usage, transformation or regulation). It is primarily found at the level of tissue, organ or organism. At significantly smaller scales, the structural properties disappear, while at much larger scales, the impact of material structure is outweighed by other factors.

If multi-functional materials are of clear evolutionary value to most living things, why have we taken the path of ever-greater proliferation of new substances? The answer may lie in energy. Vincent estimates that "... in technology, the manipulation of energy can account for up to 70% of the solutions to technical problems, whereas in biology energy never figures more than 5% of the time." Solar energy is powerful, but diffuse. When concentrated, sunlight quickly reaches temperatures where protein coagulates. Energy may be the most constrained resource on Earth. "Two problems faced all pre-industrial economies in regard to energy: amount and concentration." [Diamond quoting Goldstone] Our ability to tap fossil fuels has allowed us to deploy energy when and where we need it, in the quantities we require.

Most organisms are limited to using carbon, hydrogen, oxygen and nitrogen as the key building blocks (along with calcium and other trace elements), arranged in a relatively small number of compounds. Fossil fuels allow us to invent new materials that are both energy intensive and energy resistant, further feeding our ability to escape the limits imposed on other organisms. Vincent writes: "In technology we are outside the system. We destroy the information in the material (e.g. by processing, melting etc) then impose a new set of information (flow, moulding, casting) in order to end up with a product. This is making. In biology we are inside the system (at least the thing whose shape is being developed is inside the system) and the general scheme is to USE the information to generate the shapes / functions. This is becoming."

Therefore

We should analyze and utilize the inherent structural properties of materials. An example is the JANO Dual Bike designed by Roland Kaufmann. Kaufmann discovered that wood is significantly stiffer than fiberglass or even Kevlar/epoxy composites. By using wood veneer, Kaufmann was able mold wood into shapes that combined lateral stiffness with the shock absorption of carbon fiber and the responsiveness of steel.

Vincent has proposed the challenge "... what materials processing techniques there are in physics/chemistry/engineering which use and preserve the information at the molecular level. In biology this would be the order of amino acids and the secondary, tertiary, quarternary . . . structures which they drive. In engineering it would be LB films, liquid crystals/thixotropy, followed by electrospinning, spinning, RP, etc . . . How much engineering can we do using only molecular rearrangements? Can we go all the way from nm to m without raising the temperature above (say) 100C?"

Kay emphasizes the importance of considering the quality of energy, not just the quantity. By fully utilizing the structure of materials, we are similarly emphasizing the qualities of material and the embedded, high quality information. <Kay describes how mature ecosystems dissipate and degrade both the quantity of energy as well as its quality - "all processes are performed reversibly and all the available work (exergy) is extracted from the energy" (p. 26). Is there a comparable concept of effective use of the quality of materials?>

Retaining the structure of materials also increases the end-of-life value of those materials. The low value of 'waste' leads to recycling or 'down-cycling', instead of considering 'waste as food'.

But

Few tools exist to analyze quality measures of material flows. Our ability to mimic the benign manufacturing methods of organisms is also limited.

See Also

Working with the inherent structure and quality of materials may significant reduce the amount of energy we consume. The Conducive to Life pattern suggests that lower energy consumption may trigger a 'virtuous cycle' by reducing the need to invest energy in control systems.

Applications

JANO Dual Bike

Roland Kaufmann discovered that wood is significantly stiffer than fiberglass or even Kevlar/epoxy composites. By using wood veneer, Kaufmann was able mold wood into shapes that combined lateral stiffness with the shock absorption of carbon fiber and the responsiveness of steel.

Miscellaneous Ideas

• multi-functionality could be considered as striving to achieve 'multiple goods' (wind power installations in rural USA improves the vitality of the community by generating employment and encouraging local industry, it improves US energy security, and it helps the environment)
• conservation of quality? extending the concepts of Availability, Exergy, the Second Law and all that....... to materials might yield insights applicable to designers
• catalog of material properties across various stages of material lifecycle?
• matching quality of materials to the requirements? (similar to using solar energy for heating, both forms of low-quality energy)

Relationship to Systems Thinking

March 12/2008 e-mail to Jeff Blend:

Jeff, another Life's Principle that relates to systems thinking is multi-functionality. I just posted something about Intelligent Bioplastic, a PLA plastic that has shape-memory properties and is also easily recyclable, in addition to be made from corn. Focusing on a single problem may result in a product or service that is not economically viable. By looking at the larger system and combining multiple 'goods', the value proposition can be dramatically improved. We talked about plug-in hybrids as potentially more valuable to utilities than the drivers in terms of adding low-cost buffers into the grid. A similar case could be made for solar air conditioning. At the moment, solar A/C is very expensive, and my electricity costs are pretty low (I do not think the energy savings will ever pay for the more expensive air conditioner that I bought last year). However, by reducing peak power demands, solar A/C could avoid the need for peaker power plants or expensive purchases of peak power from other utilities. It might be in the best interests of the utilities to subsidize solar A/C, assuming it is technically viable.

The challenge is identifying potential systems solutions. the OTSM-TRIZ 'system operator' model can be useful here as well as in the 'free energy' situation. What are the sub-system, system and super-system implications of a technology? Can thinking about the past, present and future give us ideas on how to get more value? Ideally, you also want to have a 'systems model' of the key problems facing us, so that you can combine 'pull' with 'push' idea generation.

Regards, Norbert