Design Principles for New Soft Materials

Soft materials include colloids, polymers, emulsions, foams, surfactant solutions, powders, and liquid crystals. Domestic examples are (respectively) paint, engine oil, mayonnaise, shaving cream, shampoo, talcum powder and the slimy mess that appears when a bar of soap is left in contact with a water. High tech examples of each type are used in drug delivery, health foods, environmental cleanup, electronic displays, and in many other sectors of the economy. Soft materials also include the lubricant that stops our joints scraping together; blood; mucus, and the internal skeleton that controls the mechanics of individual cells.

The intention of this Programme is to use a combination of theoretical and experimental work, alongside large scale computer simulation, to establish scientific design principles that will allow the creation of a new generation of soft materials demanded by 21st Century technologies. This will require significant advances in our scientific understanding of the generic, as well as the specific, connections between how a material is made and what its final properties are. As soft materials become more complex and sophisticated, they will increasingly involve microstructured and composite architectures created from components that may be living, synthetic, or a combination of the two. The design principles we seek will ultimately allow scientists to start from a specification of the interactions between these components, and then create new materials by intentional design, rather than simply trying out various ideas and hoping that one of them works.

There could be great rewards from being able to do this. Even in long-established industries (such as the food industry, home cleaning, personal care products, paints etc.) products made of soft materials are continually being updated or replaced. This is often in order to make them healthier, safer, or more environmentally friendly to produce. Currently, however, the process of developing new soft materials, or improving existing ones, usually involves a large element of trial and error. A set of design principles, based on secure fundamental science, could speed up that process. This would reduce costs, increase competitiveness, and improve the well-being of consumers.

The benefits would be even greater in new and emerging industries such as renewable energy. Soft composite materials have many potential applications for use in high-energy low-weight batteries; low cost solar cells; hydrogen fuel cells; and possibly biofuels. However the design requirements for these applications are demanding, and often involve quite complex microstructures with specific functionality. The same applies in other emerging areas, such as industrial biotechnology and tissue engineering, where soft materials are used to create specific environments in which enzymes, cells or other live components can be used to perform particular tasks. As well as shortening lead-times and costs, by establishing the general principles needed to put new design ideas into practice, we hope to allow innovative soft-matter products to be created that otherwise might never come to market at all.

The research planned in this Programme addresses areas where improved scientific understanding can guide the design of new soft materials of high functionality. There is broad relevance not only to academic beneficiaries (as detailed separately above) but also to a range of industrial sectors such as food, personal care, functional ceramics, pharmaceuticals, environmental remediation, display technology, catalysis, energy storage, industrial biotechnology, agrochemicals, and renewable energy. Several of these sectors feature prominently in Research Council priority initiatives such as those in Manufacturing the Future, Energy, and Healthcare Technology.

The potential impact of successfully delivering this Programme is substantial. For example, in foods and personal care products it can take five or six years to develop a new product line. Even in these relatively mature technologies, evolving market demands, alongside changing environmental and health regulations can require product reformulation at relatively short notice. All too often, substitution of even a single ingredient with another of apparently similar properties causes the whole formulation to fail, with expensive consequences. These might be avoidable, if the formulation of soft matter products were more firmly grounded in scientifically secure design principles, of the type that we hope to establish with this Programme.

These avenues will be pursued with our Project Partners: four international companies with strong UK operations that directly involve the manufacture and processing of soft materials (Unilever, Mars Chocolate, Syngenta, Johnson Matthey).

Among emerging technologies, the potential gains are even greater. The ability to rationally design new soft materials could not only shorten lead times and costs but allow products to be created that otherwise might never come to market at all. Areas of the economy that could benefit include functional ceramics; (bio-)catalysis; environmental cleanup; and industrial biotechnology. In several of these sectors (as well as in pharmaceuticals and foods) there are exciting possibilities for creating new materials in which some of the components are biologically active (enzymes) or indeed alive (bacteria, tissues). Examples include cell scaffolds for tissue engineering; electrodes for microbial fuel cells; and food gels to deliver specific health benefits. Some such materials already exist, but most have been designed by trial and error.

Another large opportunity for impact is in energy materials (batteries, fuel cells, photovoltaics) where low cost, self-assembled structures for electrodes, light-harvesting photon collectors and other components are now urgently needed. Some of the most promising conceptual avenues towards the complex and specific microstructures required involve soft matter -- either directly, or as precursors or templates for the final product. A step change in our science-based capability to design and develop such materials is now needed, if the challenges of low-cost renewable energy storage and generation are to be met.