Cellulose "nanopaper" as building blocks for sustainable materials

Increasing energy cost, heavy legislative pressures, consumer's demand for environmental friendlier products, carbon neutral technologies and a sustainable future have all triggered fresh interest in research and development of green(er) materials. In this context, cellulose nanofibres are regarded as the prime candidate for the production of high performance sustainable composites. However, the high tensile stiffness (up to 160 GPa) and strength (at least 1 GPa) of a single cellulose nanofibre has yet to be fully exploited in composite materials. Numerous researchers have already manufactured bacterial cellulose (BC)- or nanofibrillated cellulose (NFC)-reinforced polymer composites. Whilst these studies showed the ability of nanocellulose to improve the mechanical performance of polymer matrices, many of these nanocomposites still performed worse than or only equally well compared to PLA, which is one of the highest performing bio-derived polymers that is commercially available at a reasonable price.

This proposed project aims to develop the next generation of nanocellulose-reinforced polymers applying green engineering principles to reduce the use of solvents and energy, as well as introduce simple manufacturing concepts to produce sustainable nanocomposites that are truly high performance for high volume structural applications. To achieve this, this project will concentrate on the use of: (i) ultra-low grammage or (ii) high performance cellulose "nanopapers" as the building blocks for sustainable composite materials. It can be anticipated that such truly green and high performance nanofibre composites will find wider applications for instance in the composite, plastic electronics and flexible display industries.

The main beneficiaries of the proposed research will be the academic engineering science community and the UK/EU engineering, as well as industrial manufacturing base throughout the value chain, from materials suppliers to end users. The concepts explored in this proposed project are of fundamental interest to various industries including the composites and pulp and paper industries. A recent report by the Royal Society, "The Scientific Century" makes six recommendations around the long-term support and investment in science, including (i) put science and innovation at the heart for a strategy for long-term economic growth; (ii) prioritise investment in excellent people; (iii) strengthen government's use of science; (iv) reinforce the UK's position as a hub for global science and innovation; (v) better align science and innovation with global challenges, (vi) revitalise science and mathematics education. This project will focus on most, or if not all of these recommendations. As the manufacturing technology described in this project is as simple as making paper, it is cost-effective and easily scalable. This particular attribute appeals to UK's manufacturing industry, particularly the small and medium enterprises which do not have large amount of starting investment in manufacturing equipment. The know-how of nanopaper manufacturing and design procedures developed throughout the course of this project will be applicable to the area of materials engineering and technology, as well as fabrication of nanostructured materials. Whilst the current price for nanocellulose is still rather high, the successful outcome of this project will aid the commercialisation of nanocellulose products, where its relatively high cost can be justified by materials performance. Furthermore, this project will have major educational outcomes; it will provide research experience in novel manufacturing methods, materials testing and characterisation techniques, training in methodology and transferable skills for researchers working in complementary research areas. The successful funding of this project will train and educate the next generation of researchers in the area of composites manufacturing, in line with UK's composites strategy. Since this research is conducted in a university environment, the undergraduates will be exposed to materials driven research in a chemical engineering setting. The consumer and the wider society will also benefit as a whole, as the outcome of this project will include, for example, more environmentally friendlier materials through the use of greener starting materials, simpler manufacturing methods and reduced materials usage. The materials manufactured throughout this project will depend on the outcome but likely to provide an alternative to glass fibre-reinforced composites. Moreover, these materials also have the potential for reduced through-life cost, which the end users demand. To maximise the impact of the proposed project, the benefits of this research will be publicised to a much broader audience, capatilising on our societal needs for environmental friendly materials. Results will be disseminated at various international conferences and peer-reviewed publications. Where appropriate, commercially relevant materials will be protected by patent applications, which may be licensed or spun-out through UCL Business, the exploitation arm of UCL. A dedicated website will also be set up to further disseminate the outcome of this project to target the relatively narrow confines of academia. Here, UK and EU policy makers will have the chance to review, investigate and come up with new policies to drive the direction of sustainable composite materials.