NCC-FOAM · Self-assembly of nano crystalline cellulose for lightweight cellular structures

Cellulose, the primary structural component of plants, is the most ubiquitous and abundant organic compound on the planet. When cellulose fibrils are processed under carefully controlled conditions, it is possible to release highly crystalline nano-particles known as “nano crystalline cellulose (NCC)”. Recently, NCC-FOAM partners have developed a unique technique for self-assembling NCC into highly ordered “puff-pastry-like” layered cellular structures, i.e. foams. This self-assembly process is controllable, and the final cell structure can be modified to produce open or closed cell geometries depending on the requirements of the end application. Furthermore, the constituent NCC nanofibres are sustainably sourced from paper mill or forestry waste.The controlled patterning of the nano-structure during the self-assembly process facilitates the infusion of resins for stiffening / strengthening and the production of foams with customised internal structures and directional strength. The inherent strength of the NCC skeleton means that only minimal quantities of reinforcing resin are needed, resulting in lightweight and cost-effective foams.Within NCC-FOAM, the overall objective is to develop an NCC foam/resin composite that enables the design, development and processing of sustainable structural foam materials. The use of infused resins has yet to be developed, the challenge being to produce foams that are simultaneously structural, durable and renewably-sourced. If successful, this would represent a true breakthrough for rigid foam technology. Furthermore, NCC-FOAM aims to bring the production techniques closer to industrialisation by developing the methods and equipment to produce foams with meaningful practical dimensions (at least 1 m x 0.5 m x 20 mm). Such samples will allow the feasibility of future industrialisation to be assessed, as well as permitting a full characterisation of the materials.