The story of plastics actually began with cellulose, way back during the last two decades of nineteenth century. Cellulose, isolated from wood pulp was subjected to serious chemistry and Hyatt Manufacturing Company brought out celluloid in 1870. This was cellulose nitrate made sufficiently pliable by adding small amounts of camphor. But the material had a huge drawback; it was a fire hazard, it burst into flames spontaneously at the slightest provocation. In fact its more popular name was gun cotton and often substituted for gunpowder. Its meeker cousin cellulose acetate was synthesised by French chemist Paul Schutzenberger. The credit for taming cellulose acetate and unravelling several of its useful qualities goes to two siblings Camille and Henri Dreyfus. They found that cellulose acetate could be made into neat protective films, spun into fibres, and could also be injection moulded into any desired object. In 1912 Swiss chemist Brandenberger perfected the art of making cellophane a thin transparent film which revolutionised the packing industry. But the golden period of cellulose plastics was short lived. The two world wars demanded cheaper, more versatile plastics and the petrochemical industry generously provided cheap raw materials for the nylons, polythenes, polyesters, polyurethanes, polycarbonates etc..... Cellulose was marginalised for limited applications.
Cellulose chain courtesy Wikipedia
In a recent comprehensive review Tian Li and coworkers highlight the need to relook at cellulose. They build a case particularly for cellulose fibres downsized to smaller free standing fibrils. Such microsized or nanosized fibrils could be made into transparent papers with gloss and texture, excellent for various packaging applications. This biodegradable material could prove to be the best alternative to the millions of tons of nondegradable plastic garbage we keep accumulating on a daily basis. 
Courtesy :wikipedia
These fibrils could also be excellent reinforcing materials. Cellulose has an abundance of hydroxyl groups which can form extensive intra and inter chain hydrogen bonding. Such networks can improve the mechanical properties of composites. It has since been established that nano cellulosic fibrils perform far superior to conventional micro size fibrous reinforcements in composites. Japan's Ministry of Environments has already taken note of this and initiated Nano Cellulose Vehicle Project (NCV) to develop lightweight automotive components. Calculations show that a 10% reduction in the weight of the vehicle could reduce fuel need by about 6%.
Though cellulose is a plentiful, renewable resource, challenges remain. One that tops the list is the energy and cost intensive steps involved in the isolation of cellulose and its subsequent processing into nano form. Global teams are at work to tackle this challenge. Researchers at the Edinburgh Napier University in collaboration with South African Paper and Pulp Industry (Sappi) seem to have developed a cost effective process to turn wood pulp into "nanomaterial that could be used to build greener cars, thicken foods and even treat wounds".
REFERENCES:
1. "Developing fibrillated cellulose as a sustainable technological material. Li et al.; Nature 590,pp 47-56, 4 February 2021
2. Tokyo Motor Show 2019: NCV (Nano Cellulose Vehicle Project)
3. Conversion Economics of Forest Biomaterials: Risk and Financial Analysis of CNC Manufacturing
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