Plastic materials derived from natural renewable feedstocks can now compete, in terms of performance, with petrol derivatives and are becoming very popular within eco-responsible consumers.
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big debate is going on regarding whether or not this materials represent a real sustainable alternative to conventional synthetic plastics.
The main concern is that the majority of bio-monomers available on the market are obtained from edible crops in particular soybeans, potatoes, tapioca, mais: crops farming is often responsible of deforestation and requires the use of oil-fuelled machinery as well as large amounts of water and fertilizer for irrigation. Frequently, cultivation of these crops tends to be cost ineffective for farmers and must rely on government-subsidized sources of income.
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Cashew Nut Shell Oil, being a agricultural waste material, provides a compelling alternative as a source of monomers than other natural resources.
Anacardium tree grows in poor equatorial soils not well suited for other crops, it requires negligible irrigation and pesticide usage and, in addition, it does not deplete the soil, but it can help its rehabilitation.
The Cashew tree is a productive species that provides income for farmers in the equatorial region thus naturally discouraging the indiscriminate cutting down of trees. Harvesting of the cashews is very different than other crops, nuts are gathered by hands and this provides further income for the population of the region and limits environmental impact. The empty shells produced during kernel processing, contain approximately 30% by weight of CNSL and after extraction can be burned and used as fuel.