Question

why is Rayon not a synthetic fibre though it is human made​

Answer 1

Calling it synthetic fiber is also fine. Rayon is made from plant cellulose, but that cellulose has been rendered and reduced into it's basic chemical form. Rayon is a synthetically made fiber from those naturally occurring plant materials.

Answer 2

Rayon is not considered as synthetic fibre though it is human made because it is made up of natural polymer which is cellulose and not a synthesised polymer.

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