The smell of burning wool is like burning hair. Acetate burns readily with a flickering flame that cannot be easily extinguished. The burning cellulose drips and leaves a hard ash. The smell is similar to burning wood chips. Acrylic technically acrylonitrile is made from natural gas and petroleum.
Acrylics burn readily due to the fiber content and the lofty, air filled pockets.
A match or cigarette dropped on an acrylic blanket can ignite the fabric which will burn rapidly unless extinguished. The ash is hard. The smell is acrid or harsh. Nylon is a polyamide made from petroleum. Nylon melts and then burns rapidly if the flame remains on the melted fiber.