Plastic / Acetate Glasses
Plastic/Acetate Eyewear was made mostly for its durability and lightweight. Nylon is also a premier material for sports and performance frames that are very resistant to hot and cold and are more flexible, yet also stiff.
It may sound odd, but plastic made of castor oil (actually, castor seed oil) is now used in some eyewear. Reasons for castor oil plastic development include the high price of petroleum and the ease of growing castor bean plants.