not all you can state straight hair , no wave.
but be aware thats what you'll get. and straight hair without any wave wont give you the freedom slight wave will. or the style flexibility.
nothing wrong with straight hair, everyones diffrent if thats what you want, enjoy it.
i'd avoid any straightening proccess on system hair, especially as you can order straight hair.
having seid that you could, but bear in mind it will dry out the hair and will be a constant proccess, once the hair as naturally growing curly hair straighened will return to its naturall state when subject to alot of moisture/damp/steam/excesseve sweat.
hapy wearing anthony