What product to keep my straight hair smooth?

well I am half white half black I have thick corse curly hair and I love it_ I also straighten it and it looks great either way this year for prom I wanted to wear it straight and I was wondering what product I could use so when it gets humid during the dace it wont curl up or get frizzy and big? Does anyone know of any good de frizers? I was thinking like black people oil I used to use would work but I don't know?

Hi,

I've looked at reviews for IsoPlus, and the leave-in conditioner has good reviews for keeping hair soft, manageable, and not frizzy.